Nest Thermostat

Yeah, a thread about a thermostat.

Company web site: http://nest.com (I wonder how much they paid for the domain?)

News at Engadget: http://www.engadget.com/2011/10/25/ipod-fathers-unveil-their-next-project-the-nest-learning-thermo/

This is an "intelligent" WiFi thermostat. Unfortunately, my most pressing questions aren't answered in any of the previews or marketing materials... So I wrote them an email to ask.



With HRV I'd like to stop using a secondary controller and integrate into one unit - that would also give WiFi access to HRV which is thing that received the most manual adjustment.

Humidifier is currently controlled via its own controller mounted near the HVAC equipment in the basement. This type of controller needs to also know the temperature outside (via sensor) so it can add humidity to ambient without creating condensation on the windows (calculating dew point based on outside temperature)

Typical thermostats either have an ON/AUTO setting for the blower fan on forced air systems. The fan will come on during heating and cooling cycles and turn itself off when the cycle is done or isn't running. However, for higher efficiency in maintaining a balanced ambient temperature throughout the house, it's a good idea to keep the fan running at all times along with all your interior/room doors open. This keeps the whole house at a similar temperature and keeps air flowing. The issue is that the fan produces noise. Being able to schedule the fan during the off-cycle periods would be ideal. Some high end thermostats have this ability.

The main thing I want to know is where in the blue blazes they found a circular LCD, and why couldn't we find one when we were making the Vibez?

Peter

Wait...what?

Room doors. Sorry, I forgot to edit that earlier when I was cutting and pasting. The idea is to keep air moving around the house to keep the temperature as stabilized as possible, because some rooms will naturally be colder than others, given the construction of the house and location of the room.

(Interior doors)

Poked around a bit more on their site:






By playing around with the buttons on their compatibility checker I also learned they're "putting the final touches on" a Nest Thermostat+ which will, among other things, support multi-stage. Don't know anything else about it though.

It didn't exist until 2007?

Hmph, good answer!

Peter

What makes you so sure it's a circular LCD, and not just a square LCD with circular bezel over top of it?

The pictures in the link?

I must admit that learning over a 7 day period, sounds to me, like a completely stupid implementation. I suppose it's great for people that are slow (a few cards short of a full deck), but seriously, if they're this proud of their design skills they should have implemented something that could be set up in 5 minutes by anyone.

I love the design and I love the WiFi. But I don't make adjustments to my thermostat 1500 times per year like the cavemen they obviously surveyed for their stats. Pretty much I leave a set temperature for the winter and a different one for the summer. When we didn't have a baby/toddler in the house I had separate night time temperatures, but it's not feasible right now to drop the temperature too low at night with the little one constantly uncovering herself while asleep.

I see a bunch of other randomly useful things with this. Since it's got some kind of motion sensor in it, you could turn it into a makeshift security system.

Since I'm part of the apparently small minority of people who know how to program a thermostat, I don't expect it would save me a lot of money, but I'd probably still buy it for all the other neato features, like being able to pull our your phone when you're heading home early from work and have the air ready by the time you get home.

As to the 7-day learning thing, I'd probably never have the patience for that. I'd just pre-program it with the same schedule that I programmed into our current thermostat and then let it do its automatic adjustments from there.

How dare they try to cater to the majority of the market and start with a whole new approach! ;-)

I see a lot of possibilities with this. My schedule is not fixed, so a fixed schedule thermostat is not the most efficient for my needs. There are trends in my schedule, and if this thing is smart enough to figure them out, it's one less task I have to think about, while still gaining benefits. What would be really cool is to tie it into the iPhone geofencing abilities with iOS 5. Interconnected, the thermostat at home could know when I'm headed that direction outside the normal trends and ensure the house is at a comfortable level. Extremely useful for the painfully hot Austin summers, where I tended to shut down my AC system completely during the day.

I'm all for a new take on thermostats. It's funny, over the past month I've actually been looking for thermostats that work over Z-Wave or WiFi, but all the current products out there are pretty terrible, or they cost a good deal more than the Nest but with half the features and a quarter the style (not that the look of it is my biggest priority).

I really would prefer that it NOT have the learning capabilities. That's not very useful to me, since I work from home a lot of the time, and so I'm in and out of the house at completely different times from day to day. But being able to adjust the thermostat over WiFi would be great. I'm also interested in learning more about how each Nest talks to each other.

My home is VERY difficult to work with when it comes to temperature control (I've posted a thread about it here before). We have two floors, with a thermostat on the first floor, and duct work in-between the levels. This is an awful design. It means that there's almost no way to keep the top floor cool. In the summer, the AC cools until the first floor is cool, which means the top floor stays warm, even when I close all the vents on the first floor and open the ones on the second. In the winter, even though I flip the vents, because the ceilings are so high, it takes a while for the heat to reach the thermostat on the wall, and the top floor fills from the vents on the ground. Again, it's a terrible design. It's taken me four years to finally get things to the point where I've kind of figured it out. But there's still problems, and the second floor continues to be 3-4 degrees hotter than the first at almost all times.

What I'd love is a system that would know to trust a thermostat on the second floor when we went to bed, and the first floor the rest of the time. But at the very least, if I was having trouble sleeping because it was too hot on the second floor, it would be nice to use an app to turn the temp down without going downstairs (first world problems).

That would be pretty cool. Because as it stands, to "program" the remote automatically over the 7 day period, you have to go make manual adjustments to it multiple times per day. If you don't, forget, etc. then it's going to be set incorrectly. I suppose it will eventually correct itself, but how many week do you want to go and keep making manual adjustments?



Around these parts, that's standard, and it's exactly that way for some 99% of homes.

If you found other thermostats lacking, perhaps you didn't see the Honeywell Prestige 2.0 IAQ:

http://yourhome.honeywell.com/home/Produ...fort+System.htm

It requires a number of doo-dads, but once they're connected, you have WiFi, app control from phones, outside temp and humidity, inside humidity control, ventilation control, more advanced control of the blower fan as I want, and more. You can install additional sensors and it will average (by default) the temperatures from the different sampling locations. I suspect you should be able to override this to get it to respond to one specific sensor.

I'm pretty sure another one of the WiFi products, maybe that Bee one I can't remember the name for right now, had separate control and monitoring sensors. So you could move the sensor to sample ambient elsewhere, while keeping the control module where the wires are.

There's only so much a thermostat can do however to overcome a poorly designed HVAC system. In a bigger home you'd have multiple furnaces and air conditioning units to service different parts of the home, allowing better control of each zone.

Maybe up in your parts, but not in the homes I've lived in, and even if you're right, that doesn't mean it's a good design. IMO, it's the worst possible design for heating a home, particularly one with high ceilings, and at least as far as even temperature distribution goes.

The Wired article says:


Given that these are former Apple people, you know they've got apps on the brain. The big question is whether they just expose an API or whether they try to create an "ecosystem" that they control. It's easy to see a variety of sophisticated uses.

My guess is that somebody like Honeywell offers them a scandalously large amount of money and they promptly get sucked in.

One more factoid: Nest originally set themselves up to sell direct to the consumer or via BestBuy. The demand apparently crushed their web site this morning, and now store.nest.com redirects to bestbuy.com.

Matt, I didn't say it was ideal. In terms of design, there are a lot of fine points in the implementation and it's possible that with two different installations, in one home it works well and in another it doesn't, even if both homes feature the same floor plan and ceilings.

Just in case I misunderstood, the "typical" system I'm describing here has the furnace and AC coil ("the furnace") is in the basement and the AC evaporator somewhere outside. With basement ducts and 1st floor ducts in the basement ceiling. Then second floor ducts in the 1st floor ceiling. That means heat/cool come to the first and second floors via vents in each respective floor. This is what I understood that you were describing about your own system.

There's a lot more to efficiency and performance than just throwing a furnace and some duct work into a house.

Many, but not all, the homes in my current sub-division have employed a twist on this standard design. These are homes that were built in a factory and transported in one piece to the foundation. Theyre also designed to be Energy Star compliant. For the top floor, a central wide duct comes up from the basement all the way to the attic. Branch ducts then go to each room and vent in through the ceiling. All the ductwork in the attic is incased in 1.5 feet of expanded polyurethane spray foam (it's solid, you can walk on the stuff).

It's working reasonably well, though I am careful about which vents to leave open and which to close to move air around and create a stable/even temperature. The top floor doesn't vary from the first by more than 1-1.5 degrees. The exception is one room on the top floor that has a large bay window, in which the temps can rise significantly because of all the sun that enters. Plantation shutters takes care of that fairly well, along with keeping the fan on to move air around throughout the house.

Having some type of automated baffle system that could control airflow to individual parts of the house would be pretty cool, but I've never heard of such a thing being installed in a residence. That would be a neat way to direct airflow without requiring multiple furnaces or AC units.

Not surprising considering the amount of coverage they're getting. The clever circular LCD and jog shuttle approach are attention grabbers.

It'll be interesting to see what kind of reply I get to my email query from this AM.

There are inflatable bladder systems that you can retrofit in residential systems fairly easily. It involves running pneumatic tubing inside the ductwork from the ducts to a central point where they are attached to a computer controlled manifold. At the duct end, the tubing is attached to inflatable bladders that are secured near the end of the duct with a framework. The manifold can then inflate the bladders to block airflow to that duct. The tubes are run with the use of a big fan, blocking all the ducts but the one you're dealing with, a long piece of string, and a small "parachute".

Damn, sounds like a fine idea. Any links?

http://www.homecomfortzones.com/products/works.php

The pictures don't show a dismantled view.

The way I see it, the top is domed, so unless the LCD is also curved to fit that dome radius, it can't sit flush with the top of the thermostat. If it's offset, then the LCD can be larger than the actual area of the circular visible display. If it's larger, then the LCD itself could easily be square, with circular masking, no?

It looks to me like the LCD is circular and that the fascia around the LCD is beveled. This bevel would preclude or make it very difficult to use a non-circular LCD. This wouldn't be the first product using a circular LCD.

Bitt, that looks amazing, thanks for the link - saving it for future reference. They estimate pricing at between $3 and $5 per sqft of the home. Kind of pricy for a retrofit, so I wonder if that's estimated to include installation.

It is square, with a round bezel. Real round ones exist, but they cost.

Disclosure: I worked on that product too

I imagine it does, since they don't seem to sell to the consumer. I don't know why they would price it that way, though. Seems like there should be a pretty set parts cost.

I almost added to my previous post "That's the way I'd do it, because it's certainly cheaper than a round LCD, improving my profit margin."

Maybe if I used one it would end up being great but I agree with Bruno that having it learn my patterns would be silly. I just would want programmable so I can set the temps change whenever I want and have it store a winter set and a summer set. After I get the program setup I don't really change it.

I think it's funny to see coverage of a thermostat on tech websites

You mean you worked on the Nest thermostat? Do tell!

What I was saying about my system is that there is duct work only in-between our floors. So if you're on the first floor, the ducts are in the ceiling. If you're on the second floor, the ducts are in the floor. That's what I meant was a dumb design, and unlike other places I've lived.

Ah! Gotcha. That's exactly backwards from what I have. What I described is what I meant is used in most homes around here, and I suspect a great many in the US as well. At least in places that use forced air.

Yes.

My house in Alaska was very efficiently heated (we didn't concern ourselves too much with cooling. ) My heating bills were dramatically less than other people with similar sized homes -- sometimes by a factor of ten or more. I knew people whose heating bills in the coldest part of winter might run them as much as two or three thousand dollars in a single month.

My system was hot water baseboard with two "special" aspects. First, the boiler was a German unit made by Buderas. Buderas is unique in that they vary the boiler temperature depending on outside temperature, so instead of keeping my boiler at 190 degrees (F) all the time, it might run at 110 degrees if the outside temperature was, say, 40 degrees. Buderas claims, and I have no reason to doubt them, that they will put the same number of BTUs into a home as a conventional system, but at 75% of the fuel consumption.

