Atwood water heater won't stay on.

When ours did that, it was the circuit board

"After shut down for about 10-15 minutes the WH ignites again, the red light does NOT come on, runs for about a minute or so then shuts down again. This is a gas only WH, no electric."


One of 2 things
Spark electrode is also used as flame proving signal return
Electrode soot/carbon will impede the milliamp flame signal that circuit board must sense or it drops DC to gas valve
Clean tip using emery cloth

Circuit Board.......valve track on circuit board is failing

Contact Atwood (Dometic) and inquire as to getting a new board...they have had some issues and replace them for free.

A guy came to me once with that kind of problem once. I asked him if he had filled the water heater tank with water. He disappeared, for a couple of minutes then came back and turned water heater on, all worked fine then.

Dusty R wrote:
A guy came to me once with that kind of problem once. I asked him if he had filled the water heater tank with water. He disappeared, for a couple of minutes then came back and turned water heater on, all worked fine then.

'trailrider' asked that question back on Pg 1 9/12/2020 and no direct answer.
"The obvious question is: "Is the water heater full of water?"

I have a problem very much like what Paul1944 describes...

-- New Atwood Gas G6C-8E-SP water heater in my RV
-- When Remote Switch is switched on, light turns red, then off within 10 seconds usually
-- Water heater stays on for 10 to 30 minutes, then turns off
-- The Remote Switch light does NOT turn back on
-- I cannot turn light off and then back on for an hour or two
-- After the shutdown, the sink running water is definitely warmer for 10-15 seconds so I know the heater has heated water. I assume that means there is water in the tank.

-- I installed a new RV Water Heater Thermal Cut Off Switch Kit Replace for Atwood 93866 - understood that it probably wouldn't make a difference but installed it anyway. It doesn't appear to break after cutoff and water heater can restart sometime later (like an hour or two later)
-- I purchased a new Atwood 91447 Thermostat Assembly and can install it if that would make for a difference

Old-Biscuit wrote:

"Model is GC6A-8E
Flame is more orange than blue.
There is a wire with what looks like a resistor in it, what is that for?"

8E has separate controls for electric & gas
ELECTRIC:
120VAC comes from a Circuit Breaker to on/off switch (backside of WH Tank) then thru set of T-stats to element (also backside of WH Tank)

GAS:
12VDC comes from Fused source to 'thermal cut out' (fuse in clear tubing----it blows at 190*F if flame blowback occurs and stops ALL DC to water heater. One shot device --replace if bad)
From thermal fuse DC goes to/thru TT-stat then to circuit board
Circuit Board then sends DC to ECO/Gas Valve AND spark electrode

From Old-Biscuit earlier comments, I take it that I should pay anything to the follow... Anything else?

=============
Posted earlier by Old-Biscuit
When flame lights off......is flame BLUE and quiet (very slight roar)?
IF NO (YOU stated more ORANGE then Blue)
Might need to adjust air shutter ---typically only needs to be roughly 1/4 open
Might need to clean orifice (soak in alcohol/air dry), clean burner tube (small bottle brush)
=============

So did the OP fix the problem?

You have a low temp thermostat and high temp thermostat on the water heater. If you got five minutes run time on propane, that might have been enough to heat the water to a point the high temp thermostat shut it down. They don't cost much. I paid 20.00 or so for both I think. They are screwed into the tank you can see them and the wiring through the service door.
First get the manual if it has the info, we found it not very helpful, and service or help line did not work. I talked to a Tech who does a whole lot of work every day on RVs and he changed them for me.
Also check your manual. Our Atwood 05 model will operate with both electric and propane on. The next year it was either or. I think they changed it back.
You didn't mention, or did I miss the on off switch led lighting up indicating a fault in all this.Without being there I can't figure it out for certain.
A good Mobile Tech cost but he'll have it repaired in no time. Water
Heaters are a frequent demand for them.
Also our manual mentions some models have adjustable thermostats but ours didn't have it and I don't know if new ones do or not.
Also the red light ours is orange does not come on unless there is a fault even when first starting the water heater.
An check that tube again. You may have pieces of dirt dauber nest you knocked loose in there and not out of the tube.

After it runs for a while and goes out, does it reignite by itself or do you reset the switch? Flame rectification is touchy and everything in the circuit has to be kept really clean. The ignition module gets a micro amp signal, through the ignitor, when the flame is present. The flame actually is part of the circuit and conducts the signal. The igniter rod and porcelain insulator needs to be clean. Wipe off the igniter rod insulator with a CLEAN cloth and alcohol and check it very very closely for any carbon tracking. Clean the igniter rod tip with Scotch-Brite pad or really fine sand cloth. Replace the igniter rod, if in doubt. They are cheap. Primary air adjustment is important and that’s why the flame should not be roaring or lifting because of too much air. If the flame lifts off the burner Or loses contact with the flame rod, the rectification circuit is broken and the gas valve will shut down immediately. Even the ratio of flame contact area between the burner and the flame rod is important. Make sure the end of the burner where the flame contacts it, is also corrosion free. The ground path from the burner to the module is also part of the rectification circuit so I added a copper ground wire between the burner and the module ground point and I used Deox on all the rectification circuit connections.
That covers almost all of the rectification issues and if you do all of these things, you shouldn’t have a problem with the flame rectification signal. Craig

trailrider wrote:
So did the OP fix the problem?

Don't you love it when an original poster doesn't update a thread with what fixed the problem?