installing thermostat honeywell rth 7500d

Old 12-06-14, 04:34 PM
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Question installing thermostat honeywell rth 7500d

hi , need help to install a new thermostat Honeywell rth 7500d how to do the wiring, you find attached a photo of my old thermostat , thx a lotName:  thermostat.jpg
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Old 12-07-14, 01:35 AM
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Lennox used an odd color code in the 80's.

old = new
R = O/B
Y = Aux/E
X = C
F = G
V, Vr = R , Rc
M = Y

You must also configure the new stat for heat pump with Aux heat.
170 = 7
190 = 0


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