The second thing that made my heating system efficient is that I had seven separate and distinct heating zones, controlled by seven thermostats. All of my interior walls were insulated, so rooms I wasn't using (big house, I was there by myself) I kept at about 40 degrees in the winter time. Of course all the outside walls were 6", heavily insulated, all the windows were triple pane glass. Entry was through the garage which was semi-heated by whatever heat leaked through the wall to the living/dining room. At 40 below zero outside temperature, the garage would drop down to about zero degrees, which is no problem with a properly prepared Alaskan car.

All in all, I had a pretty efficient house.

tanstaafl.

You don't mention it specifically, but given the number of zones and my limited knowledge about what I see in that photo, am I correct in guessing you had radiant heating? One day I would LOVE to have radiant heating. THAT'S an efficient way to heat a house. You can heat the rooms you want, the heat stays nice and low where the people are, and in the winter you walk on nice warm floors.


Indeed, that's why my system is so f'ed up. We have ~9'-10' ceilings. If all my registers are open in the winter, it means that the first floor is being heated from the top-down, which is stupid because the heat takes forever to fall to where the people (and the thermostat) are, and it's primarily the top of the room that's getting the heat, which is very inefficient. Meanwhile, the top floor is being continually heated from the proper direction, but it keeps heating far past the point it needs to because the first floor hasn't warmed up enough.

Sorry, I really hate our system...

So, yeah, radiant heat.
Not "in floor", but radiant nonetheless.

Oops, missed that...

Yeah, you're right. The picture in the engadget link shows a round device in the guy's hand, which threw me. Looking more closely, the bezel leaves plenty of room for a square device inside, though...

Still looks really nice, though.

So will this work in the UK ???

Living on my own as I do at the moment, and being a man, I don't tend to touch the thermostat. But with a chance of circumstance just around the corner I like the idea of keeping costs as low as possible.

Cheers

Cris

We paid a lot of attention to our choice of heating system when we built our house. We ended up choosing a Geothermal heat pump system. (which is effectively the same technology you'll find in a refrigerator, but then reversed) This effectively means three holes of 100 meters deep were drilled in our garden, in each of which four tubes were put. (vertical ground loops) The tubes were connected to each other prior of being put inside the ground, effectively making for a 400 meters long circuit inside the ground. Then the three circuits were connected to each other, resulting in a circuit of 1200 meters. After the tubes were put into the ground, a cement compound was injected into the drilled holes, so nothing would ever touch the tubes.

In-house, floor heating was put everywhere throughout the house. Then, the tubes were filled with water, with a bit of glycol added to it.
The system is as simple as it is brilliant. Water flows through the underground conducts, effectively reaching the temperature of the earth at that specific depth, which is always about 6 to 10 °C (40 - 50 °F). That water then gets compressed by the heat pump, which effectively raises the temperature of the water. One circuit is heated up to about 30 - 35 °C (85 - 95°F) and flows through the heating tubes under the floors. This is more than enough to heat up the whole house to a nice comfortable temperature of 20 - 24 °C (70 - 80°F), or more if necessary (like in the bathroom). The other circuit is heated up to 55 °C (130 °F) and is stored in a 180 litre boiler for hot tap water. I had my doubts in the beginning that 55 degrees would be enough, but it turned out to be MORE than adequate, to bathe, to do the dishes, anything you need it for really.

Of course, this system works best when the house is insulated VERY good, which is what we did: 10 cm (about 4 inches) of the most efficient polyurethane insulation, which works very good. (in total, our walls are about 40 cm thick - all brick).

This system has a high startup costs because of all the materials that are needed (LOTS of tubes!), and the drilling of the holes also doesn't come cheap. But after that, you get a system which is very efficient. The heating pump works electrical, so obviously my electrical bill goes up. BUT... I do not use gas, diesel, wood or any other of the classical combustible fuels. That's why our house also does not have a chimney. Absolutely NO risk of CO intoxication or fire hazard, since no fire is involved in producing this heat. (our fire/home insurance loves this, and this is reflected greatly in our annual bill!) My monthly electrical bill is about the same as what my neighbour pays... but mine includes my heating and hot tap water production: his does not. The system is also maintenance free for its entire life cycle. (which is about 25 years)
Another big benefit: in the summer, the system can be reversed and the floor heating can actually be used to cool the house, at a fraction of the cost of what air-conditioning would cost me. (since the water is cooled via the earth) This works VERY well and I would want to be without it any more. Last summer, when the outside temperature was about 30-35 (85-95) degrees for weeks, this system had no trouble of keeping our house at a steady 20 - 21 degrees (68 - 70 °F)... at only the cost of a circulation pump of a few watts that needed to run.

This system is essentially capable of keeping our house at a more or less constant temperature of 21 degrees all year long, at about half the price of what gas or diesel would have cost me. I never need to worry about setting the thermostat or turning the heat off when I leave the house: the system is always running because it would consume more energy when I would turn it on/off all the time then to simply let it run at a constant temperature (again, the refrigerator analogy). Since the heat is radiant floor heating, it's a very pleasant and comfortable heat as well.

You can see some pics here of the holes getting drilled and the setup. This is not our house, but these people worked with the same firm as we did, so the used method is identical (in fact, the workers on the photos are the same who did the drilling at our place .

We simply LOVE this system and are very happy we ended up choosing it. It also takes a lot of the stress off because once it's paid for, there's no need to fear the 'dreaded monthly heating bill' any more.

So I'm not the only person in the world whose partner believes a thermostat is an on off switch then ?

"I've turned it to 25, so that the house warms up quicker"

I have finally managed to convince Eryl that the oven temperature dial isn't a switch, but convincing her that the same applies to the heat thermostat is a work in progress

Its not going to work in the UK out of the box as it is designed for 24V AC North American HVAC systems.

It seems to be able to control from Single Stage Heating up to 2-Stage Heating, Cooling and Ventilation.

I have put together a reasonably simple 24V AC Transformer and Relay fitted in a small enclosure which should allow the Nest to control common heating systems in the UK (and will hopefully offer more relays for people who have air conditioning systems and home ventilation / heat recovery systems). I hope to be offering these through my company pre-wired, labelled and with full instructions for getting it working here - just waiting on my pre-ordered Nest to arrive and make sure I get it working as expected and have everything in place to offer it here as a kit. There are still some details to work out (have contacted Nest yesterday, hopefully speak to them again today), but watch this space.

Reminds me of this sequence from Brazil

I use it as an on-off switch: turn it below 15 for the summer so we don't use it from April to September then back up to 18 or 19 for the winter.

Simples. And we just have one thermostat, in the main hall, but at least I do have a timer so it comes on in the morning and evening for hot water for the showers.

Somtimes I'm quite glad we don't need to think about aircon in this country :-)

That one sounds like a great dumb line, but in fact is true. The house does warm up more quickly on a higher temperature setting than on a lower one, at least with forced air systems.

The reason is thermal mass. At a 20C setting, the furnace heats up the air to 20-21C, then turns off. The air quickly chills back to 17C as the cold walls/floors absorb the heat, and then the furnace comes back on again 5-10 minutes later to repeat the cycle.

Setting it to 25C gives a single long blast of warmth, enough to get the walls/contents of the house closer to 20C in one go, after which one sets the thermostat back down to 20C.

Cheers

That might apply to forced air systems, it certainly doesn't to any radiator based system I've ever used.

I've never come across a forced air system in the UK, radiators are what you get in 99% (made up statistic) of UK homes.

Yeah, especially with older cast iron radiators. Good system, that was.

The homes in Canada are made out of kindling and papier-mâché, everything is hollow, so it's easy to install forced air systems.

And they were mostly built after modern heating systems were invented

It's kinda more efficient to keep the house at the same temperature all the time in order to avoid that situation.

Not so.

The only reason you put heat in a house at all is to replace the heat that has been lost through radiation, either into the ground or into the air surrounding the house.

The amount of heat lost through radiation is proportional to the fourth power of the difference in temperature (in degrees Kelvin) between the radiating body and the outside source that is absorbing the heat. Lessening this difference greatly reduces the amount of heat loss.

It is more efficient to minimize this difference whenever practical by allowing the house be cool (or in my Alaskan example, downright cold) when not in use.

tanstaafl.

If you don't mind my asking, what did your system cost?

Also, what are the climate conditions where you live, how cold in the winter, how warm in the summer?

My system was very expensive to install, but most of the expense was labor since it was replacing impossibly costly to operate electric baseboard heat, which meant that they had to knock holes through walls and floors/ceilings, and install many hundreds of feet of copper pipe, make more holes to run the wiring for the thermostats, etc. All of this in a 20-year-old house while people were living in it. Ugly... And that Buderas furnace wasn't cheap, either. But there really was no option. Had I continued with electric resistance heating, the house would have been literally unsalable. I saw the real estate crisis coming and knew I had to get out before the crash, and in Alaska nobody would even look at an electrically heated house.

My installation, parts, labor, and repair of demolition required for running the pipes came to about $23,000.

tanstaafl.

Err, no, it isn't. Major fuel/cost savings from turning the heat way down during nights.

Cheers

Most heat loss into the air, and all heat loss into the ground (unless the ground near you is transparent to far IR, which it isn't) is through convection or conduction respectively -- not radiation. Energy flow through both convection and conduction goes linearly with the temperature difference, not to the fourth power. But even so, I think your actual point still stands...

Peter

About 38.000 euro, of which 12.000 euro for the drilling alone. But the government was kind enough to subsidize about 9000 euro of the total, so it cost me about 29.000 euro. This could have been 3000 euro less even if I had been smart enough to have a heat-loss calculation done beforehand. As it is now, our heat pump is a 12Kw model. I'm pretty sure though that, because of the good insulation we had installed, a 6Kw model would have been sufficient. This 6Kw model is 3000 euro cheaper.
Also. This system is heating about 320 square meters of space.

Summers have temperatures of up 35 to 40 degrees - 95 to 105°F (40 being rather exceptional), winters go from minus 10 to minus 15 - 15 to 5 °F (again, 15 being rather exceptional). The humudity is also pretty high here, making the heat in the summer pretty unbearable.

I don't know how long it's been since you had that 'upgrade' done, but I can tell you take the cost of parts has gone up tremendously since the year 2000. Most things have doubled in price, sometimes even tripled. Same with the labour costs. Some of those workers are not ashamed to charge you 50 euro/hour ex. VAT! At those prices, if they show up with two, work 8 hours and have two days of work, they easily charge you MORE than most people make in a MONTH! In labour alone! I don't think this is very reasonable anymore, but what can you do? I do know that people won't be able to cope with these ever increasing prices much longer. At the rate this goes, my kids will not be able to build their own house any more (unless they do everything themselves).

And Buderus is really a high quality brand. They make heat pumps as well, but we decided to go with Nibe instead, since heat pus are Nibe's core market.

There are several things wrong with your assessment. First, far more heat is lost through conduction than radiation: the outside air touching your house, especially your windows. Second, you fail to take into account the energy required to reheat the walls, which have far more mass than the air in the house. If you're reheating the walls every afternoon when you get back from work, rather than minimizing the temperature difference between the walls and the (interior) air.

I'll admit that these calculations may be very different in significantly colder climates.

I agee with Bitt: if your house is well insulated, and you are using a radiant heat solution, then it will definitively be cheaper to just set it at a constant temperature and forget it than to switch it on and off all the time. The energy needed to re-heat the cooled off mass of the house is enormous.

This of course does not apply if you have a non-brick, badly insulated and heated by forced air systems/radiators house.

I don't think the actual temperature difference matters. Look at it from a conservation of energy viewpoint: the total heat lost from the house to its environment (by conduction and convection) must equal the total heat produced by the heating system, as (effectively) none of it goes anywhere else.

And if you keep your house heated the whole time, the steady state is when the inside surface of your walls is at room temperature all the time. This means that the temperature difference measured across your walls is always as high as possible (for it to be any higher, the inside surface would have to be above room temperature, which never happens).

