I have an older American Standard furnace w/ heat pump. When the outside temps drop below 30 degrees or so, the room temperature never reaches the temp the thermostat is set to. I know heat pumps only work down to a certain temp before the electric heat takes over.
Example: If i set the thermostat to 75 the room temp will only reach 73, or if I set the thermostat to 68 the room temp will only reach 66. Obviously this causes the firnace to run non stop. Any thoughts?