Water heater glitch

[Jhcowdude]

Atwood G6A7 water heater lights fine. Heats water to temp, then shuts off as it should. Use the water and it won't relight.  It's an auto starter, lights fine when you flip the switch.  Replaced the thermostats, they were pretty dirty and just needed replaced. Wires all checked as they should. I guess the next step is a new circuit board? I cleaned contacts as well as I could, but they look fine.  I am open to ideas. Thanks!

 

[Gary RV_Wizard]

According to the Atwood service manual, the G6A-7 is a pilot light model, not DSI.  It could be pilot-only or pilot-relight, but in either case the heater should fire up the gas burner on demand.  So yours has a pilot light, right?


Dirty thermostats?  Meaning the wire connections or ???  It's just a contact device and external to everything, so how does it get dirty?

Does the heater attempt to re-light and fail, or make no attempt at all?
Will yours re-light immediately if you flip the switch off and then on again? Or does it have to cool down first.

I fixed one for a friend that acted like yours and it was indeed the circuit board. Apparently something inside the potted board opened up when it got warm.  His could not be re-lit until the tank cooled down. 

 

[Jhcowdude]

That's the model number on the sticker, but possible it's been swapped and sticker wasn't. It definitely doesn't have a pilot light.  Thermostats just had 20 years of crud, and an easy replace. Contacts are now clean and tight. It will relight by the switch, just not automatically. It makes no attempt to relight. Fiddling with circuit board connections again, got it to work properly once. Maybe I didn't do a good cleaning job on it before. Gonna keep messing with it. Will update!