Ignitor lights and then goes out(3X), ignition failure

[diddles]

Hi Guys!

Model # is DGAT070BDD, I'm trying to save money and just buy the part from you and fix my furnace myself.

I just replaced my burner assembly(ignitor, flame censor, etc.) to try and remedy my situation, the people we bought the mobile home from bought it and didn't get around to installing it. I got one flash(ignition problem) before and after installing this assembly package. Is it the gas valve? When the furnace comes on the ignitor lights, the flame comes on for 1 second(blue) and then shuts off, it does this three times and then shuts down completely. If it is the gas valve which one of yours is compatible? The gas valve I have now has a screw-on metal part that attaches to the bracket(which looks like the bracket you have for sale). I don't see how the 7990-328P gas valve, which other sites say is the compatible model, can attach in the same way... I'm heating with little space heaters right now so if I can figure out what part to get and hopefully you offer expedited shipping so I can get my furnace up and running again. Thank you in advance for your help

shelby
shelbygmoffett(at yahoo dot com)

[Robert]

Hi,

Gas Valve # 025 - 43627 - 000 can be seen and ordered through PayPal from this page:

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


May also need Mounting Bracket # 373 - 19801 - 063 .



Thanks,
Robert

[diddles]

Hey Robert,

Thanks for the quick reply! So looking at the bracket you told me to get, it's a female threaded opening, is the orifice on the back of the gas valve you suggested a male threaded protrusion? I can't tell by the photo. The bracket says DGAA, my furnace is DGAT, does that make a difference? My current bracket has a male threaded protrusion. Just wanted to make sure I order the right part so I don't have to send it back to you if it doesn't fit or something... thanks so much for your help! Oh, and by your answer, you think it's definitely the gas valve right? Just making sure

all the best

[Robert]

Hi Shelby,

Manufacturers and repair people and homeowners make so many changes in equipment, without being there to see what you have, I can't say for sure.

The gas valve itself will need a male fitting to go into to it.


Your furnace parts list lists the gas valve I gave and also the mounting bracket as a possibility.


IF you take pics of what you have, Mark can then look at what he has in the store to see if it is compatible.


Ignition failure is usually the ignitor, remote sensor or the gas valve as most common.


You have already replaced the first two, so the gas valve would be a good possibility.

Again, without being there to see and test, I cannot say for sure.


The only sure answer to those two questions would require calling an hvac tech out to inspect and test.


Thanks,
Robert

[diddles]

Hi Robert, me again.

Finally had an HVAC guy out to look at the system. He verified that the gas valve is working fine and ignitor, flame sensor, etc. He then touches the Vent blower/booster assembly/motor at the bottom of this structure and says that it's "hotter than it should be" and claims this might be what's wrong, does that even sound right to you? With an ignition failure code flashing? I mean he says that this motor comes on but it doesn't sound like it's as "loud" as it should be and he said the circuit board is "doing all the things it should be" so he says he's ruled that out. He also said when I replace the Vent blower/booster assembly/motor that I should make sure it's sealed where it connects(connects using three screws and a square 8-shaped felt seal). I just don't understand how this blower assembly has anything to do with the furnace staying lit. It still goes through the steps, it turns on with click, ignitor gets red hot, blue flame shoots out of the gas valve mounting bracket into the furnace and then 2 seconds later(literally) it goes out and repeats this exact procedure three times until it shuts off completely. The big fan motor never even gets a chance to engage. No heat, nothing but frustration. Please help

Looks like it's your item #7990-6451 he's referring to...

thanks!

[Robert]

Hi Shelby,

The booster motor MUST run and reach correct rpm's for centrifugal switch to close or reach correct water column pressure for pressure switch to close (didn't look to see which yours has).

It then must run that way the entire cycle. IF it does not, nothing will ignite and there will be no heat at all.

SO, only way booster motor is at fault is IF it starts fine and then suddenly heats up and quits, everything would shut down.

However, it should give different diagnostic code for that.

IF it is not sealed good, probably that and it is getting dirt inside.

Remove, thoroughly clean motor and wheel and remount and seal good and try it again.

What steps did he use to determine the gas valve, ignitor and sensor were all good ?


Thanks,
Robert

[diddles]

Basically he said that the gas valve is working fine because it was lighting and shooting flames against the flame sensor and whatnot. He used an amp meter thing to make some diagnoses clamping it around certain wires and inserting the probes into places. The furnace starts fine then after the flame starts shooting into the furnace cavity to heat the air it shuts off after two seconds and starts the whole process over again... after the third try comes the one single flash for ignition failure. There is dust inside this booster motor assembly could that lead to an ignition failure? This guy gave me a bill for $90. for nothing and told me he can put a new furnace in for around $2000. Seriously.

[Robert]

Tell him to troubleshoot and find problem and repair or take a hike. I would be leaning toward the ignitor with the little info I have now.


Thanks,
Robert

[diddles]

You still think it may be the ignitor even though it has been replaced with a new one and both the old and new one are doing the same thing, heating up red and lighting the flame like I thought they were supposed to do? Seems weird to me, hmm, this sure is frustrating I sure appreciate your help... you must be a late bird too.

[Robert]

Hi,

Had forgotten you had replaced the burner assembly. With that done, should have been fairly simple for a knowledgeable hvac tech.


Ignitor will have to glow and hold for about 30 seconds.



Thanks,
Robert

[diddles]

Think maybe it could be the control board?

[Robert]

Hi,

I don't think or guess, I test and find the problem and replace only what is needed. With what you replaced, you will need a reputable hvac tech to properly test and find the real problem.


Too many variables to try DIY from here over the internet.


Find what is needed and then DIY the repair from there.



Thanks,
Robert