Atwood Flameout

LJS · 07-02-2008, 07:12 PM

I have an Atwood GCH10A-3E water heater in my 2000 Chieftain and I'm having problems when using it on LP (Works fine on AC).

After lighting the burner, it will usually burn normally and then you can hear the flame gradually decreasing, then increasing, and on some occasions it will go out. I have adjusted the flame numberous times, with no change in outcome.

On most occasions the igniter will relight the flame. However, on several occasions I have had to replace the Thermal Cut-off. After replacing it the heater will usually work ok for several trips, then the thermal cut-off will open and and shut the water heater down. Following this event the water heater will not light and I get no "Pilot Out" light on the display panel.

In seveal instances, prior to the thermal cut-off opening, the flame will actually flash back out the exhaust vent. The Atwood tech suggested this may be caused by bugs/spiders in the burner tube. I have examined both the burner tube and the exhaust tube and found no evidence of any bugs/spiders.

Any suggestions or help would be appreciated.

LJS

LJS · 07-02-2008, 07:12 PM

I have an Atwood GCH10A-3E water heater in my 2000 Chieftain and I'm having problems when using it on LP (Works fine on AC).

After lighting the burner, it will usually burn normally and then you can hear the flame gradually decreasing, then increasing, and on some occasions it will go out. I have adjusted the flame numberous times, with no change in outcome.

On most occasions the igniter will relight the flame. However, on several occasions I have had to replace the Thermal Cut-off. After replacing it the heater will usually work ok for several trips, then the thermal cut-off will open and and shut the water heater down. Following this event the water heater will not light and I get no "Pilot Out" light on the display panel.

In seveal instances, prior to the thermal cut-off opening, the flame will actually flash back out the exhaust vent. The Atwood tech suggested this may be caused by bugs/spiders in the burner tube. I have examined both the burner tube and the exhaust tube and found no evidence of any bugs/spiders.

Any suggestions or help would be appreciated.

LJS

AFChap · 07-02-2008, 07:34 PM

When I had a severe flashback due to a spider web in my burner tube, I had to totally remove the tube from the WH in order to see/find it. But it does sound to me like your problem more likely is due to poor air flow.

Many of us have had to make alterations in order to increase air flow behind the inner metal door. I cut apx 1" notches on both side lips of the inner metal door toward the bottom half, flexed/bent the door a bit to open the bottom more, and removed rubber gaskets from the bottom inside of the metal door AND the bottom inside of the outside fiberglass door. That seems to have cured the tendency to eat several thermal cutoffs a year.

Rick Long · 07-02-2008, 07:35 PM

If you keep blowing thermal cutoff's you need to replace the thermostat and possibly the ECO which is right next to it. You might think about getting the adjustable thermostat. CW about $30. They also carry the regular thermostat.

Clay L · 07-03-2008, 07:22 AM

I had problems with my Atwood requiring several ignition attempts and it making a loud roaring stuttering noise.
I couldn't see into the tube very well because of the bend. I took a piece of foam pipe insulation and pushed it through and back and forth in the tube to clean it. Dirt dauber nests would take something stiffer I would think.

I found nothing in the tube and the problem with mine turned out to be involved with the centering of the burner assembly.
I saw a post concerning this quite a while ago and don't remember where I saw it.

In any case after I took the whole thing apart and put it back together with everything centered, it worked fine and has continued to work for three years.

Warpath · 07-03-2008, 08:22 AM

I also have a possessed Atwood water heater that I have been fighting various issues for 2 1/2 years. But one of the biggies has been the strong flame which slowly fades and than goes out.

I am excited to try your suggestion Clay L. If that doesn't work it's getting the sledge hammer

AFChap · 07-03-2008, 10:06 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">If you keep blowing thermal cutoff's you need to replace the thermostat and possibly the ECO which is right next to it </div></BLOCKQUOTE>
Not necessarily, Rick. You're on the Winnebago forum here and this is a known problem on Winnebago coaches (I see from your sig that you have a non-Winnebago coach). Winnebago blames Atwood, and Atwood blames Winnebago. In reading the rationale I can't buy Atwood's reasoning. Newer Winnebago coaches have a vent hole in the outer WH door as part of the solution. There is a Winnebago service bulletin on the problem, and special rubber "door bumpers" created to resolve the air flow problem. But the door bumpers would not work at all on my coach as with them in place the outer door would not latch. In looking at what the bumpers were supoosed to do I found removing the rubber seal at the bottom did the job better than the bumpers would have.

Duner · 07-03-2008, 11:57 AM

LJS, your gas regulator may be going boonkers and giving you low or changing pressure. Does your gas furnance work ok? Try turning on all the burners on your stove. Does that affect the flame in the water heater? Does the burner flame stay the same level as you turn on the next burner, and the next burner? You can try this just to eliminate the regulator as a possible cause.

Ding-a-ling · 07-03-2008, 01:05 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Warpath:
...one of the biggies has been the strong flame which slowly fades and than goes out. </div></BLOCKQUOTE>

Sounds like the typical Winnie trouble of inadequate air supply that Paul refered to.

Last winter I had the same scenario - good strong flame that died out. I took the easy way out.

Instead of cutting a hole in the access door or putting on bumpers, etc.

