I have a TRANE XL1200 Weathertron heat pump with auxiliary heat. It is controlled by a Trane 3AAT80A1A1 mercury bulb analog thermostat. I have purchased a RiteTemp 8050C digital programmable thermostat to replace it. The analog thermostat has wired terminals marked O,R,T,G,Y,X2,B,W and F. It also has a terminal marked U that is jumpered to the W wire. The RiteTemp digital has terminals C,W2,Rc,O,B,Rh,W,Y,G, and A. The digital thermostat has documentation suggesting how to connect the wires. The RiteTemp documentation maps the wires this way:

Trane to RiteTemp

Connect G wire to G terminal (this connects the fan)
Jumper W terminal on RiteTemp to Y terminal on RiteTemp
Connect Y wire to Y terminal (this connects the compressor)
Connect O wire to O terminal (this connects chang over valve)
Tape off the B wire
Jumper Rc terminal on RiteTemp to Rh terminal on RiteTemp
Connect R wire to Rc terminal (this connects to the 24vac power)
Connect W wire to W2 terminal (this connects auxiliary heat)

All of this is fine, but there are wires left over from the old thermostat connections. I don't have any documentation for the Trane thermostat so I don't know the function of each wire. The left over wires are T, X2 and F. The RiteTemp documentation implies that anything with an X is a control wire and should be connected to an AC (current) terminal so I guess I could connect that to the C terminal on the RiteTemp. That still leaves the T and F wires.

Any advice? Thanks.

X is common, probably not needed. X2 I think is for a diagnostic light I=on old stat, not needed. F?? don't remember ever seeing that before, E maybe? I'm comfused about W to Y though. But I won't deal Rite temp stats, I've posted several messages about hardware store bargain stats.

I just got that tstat a week ago, but I live in Florida and only had to install it on a A/C unit with the indoor part of a heat pump. My only wires were W, Y, G, and RC.

I just got that tstat a week ago, but i live in florida and only had to install it on a A/C unit with the indoor part of a heat pump. My only wires were W, Y, G, and RC.
You have a completely different animal.