I am trying to install a Hunter model 44860 thermostat. I have already installed one on the my downstairs gas heating/ac unit, and it works well.

I am now trying to get the second one to work on my upstairs unit, an old heat pump with emergency strip heat. This heat pump is an Amana, and is about 21 years old.

My local heating / Airconditioning person came and installed the Hunter 44860 thermostat, but it did not work. It went into cooling mode, no matter if we were requesting heat or AC. In the SYSTEM menu, we selected "Heat Pump".

He said this thermostat unit wants to control the reversing value, using O and B, and that my old heat pump does this itself using onboard circuitry, not the thermostat.

It would seem to me that since the reversing valve control is done on the heat pump, that the control of the unit would be even more simple than standard heat pumps, and perhaps more like "conventional heat".



Below is a picture of my current wiring scheme on the current thermostat. It is a Honeywell model Q674F1022.

Please see a picture of the current wiring at :

New Page 1 (http://host.fptoday.com/hrbc/hrbc/my_therm.asp)

A picture of the connections for the Hunter 44860 is on the same webpage.


Please give me any advice toward what arrangement of the current wires will allow me to use the Hunter model 44860. I want the emergency strip heat to work also.

thanks
Homer_at.

Look here for the wiring diagram for the old Honeywell unit.
This will explain exactly what wires are supposed to be connected to what.

http://customer.honeywell.com/techlit/pdf/69-0000s/69-0012.pdf

I have to say this Hunter thermostats are junk. Now that that is said read more below.

Why in the world are you putting a heat pump on a set back thermostat if that is what you have. More energy will be used to bring the temp back up after the set back because the resistance heat will usually kick on spinning the electric meter around. Just had to add this.

Now to the wiring. You will need to look at the old wiring diagram that I provided to see exactly how the old thermostat was handling the old outside part of the heat pump.Then cross the wiring over to the new thermostat.
Cross your fingers and hope it works.