I have a thermostat that is completely blank (no display). I'd like to troubleshoot it myself even if I do ultimately hire a pro! We're in sunny southern california, so it's possible it's had no display for sometime, but when I first noticed it was after we flipped all circuit breakers to the house for another reason (checking power consumption). I'm ignorant of heating systems, but having done research, it seems that one of two things are most likely:
1. No power to main unit. Main unit communicates to thermostat via 24 V or lower. 2. Power to main unit, but no power from main unit to thermostat. Possibly bad connections, etc.
I'd like some ideas from a kind and patient soul on how to troubleshoot both of these.
Starting with #1.... The main heater is plugged in, but how the heck does one tell "it's on"? I see no lights, etc to indicate it is on. I have tried the socket it's plugged into and it's powered. However perhaps there is an on/off switch? The model # is MPGA075B4B. Originally, I thought the make was Honeywell because I saw that huge name on the on/off gas switch in the unit. But as I did internet searches, the name "Ducane" kept popping up. Not sure if these heaters are made by one company and use Honeywell switch or what is going on. Anyhow, I can't find a manual for it, and I can't see how to know if it's "on".
Number 1 seems like where I should start. Assuming the unit is on, my understanding is that one can check at the thermostat if it's even getting power.
a) How does one do this? b) assuming it is not, what next? Do you check the Honeywell switch on the heating unit itself? The Thermostat in the living room (that is blank) is Venter, Model T1050. There are 4 wires coming out. Red, Green, W1, and C (which looks blue to me!).
Finally, any other ideas? And I can post photos or more information.
I appreciate the help. Dave