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Hi I'm Brian and I'm here to help!
Can I get the model number of your old Honeywell thermostat please? It would also be helpful to know what color wires go to what terminals on your old Honeywell too.
I am not familiar with that model number for Honeywell. Honeywell's model numbers typically begin with T, TH or RTH then at least 2 numbers but usually four. Is your old thermostat a digital one or older analog mercury style?
I'm not sure why but no photos are posted on this end. Regardless, your wiring is a simple as it gets and sounds right. If by chance there are two R terminals (R, Rc and/or Rh), make sure the two of them are jumpered together in the case that the jumper may have fallen out. Also, many electronic thermostats that don't have a C terminal (24volt common), use only batteries to power them. If that's the case, you should check the batteries are new and the battery contacts are shiny and clean.
So that tells me you have an electronic thermostat. The front and the base connect with pins on the front that plug into a socket on the back and it's important that the base is mounted flat, the pins on the front are straight and clean and the two mate together solidly. The lit lcd display on the front part of the stat should <WORK> even if it's not on the base as long as the batteries are in, good and making good contact.
That would mean it is what's called a 'power stealing' model. Honeywell made many of those. My best guess is that for some reason there is not 24 volt power on the wiring at the thermostat. We can check that though. Remove the face of the thermostat to reveal the wiring terminals and jumper R to G with a small piece of wire or a bent paperclip or the like. Even two small screwdrivers criss/crossed and touched to the two terminals at the same time while contacting one another will work. Your indoor blower should start when you short R to G. Let me know what happens...
Ok, now try to jump R to W and your heat should come on.
Hmm there may be a separate issue with your furnace. I would try power recycling the furnace again. It would appear there is more going on than just the thermostat.s
With the thermostat in the off position, you do have at the very least some power going to the thermostat, it should light up. I don't really understand why it's not. Do you by chance have a volt meter to read 24 volts ac?
Well, I'm afraid I'm at a bit of a loss too. It sounds like the issue may be in the furnace itself. Perhaps a safety tripped during all this or something similar. The fact that the blower ran at least once when you jumped R to G tells me you have 24 volt ac at least in some places (maybe not all that there should be). It tells me power to the furnace is ok. It's hard to trouble shoot from here without a meter. I'm sorry I couldn't be more help!
You're welcome. Best of luck with the tech tomorrow.
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