I recently installed a heat pump. When I turn the thermostat up more than one degree the heating source becomes the furnace, bypassing the heat pump. I understand that keeping a steady tempature is most efficient, however I like it "cool" in my house, but turn the thermostat up when company comes over. It is also contradictory to having a programmable thermostat. Is this now standard procedure with all heat pump installations? Thanks...Scott

DEPENDING ON HOW YOUR SYSTEM IS WIRED IS TO HOW IT WILL WORK IF YOU HAVE AN OUT DOOR THERMOSTAT INSTALLED IT WILL LOCK OUT THE FURNACE UNTIL IT REACHES THE DESIRED SET POINT OF THE OUT DOOOR STAT FOR INSTANCE YOU HAVE IT SET AT 30 DEGREES YOUR FURNACE WILL NOT COME ON UNTIL THE TEMP UT SIDE REACHES 29 DEGREES UNLESS YOU MOVE THE INSIDE THERMOSTAT TO EMERGENCY OR THE UNIT NEEDS TO GO INTO DEFROST

Sounds like your thermostat is not for a dual fuel appliation. Does the manufacturer state it is compatible with dual fuel? If so, sometimes a jumper on the board will have to be removed/cut or possibly a dip switch will have to be set. If you changed from an air conditioner to a heat pump most likely that's the problem along with making sure you have enough wires for a heat pump. On a single speed outdoor unit and a furnace, the wires for the heat pump are usually, R (24v), Y1 (compressor signal), O (reversing valve), W2 (secondary heat) & C (common).

This message has been edited. Last edited by: Dr Duct,

You most certainly may use a programmable thermostat as long as it uses intelligent recovery. This will prevent unnecessary cycling of your auxillary heat source. I too would suggest that an outdoor thermostat be installed and set at your homes balance point. The balance point is the temperature outdoors at which your heat pump can no longer maintain your indoor temperature without using your auxillary heat. Your installing contractor should be able to help you here.