Heating, Air Conditioning, Fridge, HVAC/Thermostat Wiring


QUESTION: I had a new unit installed over the summer and it worked great until it got cold and my electric bill got high.  My old unit was really old and had an auxiliary heat source. My new unit is a single stage heat pump (all electric) with no auxiliary heat source.  My new unit was installed using most of the same wires.  I have an R, Y, G, O, Black (common), and White (Aux Heat) wire.  They are all plugged into my thermostat accordingly.  The problem is that my unit does not blow warm air until the Auxiliary Heat is triggered and takes forever to heat my home when the unit is only blowing neutral air.  Is there a way to rewire my thermostat so that the unit blows warm air every time the heat comes on?

ANSWER: Hi Jay,  First off the unit should always blow warm air when you are in heat mode. The thermostat wiring you are describing will not work properly on a heat pump. When the new system was installed did they put in a new thermostat?

Here's some things you can check. Turn the stat up 1 degree above room temp. then go out side to see if the heat pump is running (give it a minute or so to start). if it will not start then the stat wiring is wrong. If it starts check the temp coming out of the vents. If it is below 80 the heat pump needs servicing.

As for rewiring the stat it might be possible. If you can give me the name and model # of stat,furnace and heat pump that would help.

---------- FOLLOW-UP ----------

QUESTION: To answer your question, I did not have a new thermostat installed with my unit.  I bought a new thermostat about a month ago after I received an outrageous bill.

I'm not sure how to tell if the heat pump is running after I turn my unit on.

Hunter Thermostat: Model # 44273

Nordyne Single Stage Heat Pump: Model # GQ7RD-030K

Hey Jay,

What I have found out is you have a packaged heat pump unit, 2.5 tons with a 10 kw heater kit. With the stat set to heat mode and temperature set up 1 degree the fan on top of the unit should be running. That would indicate the heat pump is running.  Next check the switches on the back of the stat. there should be 2 switches, set the top one to H/E and the bottom one to HEAT PUMP SYSTEM. Also check the terminals to see if you have W1(this starts your heat pump), W2 turns the electric heaters on. There should a wire connected to W1.

What I think is happening, when the stat is calling for heat the blower that supplies air to your house starts but the heat pump does not start. That is when you feel the air is cool. After a set period of time the electric heater (AUX Heat) comes on.  

Heating, Air Conditioning, Fridge, HVAC

All Answers

Answers by Expert:

Ask Experts


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!

©2017 About.com. All rights reserved.