Yesterday our a/c was working very well, but I could not operate the controls on the Honeywell programmable thermostat.
Changed batteries, nothing. It was not locked, could not get the touch screen to work, but there were numbers lit.
We decided to bypass the therm to test it, red to white worked. Realizing this was the heater control, I shut off power and jumped yellow to red, nothing. Green to red, nothing. Back to White to red again, nothing. I turned power on between each to check. I replaced all the fuses since I had extras anyway and it's not that. The fan motor is in on position, the fuse to the fan motor was replaced.
I can only assume that sometime between switching from red to white, to red to yellow, that the transformer blew a fuse or shorted out. The problem is, I cannot find it on my Rheem Furnace. CD6AXAD180E4AAA
I looked in lower panel and I see where the blower is and where the wires enter into the white plastic circuit board, but I cannot pull that out to test.
Husband is at store buying a ohm tester.
Can anyone tell me what the problem might be if its not the transformer and if it is, how to pull it to check and replace.