But the heat flow (heat loss) is proportional to the temperature difference across the wall. So heat flow, under this plan, is always at maximum, 24 hours a day. Which means that any other plan -- even letting the house cool down for only an hour before turning the heat back on -- causes less heat flow into the environment, and thus less heat production by the heating system, and thus lower bills.

The energy needed to reheat the walls, while no doubt a lot, is not as much as the energy needed to keep them permanently warm.

Peter

Let me re-state it more simply.

No matter if you lose heat through conduction or radiation or just leaving your windows open, your heating system must replace whatever heat you lose. The amount of heat you lose depends entirely on the difference in temperature between your house (the heat source) and the outside (the heat sink). Think about it. If you were keeping your house at 70 degrees, and it was 70 degrees outside, you would lose no heat at all. It is temperature differential and nothing else that determines heat loss.

You are correct that the walls have more thermal mass, but that is irrelevant. All that matters is how much heat is lost to the outside. The warmer the air inside, the more heat that will radiate be conducted outside and have to be replaced. [Yes, you and Peter are quite correct about the conduction vs radiation issue. For whatever reason I didn't think about the outside air actually touching the house. )

It is astonishing (and rather appalling) to put this question to Google and see the amount of misinformation out there being propagated as fact. Even a slight knowledge of thermodynamics (all that I have) proves that any opportunity to lower your in-house temperature saves heating cost.

tanstaafl.

If you were heating your house with room temperature air, I totally agree. But I think because you're heating air to well above the target temperature, you're losing a lot of efficiency.

Argh. I'd really like to do some math and figure this out, but I just don't have the time right now. Things that may need to be taken into account are the amount of energy it takes to heat air vs. walls and temperature differences between outside, inside, and heated air.

Losing efficiency where? As long as the efficiency of your heater itself doesn't vary, in terms of what fraction of the calorific value of the fuel is emitted into the living space (in air of whatever temperature), the conservation argument remains the same.

Peter

Sorry, but I don't buy this. If this were true, it would be no use at all to insulate your house. How do you explain then that, back in the days when people did not insulate their houses, they easily needed a 35 to 40 Kw furnace to warm their houses to a comfortable temperature? If they now insulate that same house properly, they could easily do with a furnace of about 10 to 12 Kw (or even less) to also warm up that same house to the same temperature. The more powerful heater obviously also consumes a lot more fuel (not sure if its also about four times as much, but in any case a lot more)

And what about passive houses, which don't even have a central heating system anymore, but simply a LOT of insulation in the walls of their houses?

I know for a fact that, due to the thick amount of insulation in the walls of my house, my heating system doesn't have to work very hard to keep the temperature on the same level. It only switches on maybe once every two hours, and even then only for a few minutes. If I turn it off, letting the whole house cool down (which, granted, could take a few days), the system would be running for at least a day, none stop, to get the temperature back to the comfort level it was before. It would certainly consume more power during that 24 hr heating up period than it would have if I would just would have let it run constantly, only switching on a few minutes every two hours, with a total of maybe two hours per day.

Doug is correct. Insulation, due to its low thermal conductivity, only reduces the rate of heat transfer. It does not prevent heat transfer. You will eventually reach equilibrium with the ambient outside temperature, if you're not actively heating/cooling, and the ambient outside temperature remains constant.

The house will absorb some energy from sunlight, especially through windows, so it may be possible that the inside will never be quite the same temperature as the outside.

It can very easily be a lot hotter inside than outside, especially in the summer. Something pretty obvious. But nonetheless an mildly expensive lesson learned back in the summer of 2007 when I "boiled" the contents of a planted and stocked aquarium when I left the house for a few days and forgot to turn the AC on. Ugh.

I think insulation works both ways, it will also keep heat out.

I guess that is why my house is cooler than outside during the summer ???

Cheers

Cris

Right. I wasn't considering that, as I didn't really consider that as the outside environs remaining constant. I was thinking more in the same terms as physics' legendary "perfectly frictionless surface."

Yep. This is why my family's cabin is colder inside in the winter time then outside. It's a tradition to head up there, nominate some poor soul to run in, start the fire place, then run back outside while the rest are hauling supplies.

Right, what determines heat loss is temperature differential and quality of insulation ("thermal resistance") and total exterior wall area. But when evaluating different thermostat/timer regimens for the same house, the latter two of course remain constant, so only the first needs to be considered.

Peter

OK, one more time.

The only reason you run your furnace is to replace the heat that is lost to the outside. The greater the temperature difference inside to outside, the more heat you lose. It doesn't matter if it's the inside air temperature, the wall temperature, or what you're cooking in the oven. Temperature differential determines how much heat you lose.

You can try and make it more complicated by bringing in factors like insulation and glass area, but they only affect the amount of heat saved or lost at a given temperature differential. Their efficiency factor is fixed. It's temperature differential that rules.

tanstaafl.

No, Doug is spot on there -- the discussion is about whether to turn the thermostat down at night or not, and the answer (in cold climes like ours at least) is an emphatic "YES!".

But you are also correct -- better insulation always helps, whether one turns down the thermostat or leaves it constant.

The best conservation solution is of course to do both: insulate better, stop air leaks, AND turn down the thermostat at night.

Our heating bill would easily increase by 50% if we didn't turn the home temperature down by 6 degrees (C) at night.

Cheers

That's actually not where I was coming from. I doubt that 8 hours of a few degrees cooler is going to have a significant effect on the heat of the walls, certainly not enough to cause the kind of cycling you referred to earlier. I was thinking more of turning the temperature down 20 degrees or more while away for a weekend.

You don't want to see what happens (to a house) when you forget to turn on the heat here. It happened just up the street and looked somewhat like Mr. Freeze had just started making an ice castle. Pipes burst, walls froze, place needed to be gutted.

Oh, but I'm not arguing that. That I agree on, that, eventually the inside and outside temperature will reach equilibrium. My only point is that, because of the use of insulation and it's low thermal conductivity, you can slow down this process in such a way that it's not economical anymore to turn the heater down at night. (because in the morning it would have to do a lot more effort to reach the same temperature level as it was the day before and thus consuming more energy).

If you're leaving the house for more than a couple of days, then I agree you'd better turn down the thermostat to save energy and thus cost. But not in the course of 24 hrs, thanks to the insulation. I actually tried this last night now, just because I was curious. I switched off the heater when I went to bed, and when I got up 8 hrs later I looked how much the room temperature had dropped: half a degree. Ok, so this is not yet the coolest period of the year, this night it was 5°C outside. But I don't think the dropping of the inside temperature will increase immensely if the outside temperature would start dropping below zero.

A lot of the newer central heating installation don't even have thermostats anymore. They have what's called a WAR module on the outside and one temperature sensor on the inside. The WAR determines the heat of the water in the furnace. eg. At 10° outside, the water temp is 30°C, at 0°C outside, the water temperature is 35°C. The temperature sensor on the inside then determines when the circulation pump starts running and the heating begins or stops.

There's one thing I haven't brought into the equation yet: water temperature. With the older systems, which are used to quickly heat up rooms with the use of radiators, the water temperature is usually 60°C or more. Then when the thermostat is switched on, the water quickly needs to be heated to that temperature and kept constant until the correct temperature is reached. This consumes a lot of energy.

In my house, what is called a "low-energy-house" (=term that is used by the government), the water in the tubes is only heated up to 30 - 35 degrees, but then kept constant, in other words, the system is never turned off. At the end of the year, my system will have consumed less energy than the first mentioned, and that is why our government is now pushing new home builders to invest that extra euro to reach the "low energy house" standard. Because it IS more expensive: you need to insulate a whole lot more and make sure the house is air tight - because of this you now also need a ventilation system, which was not needed up to 5 years ago - but all those costs can be recuperated in an X amount of years (in my case: 7 years), and since the heat pump is claimed to last 25 years, the rest is pure profit.

Why am I saying all this? Because I want to make my point that it is not necessarily more expensive to let the heating system run at the same temperature all the time instead of turning it off/off every day, providing you did the homework and insulated the house, made sure it's as air tight as possible and use a heater of less Kw which uses low water temperature and an over dimensioned radiator as a heat release system. (like eg. floor heating tubes are because essentially the whole floor is a radiator then). Then, and only then will the bill at the end be less, and significantly less than a normal house with an old school heating system (trust me: I know because I live in such a house and it's me who pays the bills )

I'm not saying you can stop heat transfer/thermal conductivity, that was never my intention to claim and if it came across like that then I apologise. I know you can't do that, it's a law of physics and as Scotty always said: "you cannae change the laws of physics!" But you can bend them a bit to your advantage, by using modern techniques.

And mine is that, even though good insulation and good system design can reduce the cost of running the heater overnight to arbitrarily small values, the physics of the situation means that the cost if you turn it down is always fractionally lower still.

Peter

Let's agree to disagree then. I can only tell you that my heating cost is now considerably lower than it was before. That the government even subsidises people who are willing to invest into converting their houses into "low energy houses". Why would they do that if it was useless and would even consume more?

And most of all, I know of several people who have actually done the effort of keeping record of the expenses when then did the on/off method, then did the home upgrade, changed to low-energy and constant temperature and again kept record or their monthly costs. Even though the cost of energy had gone up since the year before (as it always does every year) they noticed a considerable lower monthly cost than before. Are all those people lying then? I don't believe this, because I've noticed the same thing myself.

The government did not pass the Law of Conservation of Energy and is not in a position to repeal it

All I'm saying is, if upgrading your insulation, eliminating draughts, installing a heat-pump, and leaving your heating on all the time produces a "low energy house" -- then upgrading your insulation, eliminating draughts, installing a heat-pump, and not leaving your heating on all the time will produce an even lower-energy house.

The only way it might be otherwise, is if the heating system itself is more efficient at low outputs than high outputs. This is, to a certain extent, the case with heat-pump systems (it certainly isn't with conventional fossil-fuel or electric heating), but even so, if the reheating after a cool-down is gradual enough, it still seems likely to be a win.

Peter

Of course it is. More efficient system, better insulation, etc. But your present system would consume even less energy than it does now if you took steps to minimize the temperature differential inside to outside. Maybe not a LOT less, with a hyper-efficient house like yours, but less.

Yes, your system "works harder" for a little while to bring a cold house back up to normal temperature than it does while maintaining a constant temperature. But all it is doing is replacing the heat lost during the period when it was "working less hard" because of the reduced temperature differential. Lower differential = less heat lost = less heat to replace.

As you [Scotty] said, "You cannae change the laws of physics."

tanstaafl.

I'm about to do some major renovations to my house - adding a second floor of about 900 sf - so this discussion is very timely!

Thermodynamics was a very long time ago, but I have to agree with the folks who say turning down the thermostat at night saves power (on most systems). Especially on cold winter nights when the delta is greater. (One system that probably wouldn't see savings is a heat pump with an auxiliary heating element when the element kicks in - it's way less efficient than the heat pump alone.)

I currently have a typical hvac setup for my neighborhood: forced air with a natural gas furnace and elec AC; gas also heats our water. My current (web enabled) programmable thermostat is set in winter to heat the house to 68 at wakeup, drop back during the day, up again in late afternoon and evening, and down to 60 at night. Our house is older, and loses heat all too quickly in the winter, even in the not-too-terrible climate of greater DC. It's hard to compare winters or factor the water out, but our gas usage did go down after adding the programmable thermostat about four years ago.

We're investigating geothermal as part of our renovation. The startup costs are high, but there are some nice tax credits and we intend to be here at least 15 more years. And I hate the noise of my AC's compressor in the summer!

-jk

This is starting to remind me of that airplane on a treadmill thread...

I think the place you've been mislead may have been from the marketing fluff for your hyper-efficient heat-pump. Those systems have one small flaw, in that they can take a very long time to warm up a house (compared with other methods). So I imagine the salesfolks might feed lines like "no need to turn down the thermostat".

Even with that slight "flaw", ground source heat pumps are probably the very best way to go, when circumstances permit.

