[shanbrt]

I have no power to my thermostat ( between lugs R and C) The screen is blank.. I have checked all circuit breakers and i dont know where to go next. Does this heat pump have a internal fuse that i can check? Any help would be greatly appriciated!!! I dont know the model of the heatpump...
Thanks, Shannon

 

[wirenut1110]

In your AHU, you should have a transformer in there stepping voltage down to 24 volts. There may be a fuse and some have a little circuit breaker on them.

If the fuse is blown, you may have an issue that caused it to blow like a shorted relay coil, reversing valve coil, bad t-stat wiring, etc. or the transformer itself could be bad.

 

[dac122]

Look for power from your transformer or a blown fuse. If the fuse is blown then try replacing, but if the transformer is blown or if you fuse blows again you'll want to know why before proceeding.

 

[shanbrt]

What i found

I got up in the atic again and started looking around the air handler unit and noted water in the drain pan. there is a switch in the bottom of the pan in witch i think may kill power if water builds up in the pan. i vacumed up all the water ( not much) and cleaned the moisture of the switch and it started working again. I blew out the drain line from the coil pan and all was good until i got home from work today. The pan had water in it again and there wan no power to the thermostat. Any ideas what could be causing water to build up in the lower pan?(not the coil pan)