Trane XR401 Help!

Old 01-20-20, 01:11 PM
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Trane XR401 Help!

Hi everyone, I have read a lot on hear but never posted. I bought a new house last week and my thermostat Trane XR401 was messed up (buttons were not responding) so I installed a nest 3rd gen. This has created issues. I have spoken with best support for about 4 hours to no avail. I have a XV 90 furnace, air controller, X14i compressor and heat pump. Basically when I set the temp to letís say 70, it never shuts off. The thermostat reads the temp getting warmer and above 70 but will just keep heating until I turn the system off. I have never owned a heat pump set up but I need help quick as itís 15 degrees here in Dayton. I have uploaded pic of original wiring.
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Old 01-20-20, 07:07 PM
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What wire on the old did you connect to the new?

It is acting as if the O (orange) wire is not in the O/B connector on the new thermostat and instead the white or black is. Otherwise you have a bad Nest - some are broken out of the box.
Old 01-20-20, 07:21 PM
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Welcome to the forums.

That picture is of no help. It can't be read.
You also have a dual fuel system which takes some special programming.

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