Where we live here, people with systems like yours need a back-up heat source for REALLY COLD times. A few days a year, nothing more.

Cheers

This could be. Floor heating is indeed a 'slow system' when it comes to heating up a house. On the other hand, I find the whole 'not having to worry about the thermostat' thing very comforting.

It's not that I don't want to believe you, but I'll certainly look further into it, this is interesting stuff.

I would be interested in more data on that thermostat. Last time I looked into it, most were of questionable calibre.

I wonder what is available now (for North American FAG heating system).

It's nothing fancy - a Venstar thermostat on an Insteon home automation rig. It works adequately.

-jk

EcoBee which has been brought up before, seems to offer control of more HVAC options, including multi-stage heating and cooling, HRV and central Humidifiers and Dehumidifiers.

I was actually thinking about this earlier. Dealing with a forced air system myself, I wonder if the nest (or another thermostat) could learn to adjust for this effect in a forced air system. Since starting and stopping the heating elements and fan over and over takes energy and is also annoying, it seems like it might be worth doing. Caveat: I'm not really familiar with the space, so there may be more standard products out there that already do this...

If you're doing a 2-wire system (ie just 2 wires going to your transformer and relay), you need to be careful as to the relay you use as nest trickles current through the relay coil, without closing the relay, to charge the internal battery.

If you're supplying a setup to anyone, the best idea is to ensure you have a common wire (ie, both sides of the transformer come out to the thermostat end, as well as the one wire that goes through the relay back to the transformer) - ie run at least 3 wires vs just 2. This is far by the better solution if you have the choice.

Let me know my PM if you want any more specific advice

Yes. Obviously they have a penchant for secrecy (which has worked quite well, given the amount of publicity they got mostly for free), so I can't tell you details but I did the initial designs, devboards, bringup, etc.

Good to see that it's bought some attention to an unloved area of the home!

Any hope that Nest will build a third-party hacker-friendly ecosystem around itself?

I guess that's a wait-and-see...

How long until it gets it's own App store...?

After thinking about it for a bit, I'm sold. Signed up to be notified when I can buy one, looks like the response was way higher then expected.

The trigger has been the highly erratic rain weather over the past few days. The change has caused my system to need to switch from the occasional AC usage, to the occasional heater usage. Current free thermostat from the apartments sucks, with no way to have both a heat and cold schedule. It's one or the other, and my heat schedule was so messed up, it was trying to heat the apartment up to 76 when it ticked over to 10am.

Our Honeywell thermostats (which appear to be an older variant on this design) have an "auto" mode where they will do both heating and cooling, based on the schedule you programmed in. Not that I had any idea for the first two years we lived here until somebody told me about it and I had to dig up the user manual online.

So... if all you want is a hard-to-program thermostat that can deal with a/c and heat automatically, you only need to spend $38 on this Honeywell.

(N.B.: if you really and truly want this feature, make sure you root through the whole Honeywell line to make sure the one you get actually does have this feature. The link above may or may not actually have it...)

Yep, that would be a far cheaper way to avoid one annoyance, but enough of the Nest concept appeals to me that I still want to get one. Things like the WiFi connection allowing remote control is a first step I can take towards home automation.

I figure the initial investment will be worth it long term. If I move, I can just take it with me. And by buying in now, I can help vote with my wallet that this concept is what I want to see more of. I'm really adopting the idea lately that technology hasn't done a great job of serving us humans like it should. Any concept that blends high tech with ease of use and making the tech disappear is something I want to support. I also don't want to be tech support for my friends and family, I want their tech to just work for them. Depending on how well the Nest works out for me, it may also turn into christmas presents for people like my grandparents. One little piece of tech to help them save money on their heating and cooling needs, and in turn assisting them to stretch their retirement dollars out.

Plus, this helps keep people like Hugo employed, leading to fun and new toys for us tech geeks to lust over

...also very much the reason I tend to support stuff I think is promising. eg, we have a Prius even though we don't drive enough to make it at all financially beneficial; the chances are one of the subsequent owners *will*, and it's a vote of support towards the people developing these things.

If everyone just said "meh" towards the early versions of products because they weren't quite "there" yet, there wouldn't be followups...

I do hope I can count on your support for my current project

Just let us know more - hint hint :-)

I was just looking at this — I've been meaning to get one of these for ages — and it turns out that despite the fact that the Honeywell web site claims that the RTH6350D model has this feature ("Auto change from heat to cool"), it does not.

Maybe you want the RTH6450D? Still pretty cheap on Amazon. (FYI, this appears to be pretty much the same as what we've got, but with a different plastic bezel.)

Yeah, it is. I was just pointing out that the documentation on their web site is wrong. (Apparently the 6350 and 6450 share a manual and the autoswitch exists only on the 6450.)

Amusement: I count 52 different thermostats on Honeywell's web site. I suspect they could pare things down quite a bit from that.

Yeah, that was one of the first impressions I had of their site, too. It seems like they thought "we need to have thermostats at every price level between $20-400, in $5-10 increments."

My fear is that Nest will gain some modest amount of success and will promptly be purchased by Honeywell, being thus folded into the above lineup and made to offer ten versions at slightly different price points.

Amusement: I ordered my Nest gear via BestBuy.com because Nest's own web site had melted down shortly after they went live. I just got the following email:



Needless to say, I'm confident I don't need help installing these things, but it might be entertaining to have somebody out to help. Frankly, the hardest part of the installation is that I'm going to want to paint the wall under the mounting plates of our original thermostats. The Nest gear is much smaller and I want it mounted without their big base plate.

"Hi, Mr. Installer Guy. Here's a brush and some paint. Get to work!"

(More seriously, I suppose I really should do the prep and paintwork in advance of installing the new thermostats, but that requires detaching the original thermostats and leaving them off for a day while the paint dries. And when exactly are we going to have a day when the weather is so absolutely perfect that we need neither heating nor cooling for a day? Should I just hope there's some slack wire in the wall, pull everything out, and let the thermostat dangle from the wires?)

It's just 24V DC. Hook up some speaker cable as an extension.

This is generally sufficient. At least, it is in my house.

Why yes, yes I am in the middle of painting.

Or just use the trim panel until a suitable day does come along, then you repaint and reinstall without the trim panel.

Confession: I am still using my trim panel, despite there having been an entire summer where radiant heating wasn't really useful

I haven't used the AC or heater for about three weeks now (but I was out of town last week). Yay Phoenix in the fall

Weirdly, here in VA we haven't used ours for the last month either! Our place retains heat really well, though, so mostly it just gets heated up by every day stuff like cooking (especially the crock pot) and laundry. Then when it gets too hot we crack a window. Usually I hate the temperature control in our house, but it's been wonderful this past month!

And we haven't used ours in the last two years. Oh, wait. We don't have AC or heat in our house.

The average daily high temperature, from coldest month to hottest month, ranges from 76 to 86 degrees F (24--30 C). In the coldest months it will drop down into the mid-60's at night. Mid November, 7am as I write this, it's 67 degrees outside. Our rainy season ended late this year (mid-October) and we will not see another drop of rain until next June. It's a tough gig, but somehow I persevere.

It's funny to see the locals outside when the temperature drops below 70 degrees, bundled up in hoodies and coats, with their dogs wearing fleece jackets. They look at me in disbelief when I tell them I used to walk my little miniature poodle at forty degrees below zero with no coverings at all, and he was fine with it, was willing to stay out longer than I was.

I am seriously considering [I have it in the budget] adding AC this Spring because while it might be 85 degrees outside, inside the house it will get up into the mid to high 90s some days because three of the four outside walls of the house are glass floor to ceiling. We would only need to use it for two months out of the year, for at most six hours per day. Those two months will double my annual electric bill, from $146 to $277 per year. Just as [more?] important as the cooling is the unit I am looking at claims to have highly efficient air filtration, which will help my wife's allergies. The claimed SEER factor of 21 is also appealing.

tanstaafl.

You need a Jeep. Totally impractical and tons of fun.

Well, that's not all that impressive then, is it?

Here, in the last month, it's ranged from 30F at night to 80F in the day.

So...ha!

It's kinda weird how the humans and other mammals adapt to different climates. I grew up in Colorado and generally disliked the heat in the summer, but it was never too uncomfortable. When it was cold, much like you I could be out in pretty low temperatures without a ton of layers on.

Five years in Austin, including during one of their record breaking summers, my body adjusted to the warmer climate. Every year when I went back home for the holidays, I noticed the cold bothered me more and more.

Now out here in California where the average is lower then Austin, I still find myself wearing a coat when others don't find it necessary, while also dealing with the "too hot" 80F occasional summer heat waves just fine. I'd come home and hear everyone else's AC units on, while I was opening windows.

Same here in Italy. Also, thermostats will turn of and on the main heater based on the temperature detected where the sensor is, that is, typically, the thermostat itself. Water temperature runnign into radiators is usually 55 Celsius degrees, here, but that is adjustable on the heater and never changed for the entire life of the system. So, yes, in such systems that is a "dumb statement". Temp you set on the thermostat will not affect how quickly heat is tranferred to the air in the house.

I've recently heard of some friends using the AC systems as heaters in winter (they all come with such feature). They all report not being particularly happy with such solution. Having hot air blow into rooms is usually not so pleasant, altough I suppose that is subjective to some extent. Noise is another complaint, if you're not using a good and quiet deivice. But, the biggest complaint seems to be that when you power it down temperature tends to drop quicker, mostly because radiators take more time to cool down, of course.

I particularly like the geothermal solution I've just learned about in this thread. I knew nothing about it, but it sounds actually smart, and makes so much sense.

I grew up in the great white north (most of my time was in north central North Dakota, with time in Alaska and Utah). When I moved to Phoenix, I didn't wear anything heavier than a flannel shirt all winter and use to smile at people wearing coats and carrying blankets to the Coyotes' games. We even went swimming in March in an unheated pool (roommate at the time was a friend from school who grew up in Chicago).

Not any more. If it is below 75F or so, I'm putting on sweatshirts or a light jacket. My parents claim I turned into a thermal wimp (they retired to Omaha).

Umm.. "The Great White North" normally refers to Canada, not parts of the USA.

Cheers

I say that being less than 75miles from the border (and it snowing from October to after Easter some years).

That's the "pretty good white north" zone. If you want "great", you have to cross the border.

Kooooo-loo-koo-koo koo-koo-koo-koo!

Hoser :-)

Though, mind you.. Give PM Harper enough time and leeway, and that point will be m00t.

But for now.. Take off, eh!

LOL. I just had to tweet that just now.

/r/askscience is tackling this question.
http://www.reddit.com/r/askscience/comments/mgwj4/which_is_more_efficient_keeping_my_house_at_a/

Here's a teardown of the thermostat for those that are into circuit pr0n:

http://www.sparkfun.com/tutorials/334

Mine have arrived. Installation will be this weekend, when I've got time to clean, prep, and paint the wall around the thermostat.

Yeah, not a teardown by someone with much of an eye for detail (no chips looked up for example) but nice pics nonetheless.

The strange optical thing facing backwards is an optical mouse sensor, used to pick up the rotation of the dial. That idea came to me when I was trying to work out how to make a standard IR quadrature encoder lower power...

Cute. The author claims there's Zigbee in there. We've got a "smart meter" on our house that speaks Zigbee, and I've got a not terribly clever battery-powered display that gives me data reported by the meter. Can my Nest (eventually) patch into this?

Can't really comment on that, apart from saying that Zigbee is a standards nightmare. Everyone appears to be running different layer2's over it...

This, and the licensing issues for an "open" standard map it even more irritating.

Woah. Though I can't help wondering whether it still comes out ahead if you factor in the carbon footprint of making an optical mouse sensor in the first place...

Peter

If you're trying to factor in components' carbon footprint, I imagine the energy saved over the lifetime of using the Nest (relative to a dumb thermostat) blows away the cost of the extra components.

Also, I imagine that Hugo's design will never fail during the service lifetime of a Nest thermostat. There are plenty of other things more likely to fail first, like the battery.

