Rheem furnace inducer running with no call for heat?


  #1  
Old 09-02-16, 09:43 AM
D
Member
Thread Starter
Join Date: Oct 2007
Location: Ohio, USA
Posts: 46
Upvotes: 0
Received 0 Upvotes on 0 Posts
Rheem furnace inducer running with no call for heat?

So all the of the sudden my inducer fan is running while the AC is turned on. It randomly turns on and off with no call for heat.

I have disconnected the heat wire from the thermostat to see if it keeps coming on. I was told that is how to test the thermostat to see if it is causing this issue.

Before replacing the main control board (if the stat is not bad) is there anything else that should be checked?

My Furnace is a Rheem Criterion II

Thanks in advance.
 
  #2  
Old 09-02-16, 02:39 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 64,939
Received 3,951 Upvotes on 3,544 Posts
Remove the burner access door and post the full model number from the ID plate located on the side wall near the burner.

It may not be a board problem. Some units will run the inducer if any of the safeties open.
What is the main blower doing.... is it also running when the inducer runs ?
 
  #3  
Old 09-09-16, 07:31 AM
D
Member
Thread Starter
Join Date: Oct 2007
Location: Ohio, USA
Posts: 46
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks for the reply.

The model is: RGDG-07EAUER

As far as I can tell the main blower is not running when the inducer randomly turns on. I also have not heard it running at all since I disconnected the heat wire from the stat. Of course both could be happening I may just not hear it or be home at the time.
 
  #4  
Old 09-18-16, 07:35 AM
D
Member
Thread Starter
Join Date: Oct 2007
Location: Ohio, USA
Posts: 46
Upvotes: 0
Received 0 Upvotes on 0 Posts
Last night the inducer came on so it's not the thermostat. The blower also came on. I shut the thermostat off (was in ac mode) but the blower kept running. I had to take the access panel off the furnace to get it to shut off.
 
  #5  
Old 09-18-16, 01:09 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 64,939
Received 3,951 Upvotes on 3,544 Posts
Was the heat wire still disconnected from the stat when the inducer and blower came on ?
 
  #6  
Old 09-19-16, 05:36 AM
D
Member
Thread Starter
Join Date: Oct 2007
Location: Ohio, USA
Posts: 46
Upvotes: 0
Received 0 Upvotes on 0 Posts
Yes it was disconnected.

It came on again last night. Both the inducer and blower. This time the thermostat was completely disconnected (it is one that the base mounts to the wall with the wiring and connects when you snap the stat in) so it cannot possibly be the thermostat.

This may sound strange but I have noticed the same thing happening. It seems like every time we close up the windows in the house (most of them) for the night it happens. It could be that I just hear it when everything is quiet but i can't be sure. Just throwing that out there.

Thanks
 
  #7  
Old 09-19-16, 09:35 AM
user 10's Avatar
Member
Join Date: Mar 2004
Location: NA
Posts: 1,829
Received 57 Upvotes on 50 Posts
Check for an error code.

Could be a flame sensed with no call for heat error.
 
  #8  
Old 09-19-16, 09:57 AM
D
Member
Thread Starter
Join Date: Oct 2007
Location: Ohio, USA
Posts: 46
Upvotes: 0
Received 0 Upvotes on 0 Posts
no error code just 2 solid green lights. Of course I would have to tape down the door switch and see if it happens again so i could check the lights while it is happening. Last night when it happened I took the door off and held the switch in for a few min and it never came back on.

If that error code does happen what could be the cause?
 
  #9  
Old 09-19-16, 01:35 PM
user 10's Avatar
Member
Join Date: Mar 2004
Location: NA
Posts: 1,829
Received 57 Upvotes on 50 Posts
Check to see if there an error for that -> the chart should be with the schematic.

If you get that error you should pull the flame sensor and check the ceramic for cracks, check resistance between flame sensor connection to the board (may be a molex connection) and ground.

Could also be a bad board.

It's worth checking for proper voltage at the board, electronics can do some weird stuff.
 
  #10  
Old 09-19-16, 01:50 PM
D
Member
Thread Starter
Join Date: Oct 2007
Location: Ohio, USA
Posts: 46
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks for the reply. I will check the sensor when I get home to see if it's cracked....just to rule that out. Then wait to see if i get a code.
 
  #11  
Old 11-10-16, 05:41 AM
D
Member
Thread Starter
Join Date: Oct 2007
Location: Ohio, USA
Posts: 46
Upvotes: 0
Received 0 Upvotes on 0 Posts
Haven't updated this in a while because I thought I had it figured out.

I changed the stat thinking maybe it was the problem. It was older anyway. The reason was that as far as I could tell the inducer and blower only came on one time after I completely disconnected the stat.

IT seemed to be fine until I had to turn the furnace on for a period of time. This morning I could hear it short cycling. It would run for 5 min or so and shut off. Then 15 min or so later it would turn on. it did this 3 times and the last time the stat was reading the desired temp. After the 3rd time it only stayed off for a min or 2 then the inducer came on. I ran down to see what it would do. It never actually turned on the ignition. The inducer spun for a bit then it turned off.

Any clues here? With the short cycle happening I was thinking maybe the high limit switch was failing but would that explain the previous symptoms of the inducer running for no reason?
 
 

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