We have a 6-gallon Atwood water heater which runs on electric and gas.I went outside early this morning and noticed water dripping out of our water heater outside compartment. The DSI fault light was lit (small indicator light adjacent to the on/off wall switch in our motorhome) I initially thought it was just a loose drain plug but when I opened the door to the unit outside there was no water dripping from the plug.I didn't have time to trace the source at that moment so I am not sure where the water was dripping from.Also, we noticed the water coming from the water heater at this time was extremely hot.....much hotter than normal.I turned the on/off switch off and let it set for several hours.I turned the water heater back on (electric) fifteen minutes ago and the DSI fault light has not come back on and there is no water dripping from the water heater outside compartment.Any idea what is going (what went) on?

Thermostat stuck and high limit switch lights fault code and turns off heater. Pressure relief valve opens because of increased pressure. This what the system is designed to do if the water is heated too much. You should find out what part of the system is causing the over-heating condition.

thermostat is not making good contact causing it to overheat and shut down on gas…

Since you did find the water heater really hot it is probably a stuck thermostat.. However The relief valve on the outside of mine sometimes will drip water and I have to pull the spring loaded lever a quick pull to make it stop sometimes. Just be careful doing this if it has HOT WATER in it as it will spew out.

Hi,RV water heaters are intended to have an air pocket at the top. Over time the air gets absorbed into the water. To reestablish the air pocket, turn off the pump, or disconnect from shore water, let the heater cool, then drain some water out.

I might add we have had the DSI fault light come on a few times over the past couple months. We would just leave the water heater off for a few hours and then turn it back on and everything would run fine.....until the next time it happened.Does this indicate a failing thermostat?We didn't notice if the water was any hotter at these previous times. We didn't notice if there was water dripping out at these previous times either.If the thermostat is stuck or not making good contact would replacing it fix the issue?

Atwood Water Heater | Good Sam Community

JJBIRISH
Explorer
Mar 15, 2014
tip: just clean the wire connectors and it might never happen again…
Old-Biscuit
Explorer III
Mar 15, 2014
Only thing it will hurt......

Possible Overheating
PRV lifting or constant dripping due to the overheating
No electric or propane should t-stat completely fail due to same set for both electric & propane operation
Relying on just the ECO to operate properly...if it should also fail then there is nothing to shut down heating source turning WH into mini steam bomb

Other than that.......nothing to worry about.

I operated commercial boilers for a living and there are redundant controls/safety features for a reason (dual t-stats, flame cut out, flame proofing, PRV)
BarneyS
Explorer III
Mar 14, 2014
I would just turn it off and on as needed. Shouldn't hurt a thing.
Barney
golfknut
Explorer
Mar 14, 2014
Thanks for all the responses.
You guys are great, a wealth of information at my fingertips.

The burner tube is clean and the flame is good.

I had a rv mobile tech out to diagnose a fault light issue 2 months ago but he couldn't find anything wrong with it. My guess is it wasn't acting up while he worked on it, if that's possible.

Is there any danger/downside to babying it until we return north from Florida in a couple weeks before replacing the thermostats?
BarneyS
Explorer III
Mar 13, 2014
golfknut wrote:
I might add we have had the DSI fault light come on a few times over the past couple months.
We would just leave the water heater off for a few hours and then turn it back on and everything would run fine.....until the next time it happened.

Does this indicate a failing thermostat?
We didn't notice if the water was any hotter at these previous times. We didn't notice if there was water dripping out at these previous times either.

If the thermostat is stuck or not making good contact would replacing it fix the issue?

Yes, it is a failing thermostat. I just went through this with my rig. Replacement is cheap (less than $15) and it is a simple matter of pulling off a few wires, peeling off the sticky foam covering, and putting the new ones back on. I got mine from Amazon.com. Just google your water heater model and thermostat and you will find the correct one. They come in a blister pack and there are two of them. You should replace both.

Edit: Here is probably the one you need.
Atwood 6 gal WH thermostats
Barney
Chris_Bryant
Explorer II
Mar 13, 2014
Old-Biscuit wrote:

...
Pry/bend three tabs out
Remove t-stat
...

I agree with all but this- the tabs should not be bent- they will only bend so many times, before they break. There is a slot in the hold down washer to go over the tabs. You just rotate it and slip the washer under the tab.
pianotuna
Nomad III
Mar 13, 2014
Hi,

Cleaning depends on use and location. I try mine on propane once a year--so it doesn't need cleaning. Insects can and do set up house in the burner tubes.
AStinker-
Explorer
Mar 13, 2014
Don't want to hijack the thread but I for one didn't know you could or were supposed to clean the water heater burner. pianotuna do you have a suggestion on how often one should clean the burner?
pianotuna
Nomad III
Mar 13, 2014
Hi,

How long since you cleaned the burner?

golfknut wrote:
I might add we have had the DSI fault light come on a few times over the past couple months.
We would just leave the water heater off for a few hours and then turn it back on and everything would run fine.....until the next time it happened.

Does this indicate a failing thermostat?
We didn't notice if the water was any hotter at these previous times. We didn't notice if there was water dripping out at these previous times either.

If the thermostat is stuck or not making good contact would replacing it fix the issue?
Old-Biscuit
Explorer III
Mar 13, 2014
Fault light......
Comes on if propane fails to ignite
OR
If ECO T-stat (High temp t-stat--energy cutout) operates (OPENS) whether on propane OR electric (OPENS at 180*F)

Your 'Normal' T-stat is not controlling. It has either failed or is not making good clean contact with WH Tank. (OPENS at 140*F)

The water dripping is from the PRV (Pressure/temperature Relief Valve) due to the very HOT water (OPENS at 210*F or 150 PSI)

Buy new set of T-stats----come as a set ECO/Normal
Replace them. Clean WH tank wall prior to installing new set.
Disconnect wires from t-stats (small lugs go on normal *Brown* large lugs go on ECO *RED*)
Remove foam cover
Pry/bend three tabs out
Remove t-stat
Clean up tank
Install new t-stat....press plastic washer down compressing spring
Secure with the three tabs (Bend them down---then tap them so t-stat is tight to tank)

Repeat for other t-stat
Install new foam cover
Hook up wires

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