So has anyone got one working on a UK system yet ???

Cheers

Cris

Initial thoughts after installation:

- Of all the different cans of paint in the garage, none of them are the shade of green on the wall where the downstairs thermostat goes. This after I made a trip to Home Depot to get all the assorted bits and parts to fix up the paint job.

- So screw it, I mounted the Nests using the supplied mounting plate. Despite the videos to the contrary, it helps to have your own tools, particularly a needle-nose pliers and a proper screwdriver. For the upstairs thermostat, where there's wood behind the drywall, none of the included screws did the job, so I ended up having to use the longer screws that held in the original thermostat. (The non-Nest screws I used have larger screwheads than the proper Nest screws. This made it more difficult for the thermostat to fit onto its mounting plate. I had to push uncomfortably hard on it to get it to seat properly.)

- My wife **hates** the look of the Nest. Unlike the original white Honeywell box, the silvery Nest thing is quite obtrusive (to her); she feels like it's watching her. (It does remind me a bit of HAL 9000.)

- Setup is straightforward, but the WiFi support seems a bit wonky. I have my DrayTek base station upstairs and an Asus AP downstairs. For the Nest closer to my Asus, I typed my WiFi password twice and it never worked. I unplugged the Asus, forcing it to sync up with the DrayTek and it worked and appears to be continuing to work. It's the same password, so I don't know what's going on there. All our other devices seem to roam happily from one to the other. Only the Nest thermostat has had any issues.

- Pairing the thermostat with your account at nest.com is easy. The thermostat displays a code that you type into your browser. But... the first one never required me to type this in. Instead, nest.com's page, on my laptop, said something like "hey, I see a thermostat nearby!" and foomp, all paired up. How did that work? I have no idea. Maybe both were emerging to the Internet sharing the same IP address via my router and nest.com noticed this. I'm not entirely sure. Somebody clearly tried to be very clever here.

- The thermostats seem to be keen to save power by going to sleep and not phoning home. Maybe. Screen shot below.



- Check my network settings? Sure. Touching the thermostat causes it to check in and it's back online again. Otherwise, it's offline and there's no way (yet?) to queue a command for the thermostat when it comes back. Also, there's no way in the network settings to know which base station the thermostat's paired itself with. It would be nice for it to display the MAC address of the base station it's paired with so I can attempt to debug this.

- Programming the thermostat via the web interface is surprisingly klunky. They clearly want you to let the thing learn by itself.

- The feature I'm already missing from my $40 Honeywell thermostats is the ability to have it heat and cool without bugging me to switch modes. On the Honeywell, you can effectively program ranges that change over the day. So far as I can tell, the only range support for the Nest thermostat disables the learning / scheduling business altogether. If I could make one feature request, it would be to fix this. (This time of year, in Houston, temperatures swing from the 40's to the 80's, Farenheit, over the course of any given week, so it would be deeply annoying to be constantly flipping the thermostat back and forth from heat to cool to heat.) Never mind I'm probably one of three people in the world who actually figured out how to have my Honeywell actually do this and the Honeywell UI is totally garbage. At least it did the job.

- iPhone application, available today. Android application? Sorry, that will be out "in December". I'd be curious to know whether these apps speak directly to the thermostats or whether they're just pretty versions of the web page, where all communication between you and your thermostats is going through nest.com.

- This also raises something of a privacy concern, since Nest Incorporated clearly knows your schedule. I've read over their privacy statement, and it's pretty good. The only glaring flaw is that they claim they store my WiFi password on their servers. That's bad. My WiFi password should never physically leave my house. (It's different from every other password in my life, so the compromise of it wouldn't be particularly catastrophic for me, but it might be for others.)


Anyway, give me a few weeks and we'll see how well the learning works and whether the lack of auto-switching from heat to cool is a serious issue or not.

Thanks for the initial feedback. It's a bit disappointing to hear that there may be an issue with having to flip it between heat and cool modes. This is one of the primary reasons I wanted one.

At least it has the ability to be updated software wise to improve over time.

Looking forward to your further insights and thoughts about the Nest.

Sounds like a version 1 product. Most of the kinks will likely eventually get worked out if they ever make it to version 2

Incidentally, now that it's daytime, I'm not having these online/offline problems. Perhaps the thermostats were assuming "it's late, so I'll go to sleep and recharge my battery".

Or maybe.. "I'm new, my battery is low, I'll just sit and charge for a spell." ?

Curiosity: I've got my thermostats set to "turn on when approached", presumably leveraging the motion sensor. They only turn on, however, when I click them. Could there be a faulty motion sensor? How could I tell?

I read that part of the privacy statement differently. Its pretty specific that it's the thermostat itself that is storing the key.

The lower power objectives weren't for green reasons (pretty much the whole thing is "green" in that respect; a typical HVAC relay's pull-in current is at least double what the thermostat takes). It has to be low power because the whole thing runs from batteries.

Optical mouse chips are cheap, because they're made in such volume. They're pretty much 128x128 CMOS cameras with very cheap lenses

Likely bingo (though I don't know for sure)

That uses the short-range proximity sensor vs the PIR. Mine sometimes doesn't turn on either, but I've not worked out what the reason is. I suspect software updates will fix the glitches over time...

Here's the full WiFi language:
I'd say the text is somewhat ambiguous on *where* this stuff is being stored. Given that it's all "password protected", that would tend to imply they're talking about the server side, since there are no passwords in the thermostat.

As to the proximity sensor, I've discovered mine works, but only if I wave my hand a few inches in front of it. At 12 inches or more, it never wakes up.

As to the charging and network unavailability, I've noticed a pattern that they're unavailable at night and available during the day. I hope that the learning process can figure out that I'm more likely to want to dork with my thermostats at night, after my kid's in bed.

With a heating only, radiator based system, even if it does work on an electrical level, would it actually do anything that my bog standard 'stat doesn't?

We've only just turned our central heating on, it's been off since April. Even then, it's on for 2 hours in the morning and 4 in the evening.

Amusement du jour: got home at the Nest had an announcement on the screen that it had detected insufficient movement over the past few days to be able to confidently run its "auto-away" algorithm. (It's positioned in a central location. If it has roughly the same hardware as a standard security system motion sensor, it should be able to figure out when we're around.)

At this point, the #1 missing feature, so far as I can tell, are nerdy things. I'd like the display to be able to show me the various sensors as they're working. I'd also like the web interface to be able to graph things over time, like temperature or humidity. I assume the data is in there, somewhere.

Pretty sure the technical info screen will show you ALS, prox and PIR sensor readings (scroll waaaaaaay down). It used to, at any rate.

Yeah, I'd like humidity, temperature, etc logs too. I remember very early on (the office was a garage) building an arduino-based wifi temp/humidity/light/pressure monitor and loving seeing the humidity drop when the AC came on, etc.

The sensors I want are definitely nerdy: i still want a bluetooth prox sensor, because honestly, my or my wife's cellphone being there are the only triggers that really matter. Too bad leaving bluetooth enabled on the iPhone has an actual battery impact.

Yes, now that I know it's in there, I want to be able to get it out and graph it.

Seriously, it's so little power that it's in the noise. Leave it on, along with wifi. WiFi used to sleep at sub 1mA when associated to an access point, I believe Bluetooth was about 0.25mA.

If you assume that you have 100 hours standby with both wifi and bluetooth off, you'd have about 92 hours with both of them on. In the real world, where you do leave your house (hence wifi will be lower power) it's even less impact.

Really though, you should be using geofences to determine whether you're at home or not...

using geofences assumes something running on the devices and actively pushing info. i haven't put iOS 5 on either of our iPhones yet and am still waiting on an untethered jailbreak (or a different dam to burst first)

Yes, it needs something on the device, but it doesn't need to be running.

Even iOS4 apps could be woken by the OS when geofences were crossed. Pick the right level of granularity and it didn't even need to use GPS - it just got woken by the baseband when the local cells list (which is updated every ~2.5 seconds when the baseband wakes up to check for pages)... ie, basically zero extra power over standby.

Not that I've seen any geofencing app that works properly apart from reminders on iOS5, though... and that uses GPS

and even then the Reminders app doesn't seem to work very well for me anyway. Sometimes it will correctly remind me when I enter/leave a geofence, but more often it fails.

The issue I've seen with the reminders geofencing tends to be a difference in where the phone is told an address is (usually via Google Maps) vs where the actual address is. I need a way to override where "home" and "work" is, without having to change each individual reminder.

It's not terrible for where I'm at currently, but could see this as a real issue for some other properties. An apartment complex in Austin for example that has their front gate marked as the address, when all the apartments at the location are .5 miles up a private driveway.

Overall though, I've been quite happy with geofencing, (a feature a friend had on an old Symbian phone cira ~2003), and am glad to see it more widely adopted.

Just ordered mine, looks like they are sending out invites for the second batch today. Looking forward to it, since my current residence lacks a programmable thermostat.

http://www.sparkfun.com/tutorials/334

Tear down of the Nest device.

My Nest is now installed. Pretty painless, and the included wall plate helped to cover up the holes and unpainted spot from the old unit. Should be pretty easy to put the old one back in place when I move out.

So far so good. Will post a more proper initial thoughts and review after a few days.

So far so good. The unit set up a basic schedule based on when I was adjusting it over the first two days. It sets the heat up a little in the morning when I wake up, and turns it back down when I leave for work. Shortly before I arrive at home, it turns the heat up again, and down for bed time. It figured out the right time for this based on me physically adjusting the unit, or making adjustments from my phone.

Checking in on it today from work revealed it is now in auto away mode. This means it's unlocked the second tier of features and probably has a message waiting for me when I get home today.

Still a little bummed that when range support is on, it drops a lot of the learning features. Hopefully an update improves this. Much like Dan, there will be parts of the year where both the heater and AC are active over a 24 hour period in my place.

Either this is new, or I just wasn't paying attention. In the beginning, I thought that ranges were incompatible with schedules.

http://support.nest.com/customer/portal/articles/178899

Edit: in order to enable this, you have to go through a series of "are you really sure about this?" dialogs on the thermostat -- no way to do it from the web UI. Once ranges are finally set, the UI to program them is exceptionally klunky, but it does work, and now I've got everything set up with ranges rather than just purely heating or purely cooling. You'd perhaps think that the range view might merge the pre-existing heating view and the cooling view, right? Nope. When you enable the range mode, it's a completely separate program; you have to enter everything from scratch.

Sigh.

sigh.

I don't know how this is going to end, but one would have to imagine that Nest had a strategy for dealing with this issue on the way in, since they certainly could/should have surveyed the space of thermostat patents and been aware of the minefield that they were walking into.

One might speculate that what we're seeing now is the result of a patent licensing negotiation gone wrong.

This could be bad for existing owners, since part of the Nest magic is tied to the internet. Honeywell would have a hard time forcing a product recall, but could force the servers to go down. Would impact the ability to control it remotely, and also impact the thermostats ability to know the weather outside and forecast.

Really enjoying my unit so far. It's self learning has worked out well, and it should help to save a decent bit this summer when the AC is in use.

Knowingly infringing is liable for significantly more damages than negligent. It's usually better not to do the search first.

After replying I noticed Roger had already beat me to it. That's willful infringement if so and I think the penalties automatically triple. To start.

Hopefully some of those patents will go away thanks to prior art. The prior art may not be in the realm of HVAC, but it's hardly novel to apply the ideas to these products.

But even keeping to HVAC, the rotating control around a central display for instance goes back a few decades in thermostat design.

I'm not the biggest fan of the patent system in this country, yet some of those are hard to argue with. I will, however, argue a couple for fun:

• covers displaying grammatically complete sentences while programming a thermostat - This is one of those examples where I'd like for someone to explain why you can patent this.
• covers a method of controlling an environmental control system from a remote to adjust the settings of the system - I'm not 100% certain, but I really wouldn't be surprised if there were products that did this before that patent was filed. I don't know when Honeywell actually first released a product with such a feature, but if they weren't the first I assume this could be argued.

