Go Back  DoItYourself.com Community Forums > Heating, Cooling, Air Conditioning, Ventilation and T-Stat Controls > Air Conditioning and Cooling Systems
Reload this Page >

Furnace warms to temp, but Compressor stays on and Aux blinking on thermostat

Furnace warms to temp, but Compressor stays on and Aux blinking on thermostat


  #1  
Old 12-28-12, 01:04 AM
R
Member
Thread Starter
Join Date: Dec 2012
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Furnace warms to temp, but Compressor stays on and Aux blinking on thermostat

I turn on heater when ambient is 55. I set it to 62. The house gets to 62 in about a half hour.
At some point, AUX flame starts blinking on the thermostat (it does not do that for at least the first few minutes). And the outside A/C compressor stays on - never goes off until I set the thermostat to OFF.

This did not happen last Winter. Bad thermostat perhaps?

Also maybe of note....the air coming out of the vents never really feels hot - just maybe lukewarm. Maybe that's more efficient as it brings the house to temp over a half hour rather than just blow hot air for a few minutes?

But the problem is really that the outside A/C never turns off on its own (even after a few hours)
 
  #2  
Old 12-28-12, 12:03 PM
user 10's Avatar
Member
Join Date: Mar 2004
Location: NA
Posts: 1,830
Received 57 Upvotes on 50 Posts
Do you have a heatpump with electric backup or a regular a/c?

55 to 62F in half an hour is very fast.

62F is a very low normal setpoint.
 
  #3  
Old 12-29-12, 11:08 AM
R
Member
Thread Starter
Join Date: Dec 2012
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
No. Nothing we'd consider "AUX". Just a furnace in the attic and the compressor/condenser unit out in the back yard.
The furnace does get the house up to temp fairly timely.
I guess my concerns are that when I put my hand up to the vents, the air is not super warm, just lukewarm. And that the compressor doesn't shut off (and AUX is blinking).
 
  #4  
Old 12-29-12, 01:50 PM
F
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 16,321
Received 39 Upvotes on 31 Posts
You didn't answer the questions, do you have a heat pump? (It sounds like you do.) IF you have a heat pump do you have electrical heaters in the air handler for emergency backup heat or do you have a more conventional gas-fired furnace for back up heat? Until you answer these questions no one can help.
 
  #5  
Old 12-29-12, 02:24 PM
R
Member
Thread Starter
Join Date: Dec 2012
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
No, we do not have a heat pump. :-)
And nothing electrical for heat or cooling other than to operate the motors and compressor.
There is the furnace in the attic.
Outside is (what we call) the air conditioner. It is a conventional central air conditioner. Filled with refrigerant with the compressor and such.
 
  #6  
Old 12-29-12, 02:45 PM
F
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 16,321
Received 39 Upvotes on 31 Posts
Either the thermostat is toast or it was miswired or misprogrammed.
 
  #7  
Old 12-30-12, 04:23 PM
user 10's Avatar
Member
Join Date: Mar 2004
Location: NA
Posts: 1,830
Received 57 Upvotes on 50 Posts
Continuing to operate the system like that will completely wreck your a/c.

Shut off the power to the a/c unit and call for service.
 
  #8  
Old 12-30-12, 05:54 PM
R
Member
Thread Starter
Join Date: Dec 2012
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
I think I found the problem, with your help

I don't have a heatpump, and have not had this behavior before where the outside unit (AC compressor?) would stay on.

But I did remember something about a heatpump setting when the installers put this unit in a couple years ago.

I pulled the thermostat cover, and the selector switch was set properly to SS (Single Stage). So that was OK.
Hmm....looked on the Internet for a manual and found one. (insert forehead smack here)

Turns out that there is ALSO a software/programmed setting for HP or SS, and mine was set to HP.

I am not sure why there is a physical switch AND a programmable setting, but setting it to SS to match the switch seems to have fixed it.

Thanks for the pointers!
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: