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View Full Version : Criterion Gas Furnace Draft Inducer Motor runs continuously.


Bobinorlfl
Nov 22, 2012, 09:05 AM
The draft inducer motor runs continuously. Thermostat set to off, inducer still runs. Heat and AC functions still operate normally but system never "shuts-down" after heat turns off. (Inducer motor runs during AC operation as well.) I suspect either the pressure switch or inducer motor relay are not releasing as they should. I saw a reference to condensate as a possible cause but not sure if there is any real connection there (You Tube video on inducer motors made quick comment that condensate could cause problem? ). Suggestions welcome...

PJmax
Nov 22, 2012, 07:01 PM
It's not the pressure switch. It probably is the inducer fan relay.

Pretty strange though... the control board should see that since the inducer is running that the draft proving (pressure) switch is showing closed before it should be. This is done on purpose so that you can not defeat or bypass a pressure switch issue.

The long and short of the problem here is that you are probably going to need a new control module. I don't think the inducer relay is replaceable by itself.

With a make and model number we could probably go further.

Bobinorlfl
Nov 22, 2012, 09:14 PM
I suspect that you are right I just wanted to research a bit further to before buying a new IFC. It is Model # 1012-925A PN 62-24268-01 and is in a RGDJ-07EAUER Rheem Criterion Furnace. It seems that the Inducer Motor relay is probably hung-up in the always "on" position. I appreciate your input about not being able to replace the relay by itself -- I was considering that as a possible next move. I wish I had the schematic for the IDR instead of just a wiring diagram! Thanks...

PJmax
Nov 22, 2012, 10:15 PM
I'll check out your model number later. If you are electronically inclined you could change the relay itself. It's going to be soldered to a p.c. board. You would have to match the relay based on sight as the company will not support any info like that.

PJmax
Nov 22, 2012, 10:24 PM
This should be your board. Several relays on board. While I was looking at the board I came to think that it could also be a logic problem on the board. The board turns on the relay. The relay could actually be OK. A meter would be needed to check for relay status.

Bobinorlfl
Nov 23, 2012, 06:55 AM
This should be your board. Several relays on board. While I was looking at the board I came to think that it could also be a logic problem on the board. The board turns on the relay. The relay could actually be ok. A meter would be needed to check for relay status.
What type of logic problem do you think I might be encountering? My board is slightly different that the one you showed. I probably will have to study the circuit board and draw my own schematic of the exact relay so I can troubleshoot it.

PJmax
Nov 23, 2012, 09:19 AM
Trace out the foils from the inducer motor connection to the relay. One will most likely be a common neutral and the other should go to one contact on the relay. After you locate the correct relay on the board you'll need to use a meter to see if it's stuck closed. If the relay checks as normal then you may have a logic problem and there is no way to fix that. The logic is programmed on a chip and can't be read or altered any more.

Bobinorlfl
Nov 23, 2012, 10:38 AM
Thanks for all your help! I'll post my findings after I am able to pull the board and do some more troubleshooting. I do appreciate your assistance!