Coleman Evcon Model # DGAT070BDD

[Pippi]

Well here is the skinny;  I turn up the thermostat and the furnace kicks on and runs for a short time then shuts down.  After doing this several time it will run for a longer time and bring the temperature up.  I have reset the thermostat, removed it and cleaned the connection points, etc. 

This A.M. I kicked up the thermostat and the same thing happened, so I pulled off the panels and noticed there was a flashing green light in a small box on the left side of the furnace (behind the panels) there is an on off switch so I pushed it off and back on.  The furnace began to run and continued to run till the temp reached the correct temp. (With the panels off) 

OK now it reached the temp 65 F  I set it on and kicked off,  So I kicked up the thermostat to 68 F. and it kicks on, runs, turns off kicks on runs and turns off (still with the panels off)  So the panels off doesn't make a difference.  (Just checking to see if there is enough fresh air coming in,  I just changed filters to a allergy type and was wondering if that could be the problem.)

Back to square one. 

Could this be as simple as needing a replacement thermostat?

Help!  And Thanxs for the help!  Pippi

 

[dkpd1581]

Trying to find an I.O.M. to help out with your problewm, I ran into a slew of recall notices for the model number you provided.  Below is the link, first check to see if your unit is affected.

http://www.cpsc.gov/cpscpub/prerel/prhtml05/05047.html

[Pippi]

OMG,  Thanks for the heads up on the furnace,  I went to the web site and yes it is one of the furnaces,  and I followed up with the find a service center,  There is one in a near by community.  The problem is it is quite cold right now, single digits and below.  We will just have to run our electric heaters to backup.   Thanks ever so much for the info.  I will give someone a jingle tomorrow.                                        

Pip

[Pippi]

Ok they are going to send someone out to install the recall kit,  but the problem with the on again and off again does not have anything to do with the recall issue. 

Could it be a thermostat issue?  Again I turn up the thermostat the furnace kicks on, runs for a brief time, shuts off, kicks on runs for a brief time, shuts off,  ect.  Then sometimes it kicks on and runs just fine???  

Thanks Pippi

[dkpd1581]

Look towards the over temperature safety switches.  It could be that your heat exchanger is heating up to the point where they begin to trip before the time delay engages the indoor fan.

The safety switches trip, then the fan comes on and cools the safeties and the exchanger.  They then close and allow the gas valve to engage and start the heating cycle over again.

Units can vascillate back and forth until the combinations of heat exchanger temp, safety switch status, and indoor fan delay all come together in the proper sequence.  Find what brings the fan on after the exchanger warms up (board timer, combination fan cycle/limit switch).

One way to prove it is the fan delay/timer is to turn the FAN from "AUTO" to "ON".  Once the fan comes on and runs, turn the heat on.  Then fan is already running and the exchanger  cannot overheat.  If the gas stays on and furnace runs normally (none of the cutting on and off you are seeing)  then it is what I described above.

If the problem still continues despite doing what is described above, you may have defective or weak safeties.  Safeties are typically bimetal devices whose characteristics can change over time due to age and repeated exposure to heat.

[knix]

I first want to say I LOVE THIS SITE.  But in trying to figure out my heater issue I stumbled on a site that is just for MH repair and specialized parts for us. 

I am going to link the website in the second post, so if you dont see a second post you/and I will know that it is against the policy of this site to link other sites, which if thats the case I am sorry and I dont want to offend the Samuria.

 

thanks Knix

[knix]

http://mobilehomerepair.com/

[hvacdrd]

Not a problem referring to any site here, the more information the better.

As to the original problem if the heat exchanger upgrade was not the issue then count the number of flashes the green light makes when it does not work. On the cover of the control panel there is a diagnostic chart that will tell you what the control is doing. Such as..1 Flash = Ignition Lockout...2 Flashes = Pressure switch Open...3 Flashes = Pressure switch stuck closed...4 Flashes = Open Limit

I suspect you will have a 1 Flash which means the control is not sensing the flame

Let us know...