Ah well, I'm no patent attorney. I don't know the ins and outs of this stuff but it sure seems like Nest will have some problems.

I wondered about that too. I guess the key to the argument over that one is in the second half of that patent: "The display shows a change in a setting as the face is moved." We know what they mean for the Nest, but on those old dial thermostats did the "display" change or would they count the needle that pointed at the temperature as part of the outside dial portion?

I certainly understand the treble damages issue, and you can be guaranteed that the lawsuit discovery process will dig for any evidence of that. Nonetheless, you can imagine that they might have quietly taken a look and plotted a strategy in advance.

Once documents start hitting the courts, we'll know more about the case's back-story. This will be fun to watch. At the end of the day, the worst thing that's going to happen is that Nest ends up paying a royalty of some undetermined amount to Honeywell. I'd be quite surprised if Honeywell manages to get an injunction to force them to stop selling their product.

I really could not suppress the giggle that slipped out when I read the phrase "Grammatically correct sentences".

Presumably, grammatically incorrect sentences, would be OK.

I don't know when that patent was filed, but one of our buildings at school (in Prescott, AZ) (early 90s) had it's temperature controlled from Phoenix. I wouldn't be surprised if that was a Honeywell system, though.

The fact that you saw it a different way makes it even more questionable. You're reading that as "remote location," and I read it as "handheld remote."

My parents have bought a new apartment by the sea, which they frequent every weekend. During the week they leave the apartment uninhabited when they return to their other residence and so, especially during this time of year, they turn the thermostat way down.

My father was complaining the other day how he hates entering the apartment every week when it's so cold, and it takes about an hour or two to re-heat to a comfortable temperature. My parents don't arrive every week on the same hour, otherwise this could be fixed with a schedule.

I was thinking: what they need is a thermostat that can be controlled remotely. Either by sending a text message, or maybe there are units out there which can be controlled over the internet? I was wondering if the Nest thermostat was be able to do this? They have WiFi in the apartment, so if the unit is capable of connecting to this, then maybe this is possible? In essence, I'm not asking for much: simply a thermostat which can be turned on or off remotely so they can switch it on when they start their drive and then it would be warm by the time they arrive. Optionally, it would be nice if the temperature could be controlled remotely as well, but this would not be an indispensable feature.

Yes, the Nest can do this. They offer an iOS and Android app to control it via a phone/tablet, and it can also be controlled by logging in at nest.com. When setting up the thermostat, it will ask to join a WiFi network, and then help you bind it to a Nest.com account.

If the thermostat is mounted in a spot in the apartment where it's motion sensors can detect people there, it will also enable auto away mode. If they forget to turn it down one visit, it will do so on it's own if they want.

Very nice! Thank you! I only fear my father will believe it's too expensive only for this particular option...

It is a little expensive, but it's easily the least expensive option I've seen with the technology it has. I'm sure that's why Honeywell is so nervous. Everything they have that does the same stuff is at least $100 more and looks uglier.

How's this then? Price is about $100...

Edit: even though it seems to be a nice product which does what I need it to do, at an acceptable price, I'm out of luck since it seems to be a US-only product... (otoh, the same could be said for the Nest...)

A design that Honeywell did actually create first, as told here: http://observersroom.designobserver.com/alexandralange/post/reinventing-the-thermostat/31838/

Though the patents Honeywell is trying to sue over appear to be more modern then the initial round one given to Henry Dreyfuss for drawing a circle on a napkin.

Ooo, interesting. Not a bad price, and as far as thermostats go, doesn't look worse than the rest (they all pretty much look the same these days). Good find!

Very interesting indeed. This Filtrete thing connects to WiFi, supports fancier multi-stage systems and humidifiers, and seems to have some way of talking to your smart-meter (must be Zigbee) to tell you your power consumption.

Usability looks like a pale shadow of the Nest, but it's got a lot more functionality.

I installed one of the Filtrete thermostats in our warehouse. In this application, it's only regulating heat. I think it's a good product, but even I thought the wifi setup process was outrageously complex.

But, once it's online, you can adjust and program the thing from your web browser or iDevice. The website is simple to use and being able to program the thermostat online is fantastic.

Your web browser doesn't access the thermostat directly, so you don't have to open any ports on your router or anything like that. It seems that the thermostat polls the Filtrete service every few minutes. If you change the temperature online, it's not going to happen instantly on the thermostat. I would say it has a 5-10 minute response time.

http://www.marco.org/2011/12/17/nest-incompatibility-without-c-wire

I don't recall seeing this posted here.

Latest: I've now got my Nest programmed in "range mode", so it's got an upper and lower bound on the desired temperature at any time.

On Monday: the heat was running downstairs and up, which was fine, but the upstairs heat kept running well past the low end of the range I set. It ran the heat up to 81 degrees (I had it set to a range of 70-77F). "Gosh, it's hot", I thought, and went to poke at it to see what was going on, and it then switched to A/C to cool the house back down into the range I'd set.

At least the Nest got daylight savings day right...

I emailed Nest support and so far all they've done is ask "gee, has it happened like this before?" to which my answer is "go check all the historical data from my thermostat that you won't let me get by myself."

Sigh.

Well, no. It doesn't need to turn the circuit on to get power (in fact, it's the opposite: when the circuit is turned on, it *can't* draw any power). It seems that Marco's hvac relays are very low current, which means drawing the small amount of current which doesn't trip the relay on the majority of systems *does* trip his relay.

Still, the solution is the same - add a C wire...

Update: in the late afternoon (5-7pm) my Nest gets direct sunlight through the window. The black plastic of the Nest case seems excellent at absorbing all this light as heat, raising the thermostat some 8 degrees above the ambient air temperature.

After going back and forth with Nest tech support, it turns out that the Nest does include two ambient light sensors (one for visible light and one for IR) but they're apparently not attempting to do anything useful with those sensors, like try to model the degree to which the Nest might be heated by the ambient light. Instead, my Nest was predictably over-cooling the house and its reported ambient temperature matched precisely what my temperature gun measured on the surface of the Nest.

The workaround is that I've programmed in less cooling for that two hour range. It deeply disappoints me that my $40 Honeywell never had this problem but my $250 Nest does have the problem. Presumably, the cheap white plastic of the Honeywell reflects more light.

That's a rather seasonal fix. For just $4, Home Depot can sell you a can a spray-paint that will give you a year-round solution.

How about a motorized dolly system and some sensors to track the sun a move the NEST around your wall so it's always shaded?

Woke up to an e-mail from Nest that 2.0 is rolling out. This includes a new update for the thermostat, and the mobile apps on iOS/Android.

Added in is a new feature called airwave, among other things. Still a bit weird that my thermostat just gained a feature overnight, but also pretty cool.

http://www.nest.com/2012/04/05/nest_thermostat_software_brings_more_info_savings_access/

Dan, what smart meter do you have? The way you describe it, it sounds like you are referring to the power companies meter, rather than something you added. If this is the case you know of other add on products that could do this? Might be looking for something like this later in the year.

Altman, colour me interested in knowing more about my house's energy consumption. Be this Nest and other such devices talking to each other, or the data being pulled or pushed to a device* that can process and publish it.

*Said device should not be an always on PC, but a little shell script on a router. Or in this connected age, just a page in the cloud. And no I'm not fully thinking though the pluses and minuses, I'll leave that to smarter people than I.

So far as I can tell, the standard nomenclature is that a "smart meter" is a fancy computerized replacement for the traditional electrical meter that goes outside your house. I don't know who built ours, but it does have some kind of Zigbee wireless support.

A while ago, I managed to find the proper people at our power company and got myself a "remote display" (battery-powered LCD contraption, roughly the size of a cassette tape case, but thicker). There's a not terribly user friendly process where you type some digits from the back of the thing (a MAC address or something) into the utility company's web site, and then it all starts working. My particular remote display is manufactured by Honeywell (or really, some small startup that they bought).

Sounds like the hard part is finding the right people at the power company...Thanks.

Looks like the Nest has landed in Lowe's home improvement stores.

I find been stocked at a B&M store more impressive then been listed on the BestBuy website. If the stars align I'll be buying a Nest later this year.

I saw mention ins some thread, don't think it was on this forum, where they mentioned Nest 2.0 or some similar term, in the context of a newer product rather then the recent firmware, but didn't provide any additional information. Is there any such information in the public domain, or did I just get the context wrong, or "No comment" .

Edit: found it

So the above questions, but Nest + not Nest 2.0.

I know they did make changes to the mounting plate to make wiring even easier for the units being sold now. Maybe that is it?

Yeah, I think the change is just a tweak to the mounting plate. And they didn't fix my biggest complaint, namely that if you get the screw holes slightly wrong, you have no wiggle room to get the mounting plate completely level.

How are you Nest owners liking your thermostats?

I'll be moving soon, and would love to put a couple of these in. One to replace the main thermostat, and the other to place in the bedroom for proper climate control at night.

My main curiosity is the learning feature. I'm curious, because I'm skeptical that it could ever learn in a household like mine. My wife and I have ideal temperatures that are about 6 degrees apart, so we constantly want different temps. But even more relevantly, I simply do not have a normal schedule. I am never in or out of the house at the same time every weekday. Do you have any idea how the Next would adapt to me?

And lastly, can you turn the learning feature off entirely?

Still really like mine. A few new things have been rolled in like Airwave, and now monthly e-mail summary reports.

Can't comment on how two work together, I just have one.

Learning feature worked well for me, as it figured out my base schedule and when I tend to cool the house a little more prior to bed and raise it back up in the morning. Being able to edit the schedule on my iPad has been really handy, for the rare times I want to make a manual tweak. Auto away works well in my setup as well, for the erratic weekend or if I work from home a bit. No idea how it will work in your place, but it seems to be doing well here. It's figured out my AC system decently and shows pretty accurate estimates now on time to temperature.

And yes, you could just shut down learning entirely.

Attached is the daily energy report from my iPhone.

It's coming to Canada, so I may just pick one sooner or later. Mostly because it looks cool though. Even with a flexible scheduling thermostat I tend to keep it set to a constant temp, only making a small adjustment if I have a special requirement.

I also tend to keep it the same temp while I'm home, but I'd like to start having the system turn off while I'm not around.

I've always wondered, what's the threshold for energy savings? I have to imagine that reheating a place in the winter after you've been out must take more energy than maintaining a constant temp. So I wonder how long you'd have to be out in order to make it worthwhile. Sorry if I wasn't clear...

Didn't we discuss this upthread? I still reckon that, unless you've got a heating system that's more thermodynamically efficient at low outputs (eg heat pump), letting the place cool even briefly is a saving in energy, as the heat loss to the outside air is highest when the temperature difference is highest.

Peter

OK, one more time. Maybe I can say this better than I did before. Heating or re-heating, what you are doing is replacing the heat lost to the outside. The more heat you lose, the more you have to replace. And, as Peter said, the greater the temperature difference between inside and outside, the more heat you lose.

'Nuff said!

tanstaafl.

I'm sorry, I forgot we discussed this earlier. My bad.

Ok, I started looking at this again because I find the product amazing looking and full of promise. But the more I read the worse this product starts to look. And it looks great when you first see it. Which is the sum of the problem I have with it.

Looks great, but nothing special.

I can't find information about it being able to do anything at all that other run of the mill thermostats don't already do, and for the most part, have always done. There's a lot of marketing on their site and some BS too saying things like "other thermostats" along with some negative etc...

The thing is, that other plain-ol-thermostats already do a lot of what Nest claims as clever engineering, like running the fan after shutting down the furnace or AC.

Its biggest features seem to be WiFi, though that's just another way to do things manually for the most part, and its learning ability. The thing is, setting up a detailed 7 day schedule (that works) is pretty trivial on any programmable thermostat. For me anyway (probably you too). I know it's not for a lot of the general population.

