Help changing 7-wire thermostat to digital

Old 05-17-23, 07:57 PM
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Help changing 7-wire thermostat to digital

Upgrading heat pump (Trane Model TWV024B140A1) with new Honeywell Home T3 programmable thermostat. Usually I just put each wire into its corresponding new location but some new wire locations have different or missing labels. The G,Y,R,W wires are obvious but the O,B,T wires have me puzzled. A couple questions: 1) I found a different model reference that advises place O (orange) into the O/B slot and the B (blue) in the C slot. Is that correct? 2) where should the T (brown) wire go?

Old 05-17-23, 10:15 PM
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You are right O is O/B and Trane B is Honeywell C.
Tape off the old T wire.


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