Atwood Hot Water Heater Problem

[OREddie]

I have a model GC6AA-10E Atwood hot water heater installed in my 2017 Forest River 2401WS MBS (Sprinter). On a recent trip to British Columbia and Alaska the hot water temperature gradually went from hot to tepid to cold on both propane and shore power over a period of 48 hours.

I checked every fuse with a meter, checked the circuit breakers, continuity of thermal cutoff and other connections and all were good.

On return home the selling dealer's service department diagnosed a faulty circuit board. After waiting 3 weeks for them to get a new board and hearing nothing back I purchased one (never hurts to have a spare) that came in 3 days and installed it today. No change - still no propane or electric heat.

Any other thoughts about what might be wrong? Could the valve be defective? Even if it were, shouldn't the electric end work?

Thanks in advance for any input!

Ed

[ejohnson1144]

Did you check the wire going to thermal disc thinking there is a crimped inline thermal fuse.

[ejohnson1144]

Originally Posted by ejohnson1144

Did you check the wire going to thermal disc thinking there is a crimped inline thermal fuse.

This little dudad

[Witch Doctor]

No, on the face of the wall there are two little disk, they are your limits for gas and electric, they are about as big as a dime and have two red wires to each. I don't know what you are showing.

[Witch Doctor]

Do you have a meter? It's weird that both sides went out. On the back side is your electric heating rod, make sure it's getting 110v. Also ohem it to see if it is broke

[Freetyme]

Does sound like some sort of thermal sensor that would call for heat be it gas or electric.

[KyDan]

Sounds a lot like a bypess valve that is not completely closed.

Also-- does the burner fire and stay lit for some time??
The electric heater is totally independent of the burner and board.
Even if the board is toast the electric side will still work assuming you are plugged into shore power.

Did you try pulling the handle on the "pop off valve"?? Be careful!! Is the water in the tank hot?? That would tell you.

[Bama Rambler]

One thing that bothers me is that you said that "the hot water temperature gradually went from hot to tepid to cold on both propane and shore power over a period of 48 hours." that sounds like the winterizing valve started leaking by, either by vibration, or leakage.

If the heating sources stopped it would be hot up to a point and then it would be cold.

Having said that, according to the manual, the only things that are common to both gas and electric are the +12 and -12v power to the control board and the control board itself.

Have you checked power at the remote panel switch?

[onetonford]

Since it is a atwood I found a wire diagram and looking at it could be a bad termostat or thermal cut off or no power to the 12v side of the board.

[ejohnson1144]

Make sure if you have outside shower , it is turned off.

[OREddie]

Originally Posted by ejohnson1144

Did you check the wire going to thermal disc thinking there is a crimped inline thermal fuse.

Thermal "disk" ?

[OREddie]

Originally Posted by ejohnson1144

Did you check the wire going to thermal disc thinking there is a crimped inline thermal fuse.

If you mean the thermal cutoff that's supposed to melt if flame gets to it from the burner tube, yes. I replaced it. I also removed it and plugged the line in without the thermal cutoff. No joy.

[OREddie]

Originally Posted by ejohnson1144

This little dudadAttachment 186397

Doesn't look the same as what I have but looks like it serves the same function. Replacing it didn't help. When I turn either electric or gas on nothing happens at the gas valve. Doesn't explain why electric doesn't work so I'm starting to think it may be at the new fangled digital display that controls water pump, slide outs, awning, hot water heater, etc.

[OREddie]

Originally Posted by Bama Rambler

One thing that bothers me is that you said that "the hot water temperature gradually went from hot to tepid to cold on both propane and shore power over a period of 48 hours." that sounds like the winterizing valve started leaking by, either by vibration, or leakage.

If the heating sources stopped it would be hot up to a point and then it would be cold.

Having said that, according to the manual, the only things that are common to both gas and electric are the +12 and -12v power to the control board and the control board itself.

Have you checked power at the remote panel switch?

You're right on. Obviously the system shut down completely but water slowly lost heat over time. The manual suggests checking over voltage (>14V) but I don't know where to test. The remote panel is digital and wiring behind looks like a pot of spaghetti that would feed an army; some fuses there I wasn't aware of as well. I'll open it entirely tomorrow as I think that's the right track to follow.

Thanks for the ideas.

[OREddie]

I'll take a few pictures tomorrow and post. Many thanks for all the ideas! It was the seller's maintenance tech that diagnosed bad board but I was suspicious of his logic. The replacement didn't do a thing.

[Witch Doctor]

Where you check for voltage is at the board, I think that wire diagram shows a orange wire, but I know mine are red going to the board on top of the 10 pin connector not at the switch. These boards are garbage and you could have gotten another bad new board. If you have 12 volts going to the board then trace the other wire from the board and make sure it's supplying 12 volt from the board. Check at the gas valve or the silinode. If you trace that red wire from the board it will go to the thermo disks first then to the valve if I remember right. Hope that helps...

Originally Posted by OREddie

You're right on. Obviously the system shut down completely but water slowly lost heat over time. The manual suggests checking over voltage (>14V) but I don't know where to test. The remote panel is digital and wiring behind looks like a pot of spaghetti that would feed an army; some fuses there I wasn't aware of as well. I'll open it entirely tomorrow as I think that's the right track to follow.

Thanks for the ideas.

[OREddie]

Here's a couple pictures of my system and work. Number 1 is my hot water heater as currently configured - new control board and thermal cutoff. If someone can point out the "disks" referred to in earlier posts I'd be much obliged.

Picture 2 is of the original control board I replaced and one of the two thermal cutoff devices I ordered, one of which I used with the replacement control board.

Thanks!

[ejohnson1144]

Underneath the foam black pad

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[ejohnson1144]

T stat eco on it

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[ejohnson1144]

If you jump out the two brown wires and it works it's a bad disc
If you jump red wires together and it works it's that disc

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