Have you opened up the unit to see if at least the red LED near the front comes on with AC? If not, measure the voltage at the large header with no jumper on it near the power jack in the back. You should see your AC supply voltage there. If you don't, work back to power jack and see if it is working. If you are getting supply voltage, then you need to measure the voltages at the 3 and 5 volt headers (they are the ones in the right back side of the unit). If you don't see these voltages but do see your AC supply voltage, chances are the MAX1631 is not operating for some reason.

We once had this very problem and it turned out to be some loose resistors.

Post what you can find and we can diagnose the problem further.

Stu