Just to experiment, I wedged a piece of clothespin under the pin-hinge of the inner door to make a little more air-gap.

The piece of clothespin is still there and the WH works fine on gas.

LJS · 07-03-2008, 03:24 PM

AFChap - Thanks for the suggestion regarding the alterations to the door. This is similar to a suggestion the Atwood rep also mentioned. I used an approx. 1" flexible hose with a small rag in front and pushed it through the exhaust tube to make sure it was clear. The burner tube I was able to visually inspect.

Clay L - Didn't think of making sure the burner assembly was centered-will check it.

Duner - I have wondered about the water heater regulator. All other gas appliance seems to work fine.

Ding-a-ling I like your idea! I'll give that a try before making big changes to the door.

Thanks to all!

LJS

SCVJeff · 07-03-2008, 03:48 PM

There are a bunch of posts on this in the forum, including mine. As far as I'm concerned, Atwood is clearly at fault. On my '06, Winne cut a vent slot in the door, but the Atwood door is still un-vented. I punched 4ea. 1" holes in the Atwood door across the Winne door slot, screened it, and my problem vanished.

LJS · 07-03-2008, 03:52 PM

SVCJeff - You're right! I just went out and did a search in the forum using "Atwood water heater" and got back a whole lot of results, some even had pictures. Definitely gives me a better idea of what I am dealing with.

One thing I don't understand is that I have had this coach for over 5 years and didn't have a problem until about 1 1/2 years ago??

LJS

SCVJeff · 07-03-2008, 11:53 PM

Beats the heck outta me! I took the coach to the dealer for the problem, they did the cheezy door bend (gimme a break!), pulled the foam insulation seal and gave it back. Before leaving I asked to see it work and of course it failed. While standing there I watched them remove parts from 2 different brand-new rigs, all with the same results.

I forget how the conversation with Atwood went, but I asked them if I would void the warranty if I fixed the door the way the factory should have. They said "no", so out came the punch's.

This apparent finger pointing between Atwood and Winne is stupid, and we're caught in the middle fixing it while the children squabble.

BTW- My burner is now so quiet that it's often hard to tell it's running.

DriVer · 07-04-2008, 07:09 AM

It is definitely an air supply problem because if I open and allow the water heater door to hang open I do not have any air supply issues and the flame burns normally. I did have to adjust the vent tube repeatedly and experiment with different settings since it didn't want to work at all until I found a sweet spot and settled on its current position.

A couple of years ago now WGO installed an extended length chimney which sticks out past the door about 1/2". The tech that worked on the heater at that time opened the vent wide open because it would seem that it was the best option at the time but the burner kept blowing out until I choked it back.

With my door closed the flame begins to burn and then it'll slowly diminish and pop-out. The igniter will click a few time and the burner will begin to burn. The funny part is that it doesn't always happen consistently in the same manner. Sometimes the flame will get a bit quieter but it'll keep burning.

At the end of the day the burner works well enough to keep the water hot with the door closed but with inconsistent burner action.

Before I adjusted the vent tube I was going through a lot of safety valves (diodes). Knock on wood I haven't replaced one in a few months.

"007" · 07-04-2008, 08:35 AM

Some people have added a extra vent in door to solve their problem.

traveler of california · 09-30-2008, 11:41 AM

In order to avoid buying these expensive fuses, I have been opening my doors and it seems to work fine - no lost fuses.

I notice that there is a "window" allowing one to view the flame and it is covered in plastic. Would removing this covering help? I'm just not sure about cutting notches, etc.

Nick
Journey '01

troth · 09-30-2008, 12:03 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> I notice that there is a "window" allowing one to view the flame and it is covered in plastic. </div></BLOCKQUOTE>

Yup! Pop out the round window; I did and it works much better!

Randy Chesnutt · 09-30-2008, 12:20 PM

On mine I removed that clear peace of plastic that you could look threw to see the flame and worked fine ever scent.

ChasA · 09-30-2008, 02:09 PM

I see several posts in this thread referring "inner door" and "outer door" My water heater has only one door. I have not seen any water heaters with 2 doors. Can someone educate me about where the inner door would be located? I've been having problems with my water heater on gas. It'll light and burn for about 5 seconds, then the gas solenoid clicks off and of course the flame goes out. It will repeat his 2 more times. Sometimes it stays lit after the third try, sometimes, it goes into lockout (Pilot off light illuminates). I then turn the switch off and retry and it eventually lights and stays lit. I have removed the burner and cleaned it and the flue to no avail. Having the door open makes no difference. I THINK that the spark ignitor is also a flame sensor and that it or the circuit board are at fault. Does anybody know for sure if the ignitor is also a sensor. Seems to me that a direct spark ignition system must have some means of sensing a flame so that it will shut down the gas if the flame goes out and the only thing in the flame is the ignitor. I would appreciate your insight.

AFChap · 09-30-2008, 04:04 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">"inner door" and "outer door" </div></BLOCKQUOTE>
ChasA

Most Winnebago coaches have a fiberglass or aluminum "outer" door over the water heater. In 007's pictures above, you are seeing what we are calling the "inner" door ...the metal door that is a part of the water heater itself. What you don't see in 007's pics is the "outer" door painted to match the side of his coach. The "outer" door lifts up like the baggage compartment doors while the "inner" door drops down.