[heavyD]

Here is the wiring from our 25+ year old BDP (Carrier) unit with Bryant heat pump... Is there a thermostat out there to replace the original one?

The thermostat has the following wires... some of which I think I know what they are.

Here is the letter label and color for each wire:

Y---yellow---compressor for cool and heat with heat pump
P---blue--??
E---tan/brown---emergency relay for heat pump
C---light tan---common side
W1---white---heat
O---reddish---reversing valve on heat pump
R---orangish color--hot side
G---green---blower fan

[hvac1000]

A Honeywell 8000 series will replace that thermostat. I recommend getting a professional to install it.


http://customer.honeywell.com/techli...0s/50-9323.pdf

[heavyD]

Would the RTH8500 unit be the same unit as the professional model?


And any idea what the ballpark price should be for professional installation?

[hvac1000]

The manual

http://customer.honeywell.com/techli...t/69-1902EF.pd

Usually the cost of labor changes in many different parts of the country.

The thermostat you picked seems like it should work with no problems.

Look over the provided install manual to see if you can handle the wiring. If you can do it yourself.
It is easier for a pro to do the job and then it comes with a guarantee. But if you supply the thermostat there is usually no guarantee since they did not sell the thermostat.

[heavyD]

Thanks for your help... I've replaced thermostats before and it wasn't too bad. My only problem is where does the "P" terminal wire go on the Honeywell 8500 thermostat? Looking at the installation instructions it has only two choices either the "Rc" terminal or the "L" terminal?

[hvac1000]

I have no P designator so I do not know. Make sure it is a P