Fix for JCI wall mount thermostat ns-btb7001-0

[Old Sparky]

Hello
    We have hundreds of JCI thermostats in the buildings where I work. It seems that after every power outage, there are a few that don't come back to life. There is a capacitor, C25, that is the problem. It's on the backside of the board, near the bottom left. Re-soldering it usually fixes the problem.
    What happens is the cap is part of the Reset circuit for the microcontroller. The cap gets lossy and doesn't let the voltage across it get up to >4.5, so the microcontroller doesn't wake up. Re-soldering it eliminates the leakage. A bad one will measure about 5K ohms, a good one will be about 12K or so. The cap value is about 0.1 uF.
    I've fixed about a dozen of these with no further troubles. It only takes a few minutes.