Came downstairs to find the Nest thermostat had a power error code - ran through all steps and still nothing. Just replaced with original thermostat and furnace still won't shut off unless we flip breaker. Any ideas? It's a little cold to have the furnace off for an entire night.
We've checked wires - they are in proper place and no visible shorts at the thermostat.
Had HVAC repairmen out about 5 days ago to replace draft inducer motor and housing. Seemed to be working fine until today as far as we could tell.
That's correct - the only way to get the furnace to turn off is at the breaker. Neither thermostat were able to control the furnace.
Pulled all wires, flipped breaker, furnace did not turn on.
CORRECTION - didn't see safety switch.
Pulled all wires and furnace DID turn ON.
All wires pulled at thermostat and furnace turns on when breaker reset.
I don't know if we have the energy or skill to accomplish that. We just tried to reinstall the Nest thermostat and it doesn't seem to be getting power. Without multimeter not sure how we would verify but I'm guessing we've lost power at the thermostat?
The thermostat and furnace are on different levels. We can trace the wires until they go into a brown harness and up into the ceiling and that's about it until they pop back out on the wall upstairs where the thermostat is.
Hang on. I just got the update where you made the correction. You are saying with the wires disconnected from the thermostat at the furnace itself and held in door switch the furnace DOES come on? If so you have a bad control board in the furnace.In otherwords wires are not connected to furnace but furnace runs?
Gotcha - ok.
No problem, I didn't see a good way to edit/correct the note. Is this a job for a professional or possible as a DIY project? Either way, do you have a ballpark for what it will cost to replace? Thanks!
Heil on outside of furnace
Inside: Inter-city products Corp USA
Model/Mfg No NTC5100BJC1
Thanks for your help!