Heat and A/C on Concurrently!?

Reply

  #1  
Old 07-20-14, 01:01 PM
Member
Thread Starter
Join Date: Jul 2014
Location: USA
Posts: 3
Received 0 Votes on 0 Posts
Heat and A/C on Concurrently!?

-Goodman heat pump system model AR36-1 (Not sure on the heat package, but 4 coils)-

While my thermostat calls for cool, the blower comes on, hot air comes out first for a minute and then cool air follows. The cycles seem shorter but much more frequent than normal. Anyway, when I checked the air handling unit in my attic, I found that it was super hot, so I know my electric heat strip is kicking on in addition to the a/c (a/c pipes are cold). I thought it might be a stuck sequencer, so I replaced both of them, but it didn't change anything. I was out of ideas so I had an hvac technician come over and he said its because I didn't use the exact Goodman replacement sequencers. He said he'd come back over, but never did so I thought I'd just do it myself, per usual. When I replaced the sequencers with the exact Goodman part, the same thing happened--hot and cold together. This has been going on for the past 1-2 months. Last week i decided just to forget about fixing it altogether, but today I opened my $400 electricity bill!!! For comparison last year for the same month was $90. Any ideas are welcome. Testing protocol would be really helpful.

I should also mention that in the last year I've replaced a capacitor, the blower motor, and the transformer, so I thought I could have messed up the wiring somewhere, but the HVAC technician said everything was wired fine.
 
Sponsored Links
  #2  
Old 07-20-14, 02:06 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,373
Received 10 Votes on 8 Posts
http://igate.northernplumbing.com/pa...manMfg/hkr.pdf

Measure for 24 volts AC to the base of the sequencer when a cooling demand is present. (Should not be present)

Post some pics of your diagram and the sequencers that you have installed.


Photo and image hosting, free photo galleries, photo editing
 
  #3  
Old 07-20-14, 02:10 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,373
Received 10 Votes on 8 Posts
High voltage is always present at sequencers, even when a heat demand is not present. Be careful.

It is always safer to pay someone else to stick their hands in an air handler.
 
  #4  
Old 07-21-14, 08:13 AM
Member
Thread Starter
Join Date: Jul 2014
Location: USA
Posts: 3
Received 0 Votes on 0 Posts
Thanks for the response Houston!

I tested where you said and 24v were definitely present.
So I was wondering to myself why there would be a call for emergency heat when its set to cool? For the hell of it I thought I'd look at the thermostat, which seems to be functioning just fine. When I pulled it apart to look at the circuit board, sure enough there is a black scorched area (picture attached). I'm going to replace it today and see if it makes a difference. [ATTACH=CONFIG]35075[/ATTACH]
 
Attached Images  
  #5  
Old 07-21-14, 09:25 AM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,373
Received 10 Votes on 8 Posts
Remember to turn off power to the indoor unit before replacing the thermostat.
 
  #6  
Old 07-21-14, 09:44 AM
Member
Thread Starter
Join Date: Jul 2014
Location: USA
Posts: 3
Received 0 Votes on 0 Posts
So I replaced the thermostat and things seem to be working fine!! I'll post again if it cycles back into emergency heat, otherwise this may be a fix.

Thanks Houston for the help and for the link to the heater kit parts page. The label on my panel was unreadable, but from the pictures I figured its model HKR-20C.

One more question: When I swapped out the sequencers in the first place with a different model and slightly different specs, it didn't seem to make a difference. In your opinion, does it really matter? I mean whether they are open from 1-20 verses 1-30 etc. (can't recall the exact timing)?
 
  #7  
Old 07-21-14, 11:26 AM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,373
Received 10 Votes on 8 Posts
Of course the correct answer is always go back with the exact replacement but my main concern is that the heat strips are never energized without the fan because of different timing.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


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