I replaced my old GE weathertron thermostat model bay28x138 by a new honeywell rth7500d. The wires . The letters on the old GE are f, b, g, x2, y, w, t, o, r. The letters on the honeywell are c, g, y, o/b, rc, r, aux, e, l. The t connection on the old weathertron GE thermostat seems to have no possible connection on the new programmable honeywell rth7500d,what do I do with it? And I have jumpers between x2,u and w on the old weathertron bay28x138 wich was installed 35 years ago as an original thermostat for the GE thermopump there is no wire connected it's f connector.
Can someone help me please?
Alain

r to r
x2 to L
g to g
Y to Y
b to c
w to aux
o to o
then jump aux to e

r to r
x2 to L
g to g
Y to Y
b to c
w to aux
o to o
then jump aux to e

thank you but I still don't know what to do with the "T" wire from the old thermostat,do you?
Also I had connected my old x2 wire to "E" was it wrong? Can it damage the new thermostat?
thanks again friend
Alain2010

T isn't used, tape it off. Check out " Lux Products cross reference chart". It will tell you what goes where.