We bought a Honeywell model rthl2510c thermostat to replace a GE weathertron thermostat connected to a trane ex1000 heat pump. Only the booklet does not have a good reference for the wiring. We have R, T, O, G, Y, X2, B and a W for wires. The booklet mentions nothing about the T or the X2 connectors. Please advise. The Honeywell showsB,O,G,Y, (W/Aux) and a (Not used under one of the connectors), R, RC
Hello,The T wire is no longer used and can be taped off.The X2 is commonly a second stage heat like electric back up in indoor unit. Do you have just the heat pump or do you also have electric strip heat?
I don't know. I just bought the house 2 wks ago and the previous owners gave me no books. I just wanted to update the thermostat.
Can you tell me any tags you see on the indoor unit?Then I can see if you have electric heat
The tags are faded. It's too hard to read numbers. It is a GE unit build 4/83.
Thank you.If the X2 was attached I have to assume you indeed have back up heat. The issue is this new thermostat does not handle back up heat. It is only good for standard one stage heat pump.It will work with the X2 unhooked and taped off for cooling and for first stage heat but will not be wired for auxillary heat.If you want a fully functional thermostat you must get one that is compatible with auxillary or back up heat.Billy
The X2 was attached but the booklet that came with the Honeywell thermostat has advanced installation information on pg 24 stating it's for heat pumps with auxillary or backup heat only. I was unsure about the T (black) wire.
The T wire is an unused anticipator wire that is no longer utilized by newer thermostats.The T can be taped off and not used.Billy
Ok...thanks. So here is what I have for wires currently connected:
Red to R (should be jumoer in place r to rc)Black taped offOrange to OGreen to GYellow to YBrown taped off for nowBlue is taped off and not used (old common wire not needed with batteries)White to W/AuxThen set thermostat menu for heat pump
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