Why is water heater is shutting off?

[Senior Chief]

We've got an Atwood G6A-8E (6 gal) gas-only water heater in our '89 Fleetwood.

Recently, its been shutting off at random, occasionally indicating a high-temperature lockout according to the manual (the indicator light comes on at the remote switch and stays on) and other times nothing, just the burner shutting off. It may run properly for a couple days,and then shut down several times in short order.

The circuit board was replaced by the previous owner just prior to us buying it. Not sure if this is a new condition or not, since previously we'd been turning the WH off after showering & dishes to conserve propane.

Any ideas?

Its annoying at this point, but not critical, but I'd sure like to figure this out.

[ga traveler]

There are a lot of electrical connections on the outside of the water heaters. Many times we simply unplugged all connections, cleaned the conn. and reattached. Remember there is a lot of moisture in this area. moisture and 12V many times equal corrosion.

[Senior Chief]

Thanks, I'll try just cleaning the connections and see if that works.

[BA-in-Mich]

check the connections on the gas valve itself. Pull them on and off a few times to clean them up. also look at the thermal cutoff switch which is on the side of the heater ( only 2 wires on it ) once the heater gets to around 140* it trips out till it cools down and then it resets itself. The connections might be a little corroded there also. Then there is the flame sensor that monitors the flame. Make sure when it does run that it is getting enough flame hitting it. Blow some compressed air in the flame tube could be some junk in it or where the heated come out of the heater.

[leadman]

Check the little door by the burner tube. Our had debris that had gotten in the vent screen and piled up on the tube and sensor. This corrected the issue we had with it not wanting to light at times.
Then we had the same issue as you with the overheat light coming on. I replaced the temp sensor and the other sensor on the pad at the top right of the unit. Cost was about $20 IIRC. This helped for awhile, then in Wyoming last fall I replaced the control box and this fixed it. This was about $180.

One thing to check is the water level in the water heater. I found that if you do not open the relief valve when the water system has pressure that there may be too much air in it and it goes in to the overheat condition and turns the light on.