Appropriate wiring

2024011 · #1 Nov 8, 2009, 09:53 AM

I have a new RTH7500D programmable thermostat, On my old thermostat I have wire W2, Y, G, R, B, and X. I need to know where to connect the B and X wire.

KC13 · Nov 8, 2009, 12:00 PM

The new t-stat should have a terminal designated "O/B" - connect wire previously used on "B" terminal. "C" on new t-stat is probably equivalent to "X" from old one. You will need to access setup menu and configure "O/B" terminal to power reversing circuit in heating mode.



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