Heat Pumps and Electric Heating - Turned on Heat, compressor is running

I turned on the heat for the first time this season and the compressor runs when the heat comes on.


http://www.flipdrive.com/showpic.php?album_id=4&name=thermostat+-+open.jpg
I opened the thermostat, blew the dust off, but didn't see any loose wires. This system is approx. 20 years old but has been running fine up to this point.

http://www.flipdrive.com/showpic.php?album_id=4&name=compressor.jpg
I'm getting heat, its just that the compressor fan runs when the heat turns on.

Thanks for any suggestions.

what kind of furnace do you have? Do you have a heat pump or straight A/C?

Need more information such as why type of tstat, OD unit, air handler, etc. Is the indoor blower running? How do you know both the compressor and fan on the outdoor unit are running? Any relays clicking or not clicking that should be? How handy are you with a multi-meter?

:confused: I jumped the gun and thought it was working again. The blower was running without the fan in the compressor running, but now I see that both are running again. Maybe when I tripped a mecury switch when I was blowing out the dust in the thermostat??

The unit is a heatpump.
The thermostat is a Honeywell HQ711597HW.
-T874 Multistage, Q674 subbase (from online manual)

I can use a multimeter with general electrical situations, but I'm not a pro.

I'll have to review your questions again to see if I missed anything else!

Thanks for reviewing this.

addendum:

The fan on the compressor is running, not the compressor itself. The blower in the furnace is also running. I'm getting heat, but the fan on the compressor shouldn't be running.

FYI: The A/C works correctly. Its just the fan on the compressor running during heating when it shouldn't be.

Do I need to get more information to make this more helpful?

Sorry for my ignorance.

addendum:

The fan on the compressor is running, not the compressor itself. The blower in the furnace is also running. I'm getting heat, but the fan on the compressor shouldn't be running.

FYI: The A/C works correctly. Its just the fan on the compressor running during heating when it shouldn't be.

Do I need to get more information to make this more helpful?

Sorry for my ignorance.


If the fan on your compressor is running during heating when it shouldn't then what kind of heat do you have? Can you give us a rundown on what your system is? This is the heat pump forum after all.

Your compressor and fan should be running when using the heat pump for heat. The only time it wouldn't is if you have a natural gas furnace that runs below a certain cutoff point.