Coleman model DGRT070AUA

Questions about repairs and parts for Coleman furnaces, air conditioners and heat pumps for manufactured homes. Click here for Coleman parts.

Moderators: Mark, Greg

Locked
Terry
Posts: 4
Joined: Mon Mar 02, 2009 10:49 am
Location: Alabama

Hello all, my gas furnace is a Coleman model # DGRT070AUA. It is in a 1993 mobile home. It seems like it takes too long for the blower to come on after the burner ignites. I have timed it and it takes anywhere from 3 1/2 minutes to 3 3/4 minutes from igniting until the blower comes on. Is this normal to have such a long preheat time?
User avatar
Robert
Moderator
Posts: 6413
Joined: Wed Feb 28, 2007 12:07 am
Location: Tennessee

Hi,

Most likely a bad Fan Switch # 7975-3281 which can be seen

and ordered through PayPal from left side of page here :

http://www.mobilehomerepair.com/ColemanGas.html



Thanks,
Robert
Some people are Humbly Grateful, while some are Grumbly Hateful.................... Which one are you ?
Terry
Posts: 4
Joined: Mon Mar 02, 2009 10:49 am
Location: Alabama

Thanks, Robert. I ordered the part today and I will give it a try when it comes in.

Thanks again,
Terry
User avatar
Robert
Moderator
Posts: 6413
Joined: Wed Feb 28, 2007 12:07 am
Location: Tennessee

Hi Terry,

You're very welcome, hope that takes care of it. Sometimes it doesn't, but most often that is the culprit.


Thanks,
Robert
Some people are Humbly Grateful, while some are Grumbly Hateful.................... Which one are you ?
Terry
Posts: 4
Joined: Mon Mar 02, 2009 10:49 am
Location: Alabama

I installed the new fan switch, but it didn't make a difference in how long the furnace preheated before the blower came on. It is still taking around 3 minutes and 45-50 seconds from the burner igniting and the blower coming on each time the thermostat calls for heat. I've even changed thermostats, but no difference. This furnace is a huge gas hog anyway, and I am sure that this long preheat time may have something to do with that. The thermostat is set at 62 daytime and 54 at night just to keep it from using tons of gas. The burner has been adjusted correctly, so I am at a loss on what is going on with this furnace.
User avatar
Robert
Moderator
Posts: 6413
Joined: Wed Feb 28, 2007 12:07 am
Location: Tennessee

Hi Terry,

The fan switch is only component that controls temp of when blower starts.

So, if it takes that long, then the problem lies in fact that burner is not hot enough and takes too long to heat chamber to blower on temp.


Check burner and burner orifice both for blockages (spider/web).

IF all ok, need to have gas pressure and firing rate tested and furnace chamber inspected to diagnose why there is a prolonged heat up time.


Fan Switch could be faulty, rare, but it does happen. However, with no change, I would suspect above suggestions.


Thanks,
Robert
Some people are Humbly Grateful, while some are Grumbly Hateful.................... Which one are you ?
Locked