when the outside temperature reaches 30C and the aircon conks out with heat exhaustion

Oh, to live in merrye olde England!

It's usually about that hot outside when I get up in the morning, before the sun has had time to bake into the asphalt and concrete. It sounds like you need to import a quality American A/C.

But at least the humidity here is greater, too. (Well, at least today: my dewpoint is 74F/23C, yours 50F/10C.)