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Heating, Air Conditioning, Fridge, HVAC/Electric Furnace and AC condensor run at the same time.


I have a Gibson Electric forced air furnace in my new home. When the heat cycles on by thermostat control, the outside AC unit(Nordyne) kicks on also. It's about 30 degrees F outside. I felt the Hi-Low lines to the condenser, they are warm. It would make sense that heat is being drawn out of the house at the same time the inside unit is producing and blowing heat. It runs a hell of a lot to get up to temp. It can't be right, or is it ? I've always had gas furnaces, so this is why I'm trying to become educated. To me, it acts like a car's defroster that will use the AC to dry the air out. It is dry to a fault this time of year anyways, so I question the basic logic behind a household system needing it. Signed Puzzled in November. I haven't got the first bill to reflect the new cold weather usage. I'm preparing myself to freak out, so I don't freak out.

Hi Terry, good question. What you have is a Heat Pump system. It takes heat out of the outside air and transfers it into the house. I won't go to deep into how the system works, but if you want more info just google " Heat Pump".

Heat pumps are cheaper to run than propane or electric heat strips. Your furnace has heat strips to provide back up heat. As the outside air temp drops the heat pump produces less heat. Some heat pumps will shut down when the temp outside is say 30*. Doesn't sound like yours has the lockout temp switch.

I have been on many service call for this problem. Some times it is the "heat anticipator" in the stat. Send me the model number of your stat. Some times the problem is the outside unit (heat pump).

If your heat pump runs for more than two hours switch the stat to emergency heat.

Let know if you have any more question.

Heating, Air Conditioning, Fridge, HVAC

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Jim S.


I can answer questions on gas or electric furnaces, ac units and heat pumps. I don't work on boilers,chillers,or home appliances.


I have been in the HVAC trade for over 35 years. For the past 15 years I have owned my own business. I am semi-retired so I can answer questions in a timely manner.

I attended trade school for 5 years on weekends and evenings. This was very hard to do, but well worth it!

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