It really looks like a basic thermostat with wifi, self-programming and a pretty shell. That famous lipstick-clad pig if you will. And while this one also has a pair of roller skates, it still tastes the same. It doesn't seem to have any non-basic features:

It doesn't support HRV (Heat Recovery Ventilation) systems.

It doesn't support control of (controllable) humidifiers. Or dehumidifiers.

It doesn't support scheduled or random or any fan control not already supported on every other thermostat available today (auto or ON is all it has). This is a HUGE deal when you're dealing with a mode-based thermostat (more below).

It doesn't monitor humidity and temperature outside.

No support for multi-location/zoned remote sensors.

It's primarily MODE-based operation (heat *or* cool) just like every basic thermostat out there.

In modeless operation, what they call "RANGE" (that is where you don't hard-set to cool or heat) you must program everything manually. Doh!


Here's a nice blog post at Nest alluding to the cluelessness: http://www.nest.com/2012/02/22/a-thermostat-just-a-thermostat/

People don't want Nest to interface with Control4 and Crestron so that it can control lights. They only want it to be a thermostat, but they want the rest of their system to be able to talk to it. The existing system will continue to take care of the lights and all the other stuff. Control4 and other automation systems can do things like open and close curtains, blinds, windows as well as turn on and off ceiling (and other) fans. Kind of important to have a thermostat that plays nice with your existing system if you're going shopping right?

Ease of programming is a great feature and shouldn't be overlooked because a lot of people don't know how to use a TV remote, let alone program a thermostat. Simplicity is hardest (but best) when accomplished through design. Simply leaving off core THERMOSTAT competencies however, is deletion, not design. It doesn't take any talent to do it that way.

But damn, it does LOOK amazing.

Not directly no. But when it's on WiFi, it pulls this information for the area via the internet.

Many of the other items on the list you already mentioned, and even seemed to discover they had plans to support some of it down the road.

I'm still happy with mine. It does more then the thermostat that was in place when I moved in. The old one had a fancy mercury based switch, connected to a coiled spring that was adjusted with a plastic lever. Oh, and a heat/cool switch along with a separate mercury based thermometer.

Does the Nest do everything? Nope. But like I said when I bought it, I wanted to support the concept as well as the current device. They had to start somewhere, and no product launches on day one with every feature in the world.

I'm not quite sure why you equate not wanting to add a photo display, clock or other features discussed in that blog article as cluelessness. To me, they were making the statement that they subscribe to the ideal of simplicity, something I'm trying to hold myself to as well these days.

Must be that time of the month to bash products?

That's enough for me!

I have a touchscreen thermostat with 7-day programming of four daily time periods (night, morning, day, evening). It's very easy to understand how to program the thing, but it's a huge PITA to actually do it. And it even has a battery so you can remove the control unit from the wall while you program it. But the interface is still awful and no fun to use.

I'll be happy to put a Nest in my next home (I don't plan to be in this one long enough to justify it).

It's attributing those things to people who have Control4 and Crestron systems that's clueless. Those people most definitely don't want Nest to do any of those things the author mentioned. Those people have automation systems that can already do absolutely everything. If they want a Nest, it's so they can tie it into the system to do what it already does, manage the thermostat duties of the premises, including reporting back to the automation system.

So the guy was either clueless about automation systems and the desires of their customers, or he was being disingenuous.

I brought up Nest because I've been wanting this kind of product for years, but I'm really looking to replace my existing thermostat with something that also has support for a few technologies mine doesn't - the things I mentioned. I have an HRV and humidifier that I have to use other controls for right now. I also run the fan manually to circulate air around the house which helps to keep a stable temperature in every room. It also helps to prevent certain rooms from getting stuffy because they may not see any traffic for extended periods of time.

It's a great basic product, but I feel let down because they're over promising and making it out to be of much bigger significance than it really is. But it's damn damn pretty.

What percentage of homes even have a home automation system to integrate with? I don't see it as being clueless to ignore perhaps 1% of the market (being generous there) which would add to the development costs. This is a startup product aimed at supporting probably 70-80% of the homes out there to improve their energy usage. Nothing more then that, until they can grow and justify the extra expenses of targeting smaller and smaller market segments.

But the guy was fluffing off the concerns of potential customers. I'm sure the percentage asking for the stupid/inane shit he mentioned were super low. Versus the many more who just want some slightly more than basic THERMOSTAT features, such as myself.

Personally, yes, it would be great to allow automation systems to tie into the thermostat, but that's not a stumbling block for me,so it isn't something I mentioned in my list. It's only mentioned in that blog post, out of context by its author, instead of addressing the real concerns of current home HVAC.

So Tom, you're absolutely right, but so am I. We're almost a year on with this product, so maybe they'll have new hardware around the corner. The scary thing is that some features, such as fan scheduling or randomizing (co-called "circulation mode" by some brands) can be accomplished as a software feature on the existing platform.

The Nest seems like it's intended to be retrofitted into an older house to replace a thermostat that's 20 or more years old. At least that's how their marketing comes off to me.

My house is far from state of the art in terms of HVAC, and Nest still can't say it's current with the technology I have. There are thousands of homes in my small town alone with the same technologies.

Here's a nice "dick move" by Nest: http://www.houselogix.com/dev/nestthermostat.asp

A third-party developed a commercial "driver" module for Control4 whole-home automation systems to talk via IP to Nest Thermostats. Nest asked them to stop developing it and remove it from the market.

I believe (along with many on the C4 forums) that the third-party used the word "ask" very liberally and kindly wrt to Nest's request.

Just starting to look at the Trane ComfortLink II. It finally looks like an iPhone-class Thermostat, compared to the Nest's iPod Shuffle.

[bait]So the Trane is GSM/CDMA and has a screen?[/bait]

But seriously, what are the differences?

In terms of HVAC standards, the Trane supports pretty much everything you can imagine. I just wish it didn't have such a huge screen. You don't need that for a connected device when you plan to primarily connect to it from another device. But if you planned to use it more stand-alone, I suppose the larger screen is a plus.

I'm still in love with Nest's physical design, I just think they didn't include enough in it to justify the price nor the praise - much of it can be addressed in software, but not all of it.

Back to looking at Thermostats (among other things) for some upgrades around the house to be done before the year is out. Since I'm running some wires and will be in the shared wall that currently holds our stat, I'm looking again.

Just saw this on Nest's blog: http://www.nest.com/2012/09/06/the-iphone-controlled-home/

They went to CEDIA. Wow, now isn't that irony. Just in case: CEDIA is the "Custom Electronic Design and Installation Association" - it's THE custom installer and home automation trade show. Nest stats don't work with any other systems.

They make a point of saying they like how a few other companies are also doing app-centric, non-integrated things and then they mention some examples, two of which (Lutron and RTI) most definitely integrate with environmental controls of other companies. For Pete's sake, the RTI screenshot they show in the blog even has an icon for Climate on it.

Why does such sexy hardware always have to be paired with such half-assed software? This is really what's been bugging me with Apple lately too. Software has really been going to shit over the past 6 years.

I've changed my mind as well. I thought the Nest looked really sweet, but I'm not going to be getting one. While I LOVE the physical design, I've come to the conclusion that I need to first think about what I want to do, then find the product that suits my needs. The Trane model you linked to, Bruno, is very nice, but it also doesn't integrate with many (any?) home automation systems like I'm looking for.

Instead I'm going to continue expanding my ZWave system with a compatible thermostat. I'm currently looking at this Trane, as it seems to be the best choice among the options available to me.

My goal is that I don't even have to be near the thermostat to control/program it, so in the end I've decided I don't really care what it looks like. I'm happy with it simply blending in with my wall.

Bruno, would you mind taking a look at that product and telling me if it has a decent compliment of HVAC capabilities? I don't know anything about that side of the equation (I probably wired the thermostat in my current place the wrong way ).

Before purchasing the Vera Lite for my ZWave system, the Nest was much more attractive to me. Now that I can start doing much cooler stuff with my system than I could before, I'm really excited to outfit the rest of my place with ZWave stuff...

My current fav among commercially available thermostats is the Filtrete 3M-50 Wifi Thermostat (aka. the CT-30/CT300E Wifi). It sells for about $110 at Home Depot in the USA.

I don't have one, but were I to purchase a new thermostat, that's what I'd get.

Instead, I've decided to just make one that works how I want it to work. An Atmega328p PIC (w/Arduino bootloader), LCD screen, some buttons, a couple of relays, RTC, temperature sensor, and either ethernet or an ElectricImp for remote access and easier programming.

Yeah, I'm weird.

Sounds like something we'd do at my work.

Certainly in the UK, most central heating controllers are completely un intuitive, is it really that difficult to design something that operates in a simple and logical manner?

(no in the answer because we did it many years back when my boss needed a new one!)

My problems are a) I need temperature sensors in at least 4 different spaces to get it right, 2) the central heating system / boiler only talks some proprietary RS-232 stuff (I assume there are no real, accepted standards), and 3) temperature adjustment needs to take into account wind strength and direction, as the north/south ends of the house let wind straight through, while east/west side walls are solid double-layer brick...

Yeah, I like that one as well. But I thought the Wifi version was the 3M50?. Anybody know what the difference is between the 3M40 and the 3M50? The website is not really clear about that.

Matt, the Trane Comfortlink II I mentioned before is probably best deployed when using Trane communicating furnace and AC equipment because they'll all talk to each other. There's also an adapter for regular 24v control which is required for non-communicating gear. I'm pretty sure modules exist to interface with commercial automation systems like Crestron and Control4, but I think it's more stat than I need.

The one you linked to sounds like it may do what you want and work well with your Z-Wave stuff. I'll have a closer look later when I can sit down, I'm kind of in and out at the moment.

For me one of the things I really wanted was a circulation mode for the fan so that I didn't have to leave it on all the time and so that it would come on at other times in addition to heat and cooling cycles.

The EcoBee gets a lot of positive comments as the best stat with wifi and web connectivity available to consumers. It does not have Z-Wave. It does have Zigbee which is currently used exclusively to talk to smart meters to monitor energy usage - which it can use for deciding how to run your AC, etc.

Took a quick look, but didn't find the level of detail for that Trane Comfortlink (the one from Amazon Matt linked) as I did for others in the Trane lineup. I know it requires an accessory module to support a dual fuel system if that's important to your installation.

The internet connectivity which they call Nexia, costs $9 per month. And the stat is Z-Wave ONLY, requiring a Nexia Z-Wave bridge to get it connected to your IP network.

IMO, it's doubtful that this stat will save you $9 per month over a more pedestrian programmable model, let alone the price of a Z-Wave bridge on top of that. IMO, EcoBeee seems like the leader in the web-enabled thermostat game at the moment.

Other than that, if it compares well in other areas to the Comforlink II, it's definitely a very capable device.

I'm pretty sure that the Nexia stuff is just if you don't already have something that can talk to it over ZWave. I'd be surprised if I couldn't just add it to my Vera Lite controller and get it working the way it's supposed to. But if it needs to talk to my heating/cooling system in a way that I can't provide with the equipment I already have, I'd be hesitant to get it.

I don't know how to tell what would be compatible with my HVAC system. All I want is something that will work with it, but also has ZWave in it. Apparently the Vera will work with Insteon and X10 products too, but those all seem to be even further behind, technologically.

Could turn out to be nothing, but...

http://www.engadget.com/2012/09/22/nest-home-monitoring-device-pops-up-at-the-fcc-with-zigbee/

Engadget says...



And I say... Not likely. At least not likely what this product is indicating nor geared for.

While there's an automation profile for Zigbee, Z-wave, which is not compatible, commands the lion's share of the home automation landscape. Zigbee however is popular precisely in the market this product covers, monitoring. Zigbee equipped smart electric meters have now been around a few years, and it's why the Ecobee thermostat also supports that technology. The Nest's WiFi radio already gives it all the communication capabilities it needs to join any home automation bandwagon.

I can see Nest releasing a replacement base plate (the part that gets the wires and to which the stat attaches) with built-in Zigbee plus a firmware update for the thermostat itself to allow monitoring energy consumption from the meter and use that information and time-of-use data to better plan its heating and cooling schedules.

