Hey all,
I tried to replace the old mercury-switch thermostat with a new programmable one and ran into some problems, namely that none of the wiring seems to match either what the new T-stat expects OR what the air handler's documentation expects.
The old thermostat was hooked in with four of the five wires in the bundle, the Red wire going to RH (and also jumpered to RC), the Yellow wire going to both Y and W, the Blue wire going to O, and the Green wire going to G. The White wire wasn't hooked to anything.
The wiring in the air handler has the Tstat-Red wire going to a red wire in the air handler, as well as to another red wire in another bundle going out of the air handler, presumably to something outside like to the compressor itself. Tstat-White (not hooked at the other end) connects to a Airhandler-Brown, but the Compressor-White isn't hooked to anything. The Tstat-Yellow wire connects to Compressor-Yellow. Tstat-Blue connects to Compressor-Blue. Tstat-Green isn't hooked to anything, but Compressor-Green is hooked to Airhandler-Gray.
A chart:
I *Think* this system is a heatpump. It does have both heat and cooling.
I've attached pictures of the tstat wiring, the in-airhandler wiring (sorry the picture isn't great, phone's camera) and of the diagrams in the air handler manual for regular AC with heat (which I don't think it is), heatpump with no outside thermostat, and heatpump with outside thermostat. Any help would be very appreciated!
I tried to replace the old mercury-switch thermostat with a new programmable one and ran into some problems, namely that none of the wiring seems to match either what the new T-stat expects OR what the air handler's documentation expects.
The old thermostat was hooked in with four of the five wires in the bundle, the Red wire going to RH (and also jumpered to RC), the Yellow wire going to both Y and W, the Blue wire going to O, and the Green wire going to G. The White wire wasn't hooked to anything.
The wiring in the air handler has the Tstat-Red wire going to a red wire in the air handler, as well as to another red wire in another bundle going out of the air handler, presumably to something outside like to the compressor itself. Tstat-White (not hooked at the other end) connects to a Airhandler-Brown, but the Compressor-White isn't hooked to anything. The Tstat-Yellow wire connects to Compressor-Yellow. Tstat-Blue connects to Compressor-Blue. Tstat-Green isn't hooked to anything, but Compressor-Green is hooked to Airhandler-Gray.
A chart:
Code:
Tstat airhandler Compressor
R(RH,RC)--------R---------------R
B(O)----------------------------B
Y(W,Y)--------------------------Y
G G---------------Gr
*W* ---------Br W
(unhooked)I *Think* this system is a heatpump. It does have both heat and cooling.
I've attached pictures of the tstat wiring, the in-airhandler wiring (sorry the picture isn't great, phone's camera) and of the diagrams in the air handler manual for regular AC with heat (which I don't think it is), heatpump with no outside thermostat, and heatpump with outside thermostat. Any help would be very appreciated!
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