Have a multi-stage heat pump and this thermostat is one of the 3 located upstairs (there is one downstairs).

Wiring on T8001r was
Green = G
Blue = C
Yellow = Y
Red = R
White = W1

There were no other wires hooked up and no jumpers.

Installing the RTH7500 and I'm good up to the White wire. There is a note in the manual that states "If your old thermostat had Y1, W1 and W2 wires, stop now and contact a qualified contractor for help". Not sue if the key word is AND meaning that if all 3 were present to call a contractor. I'm thinking all I have to do is hook this White (W1) to Aux and run a jumper from E to Aux.

Does that sound right?? Sure don't want to blow the system up or burn down my house. Figured it would be easy to just switch out units since they were both Honeywell.

Wow. I was sure hoping to get at least one reply to this. I guess I'm giong to have to just try it my way or call an HVAC contractor out.

OK let me see and I can help you

White to aux should be fine. I don't think you will have a need to put in the jumper to e the way this is setup.