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Mark Henley
Mark Henley, Journeyman Technician
Category: HVAC
Satisfied Customers: 3217
Experience:  UA Journeyman Pipefitter , HVAC, Refrigeration, DDC controls. 26 years.Commercial & residential
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I have a very old thermostat (GE Weathertron 3aat80b1a1 - yes,

Customer Question

I have a very old thermostat (GE Weathertron 3aat80b1a1 - yes, it's GE, not Trane- i guess Trane bought Weathertron at some point?) that does not have wires labeled. They're soldered on, and not even all distinct colors (2 red, 2 black, 3 tan).<br /><br /> i bought a Honeywell TH6220D which i believe should handle my heatpump (it has AUX heat and EMG heat, along with AC). I have pictures of the existing wiring i can upload (not sure how to do it on this post) or email. I just need to ID the old wires. <br /><br />Without a pic, the best i can think to describe the layout is this: 2 tan and 1 black going into the lower mercury cylinder 1 red 1 black and 1 tan going into upper mercury cylinder 1 red going into some kind of capacitor(?) right by the upper cylinder. <br /><br />The new T-stat's terminals per the manual are: <br />R and Rc jumpered together - power <br />Y - compressor C - 24VAC common <br />O/B - changeover valve <br />G - Fan relay <br />AUX - aux heat relay<br /> E - Emg heat relay<br /> L - sends output when set to EMG heat<br /><br /> any help please?
Submitted: 7 years ago.
Category: HVAC
Expert:  Mark Henley replied 7 years ago.
Chat Conversation Started
Mark Henley :

Hi, are you sure you are getting to the back of the thermostat, they won't be soldered in there, you are looking at the factory solders of the internal thermostat, you need to get right where the wires come through the wall, let me know.


ah, apparently there are 2 parts to this thing. I unscrewed the second face and got to the labeled wires. This is what i got:


R-Red ; T-Brown ; O-Orange ; G-Green; Y-Yellow; X2-Black; B-Blue ; W-White. Based on other research i've found most of how these would translate but not 100% sure.


oh yea, and W is i would guess jumpered to U.. they seem to be connected anyway.

Expert:  Mark Henley replied 7 years ago.
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Your expert is gathering additional information and will be back with you shortly.
Expert:  Mark Henley replied 7 years ago.

Hi , sorry for the delay, U doesn't need to be connected nor does the T. , W would be AUX and X2 is emergency or E, let me know.



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