EDIT: The image from the FCC is labeled as "back cover" in the official document, so it looks like it may be a new Nest main unit.

Yup, that's it. My bad.

Mark, our local (and small) Home Depot has that 3M stat (re-branded but logo-less) for about $100 at the moment. It may actually have been $89, but I can't remember at the moment. They had piles of them in a cardboard display box in the HVAC aisle a few days ago.

I just checked and it's not listed on the web site.

As expected, here's the new Nest Thermostat: http://www.nest.com/blog/2012/10/02/the-next-generation-nest-thermostat/

The whole Zigbee thing at the FCC was sort of a red herring because the original Nest has also always had it.

Looks like Nest now does 2 stage cooling, 3 stage heating, humidifiers and dehumidifiers. It's also 20 percent thinner than the previous model, but I kind of miss the fact it no longer has a black band around it.

A few of my wish-list items are taken care of with 2.0, including humidification and simultaneous heat/cool (maintaining automatic operation). Still too bad about HRV/ERV because I'd love to get rid of the separate control panel for that.

CAVEAT: The support for the extended HVAC hardware will only work with ONE of those pieces of hardware at a time. Nest is using a catch-all connector to support humidifier, dehumidifier, emergency heat-pump and third-stage heat. So if you have two or more of those capabilities with your current system, you'll need to pick only one for control by Nest.

http://www.nest.com/blog/2012/10/02/the-next-generation-nest-thermostat/

Second generation hardware is out with support for more HVAC systems. And software 3.0 is rolling out to all units. Biggest change for me will be the automatic scheduling support when in range mode (now called Heat/Cool mode).

You don't say?

The software update won't do much for me, since I have a more straightforward HVAC system. What I'm *hoping* they've done is souped up their logic for "gosh, the sun is shining right on the thermostat, so maybe I shouldn't trust the temperature reading". Right now, I have my Nest programmed for the late afternoon to tweak the temperature so it doesn't drive the house into frigid temperatures.

Also interesting, if you look at the new base plate, they appear to have adopted a small amount of wiggle room in terms of the screw holes. This is a big deal if you want to get the thermostat installed truly level. (Losen the screws a bit, tweak, then tighten down again.) Can't do that on the 1st-gen Nest.

Nice interview with Nest Co-Founder Matt Rogers by Kevin Rose: http://9to5mac.com/2012/10/02/nest-co-fo...ew-nest-launch/

You can listen to most of it in the background without watching the video.

Not related to the video, but another caveat with regards to humidification is that Nest doesn't have any external/remote thermometer to monitor the temperature outside your house. Internet weather forecasting isn't a suitable replacement for real-time measurement when you're controlling a humidifier trying to avoid dew-point issues like condensation. It seems like their humidifier control is mostly suited to the most simple manual units. Mine comes with its own automatic controller which monitors outside temperature and frequently samples the humidity of the return air duct - it's also able to humidify without the HVAC already running a heating cycle, by turning on the fan itself.

Somebody didn't read the manual when choosing that location for a thermostat. Or at least the manual for our current $25 thermostat clearly shows a warning against mounting where the sun can shine directly upon it.

Cheers

Yup, (un)like many things, you have to stick it where the sun don't shine.

Thanks for the set-up Mark.

My old house had the thermostat right behind where I put the TV. Running the TV screwed up the thermostat. My new house has the thermostat somewhere the sun sometimes shines. I suppose I could relocate it to the other side of the same wall.

What kills me is that Nest built in some fancy IR and visible light sensors. They have all the information they need to know how much heat the thermostat is absorbing from ambient light. Some poor schmuck just needs to run a bunch of lab experiments to come up with a suitable model. I wouldn't expect that from a $25 thermostat, but my expectations are higher for a $250 unit.

Ugh. My old place had that too. The temps were never right.

I think it would require more sensors and a ton of fuzzy logic to even get close to something useful in the sun detection and real-ambient deduction department. IMO, it would be a lot more cost effective and accurate to simply create/use a remote sensor.

I'd think if they had a $50 remote (wifi) sensor unit that measured ambient and exterior temperature they'd sell quite a few of them. It would be a nice extra revenue stream considering a thermostat isn't something a family is going to replace year over year like a mobile phone.

Don't make me go change the DB to have my post show up first
( Was going to add a comment about UBB.Threads 8 possibly offering a notice of a new post while composing. That lead to 20 mins of reading about 7.6 instead, and what now appears to be a dead product. Hrm, will have to ponder the future of the board software more later. )

It just dawned on me that the Nest always shows the SET temperature in a huge font in the middle of the display and the actual temperature in a small font along the peripheral, and not the other way around.

I can see this being useful while making settings, but when you're not touching the thermostat, I think it's going to drive me up the wall that the actual (measured) temp is not displayed in the center in the big font. When I'm walking by the thermostat or when I go look at it, it's because I want to know the temperature, not because I want to know what I had it set to.

I don't suppose there's any way to change this layout? I've seen at least a few other people mention they'd prefer it the other way round as well, but I haven't looked to see if there's any FAQ about it on their site.

Wow, really? That's annoying. In my experience, every other thermostat shows the current temperature. You'd think that they'd at least give you the option to change that...

If you are close enough to activate the near motion sensor, you should also be close enough to read both temperatures. The screen tends to not turn on with the far motion detector is activated, unless it's making a change (such as turning off auto away).

I think I can get used to it, but I can already anticipate my wife's going to have an issue with it and find it backwards.

From a usability perspective I probably would have done something a bit different while still trying to keep that ultra-mimimalist look. I'll reserve final judgement until I can get one of these bad-boys installed, but I suspect my idea would also be more intuitive when changing the set point.

Is anyone aware of something like the Nest or Filtrete/3M thermostats that works with line voltage (220V) electric baseboard heat?

I've installed Nests in my parent's house and just outfitted our warehouse with the Filtrete/3M model. I think both are pretty great and I would love to have them in my house. Unfortunately, I have electric baseboard heat. You would think this would be the easiest system to adapt to a wifi thermostat, but I can't seem to find a solution.

There is some mention on the 3M forums of adapting an electric baseboard system for a low voltage thermostat, but googling doesn't come up with much. Something that would sit between the 220V connection and Nest must exist. Right?

Wouldn't you just need a relay?

http://www.pexsupply.com/White-Rodgers-24A01G-3-Electric-Heat-Relay-240VAC-14415000-p

Yes, it looks like that's what I would need. Now I need to find one that wouldn't look silly sandwiched between my wall and a thermostat. It's probably more likely I would have to wait until someone makes a line voltage wifi thermostat.

I believe those are typically mounted in-line with the baseboard. You run the low voltage line to there.

I know the Nest cannot be directly communicated with via SMS, but could it be done indirectly via some gateway device? The use case here, and yes it is limited and so unlikely something that Nest would add, is for customers without a smart phone and wanting to let the Nest know they are coming home at a different time that normal, and therefore turn the heat on at an earlier or later time.

I don't see why not, if you have the capability to write your own interface. It should be somewhat straight-forward once you pass the hurdle of your gateway receiving the SMS data. After that you can pretty much write a script that interacts with the Nest site via HTTP.

The (huge) drawback is that since you wouldn't be going through any kind of API, once their web site changes you'll have to account for those changes in your script. So it can potentially lead to a long road of cat'n'mouse.

I just wanted to update that I purchased and installed that Trane thermostat (actually, a model slightly newer than that one). I had one major hurdle: no C/24VAC wire, so no power to the thermostat (and it doesn't come with batteries because they'd get drained in no time).

Thankfully, the HVAC gods were smiling on me, and I found that the line they ran from the furnace had four unused wires clipped back into the wall. So I merely picked a wire to carry my power, tied it into the other C wires back at the furnace, and used that. It worked like a charm, and now I can set my thermostat from anywhere! I love it.

The other night, my wife and I went out to do a trivia night with some friends at a bar. I turned the thermostat off when we left for the bar, but on our way back (the bar was about 30 minutes away), I set the thermostat to heat the house back up from the 67 degrees it fell to, and by the time we got back it was comfortable. Loving it.

Side note: I also installed a Z-Wave keypad lock. I can lock and unlock our front door from anywhere too

Matt, can you post the exact model number of your new stat?

Does anyone have or know if there are any coupons available for Lowe's for greater than 10% discount? The new Nest is supposed to be in stores now and I was thinking of possibly picking one up on my next visit to my US mailbox. I currently have a 10% off coupon for Lowe's, but I'd love to find one for an even greater discount.

Bruno, I got this model. So far, so good. Then again, it hasn't had to do a whole lot, since the mild weather here has meant we haven't really needed much heating or cooling.

That thermostat probably doesn't do as much, HVAC-wise, as the Nest does, but it does what we need. Our system isn't very fancy. However, I do believe I can use Vera to tell it what the outside temperature is, which can help in automating it. I could also do stuff like get ZWave door/window sensors, and tell my system that when it detects the windows are open, turn off the HVAC.

I'm not aware of any coupons. My wife and I got a 10% off coupon when we moved, and we used that on our new washer/dryer set to save a good chunk of cash.

Yeah, I also snagged a moving coupon from Lowe's for the next time I'm there.

Matt, did the whole Nexia (wifi web-enabled) thing end up being free with that stat?

I have no clue! I had no intention of using their Nexia service, instead using my Vera Lite from Mi Casa Verde as my Z-Wave hub. It's far more powerful and has a pretty active online community, including professional home automation installers.

I've been spending the whole day wiring in the second batch of ZWave wall switches. I now have almost one entire floor outfitted with ZWave control. There's a couple more lights on the main floor I want to add, then about four in our basement and 6-8 on the second floor. I already have over a dozen lamp modules, so I'm pretty set there.

So that means you're not getting any of the advertised web stuff with it then, right? Like temp/performance trending/graphs.

I suppose not, but I'm not really that concerned about it. I'll have to see if I can get that data through Vera or not. I suspect not, but again, that's not really what I'm in it for. I'm into the home automation side of things and integrating it with the rest of my system.

Understood. I was just trying to cover info for suggesting other WiFi enabled stats for friends who will definitely like the idea, but feel $250 is way too much to spend for something like the Nest or Ecobee.

Gotcha. Sorry, I'm not sure if there's a way to have both at the same time. I think I can only connect it to one service, but I'll investigate. I don't mind having more capabilities

Cool, let me know. None of my friends have any type of automation and I can't even think of one that's using a universal remote. Which is (insanely) hard to believe.

http://support.nest.com/article/What-is-Sunblock

(Sadly my Nest is sitting in a box. I can't hook it up in my new Seattle apartment due to an incompatible heating system.)

Wait... Seattle, now? Dang, you get around.

Welcome to the Pacific NW.

And here I was thinking that I might want a Nest soon, but balking at the $249 price tag. Any chance you'd want to part with yours? (Discount for it being a used item of course.)

(Or should I just bid on a 2nd gen unit on Ebay?)

Yeah, I referred him to my company. So we're coworkers now. (Let's go ork some more cows, shall we?)

I'll ponder this and let you know. It's a strong possibility I'll say yes, since I can't integrate it back into my place of living for a while.

If it's a Gen 1 unit, then never mind, Ebay has Gen 2 units in the 150-200 range.

This is a very good thing. I also turned on the new anti-humidity feature. I'll be curious to see how it works during days when we're away from the house and I set the house to "away" mode. Houston, in the summer, counts as a humid climate...

Houston, in the summer, I'm told, counts as practically underwater.

Data so far: I got rid of my custom schedule that compensated for the afternoon sun on the thermostat. Now, the "sunblock" feature is still "learning". It hasn't actually done anything intelligent yet. It's still overdoing it with AC for the hour that it's getting light. If it doesn't get smart soon, I'll go back to my old workaround scheduling.

Per the link above, sunblock may take a few days to learn and fully activate. Their graph shows two days of learning then activated fully on the third.