Wiring Problems with the RTH7400 - http://www.hvacmechanic.com/ Forums

Original message

volvoken

204.156.77.12

"Wiring Problems with the RTH7400" , posted Mon 21 Jan 14:25

I had an old General Electric Weatherington thermostat. I bought a new Honeywell RTH7400 yesterday and this is the old and new wire setup.

OLD:
O
G
Y
R
B
W
X2.

New.
I've installed the R to the R and I kept the R and RC jumper since I own a heat pump with Aux heat.

The Aux Heat works but when it's in Heat mode I get cool air. I installed the "W"hite to the "E" and the "X2" to the "E". Could you let me know if this is correct.

Replies:

Houston204

98.196.66.53

"Re(1):Wiring Problems with the RTH7400" , posted Mon 21 Jan 19:34

Old = New
O = O/B
G = G
Y = y
R = R & RC
B = C
W = Aux
X2 = E

You must also configure your new thermostat to match your system.
Option 170 = 7
option 190 = 0

"Tip of the Day" Remember to remove power first.

volvoken

204.156.77.12

"Re(2):Wiring Problems with the RTH7400" , posted Mon 21 Jan 19:54

Thanks I respliced the wires and all is working just fine, for the time being.