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rfl4
Aug 24, 2008, 01:06 PM
I just purchased a Honeywellrth7400 thermostat. I have connected this except for one wire. I have a T wire but cannot figure out on the heneywell where this goes. The only terminals left open are the Rc and the L

hvac1000
Aug 24, 2008, 01:19 PM
I just purchased a Honeywellrth7400 thermostat. I have connected this except for one wire. I have a T wire but cannot figure out on the heneywell where this goes. The only terminals left open are the Rc and the L



Old thermostat model number and brand?
Did you write down where the wire was rempved from the old thermostat?
Color of wire?

See T Outdoor anticipator reset

This doc

rfl4
Aug 24, 2008, 01:39 PM
The old thermostat is a trane weathertron. The wiring on it was O, B, Y, R, G, X2,W and T
The installation instructions do not show where the T wire would go. I tried leaving it off and the thermostat does not work.

hvac1000
Aug 24, 2008, 03:19 PM
The old thermostat is a trane weathertron. The wiring on it was O, B, Y, R, G, X2,W and T
The installation instructions do not show where the T wire would go. I tried leaving it off and the thermostat does not work.


Read this one

It says to tape off (T). Are you sure you do not have another problem. I never new a unit that required the (T) to be hooked up except for the original units the thermostat was made for. Do you still have the old Trane/GE units.

hvac1000
Aug 24, 2008, 03:25 PM
Question?

Did you have separate wires for RH and RC on the old thermostat?
If you did did you remove the jumper?
If you did no did you leave the jumper in?

Did you follow EXACTLY the diagram on page 12


http://customer.honeywell.com/techlit/pdf/PackedLit/69-1900EF.pdf

T-Top
Aug 24, 2008, 03:30 PM
You need a jumper wire from R to RC, X2 and W will go to the same place, T is not used cap off.