Atwood water heater malfunctions

[daireemt]

We have a 7 year old, 6 gal. Atwood water heater (Model GC6AA) It is terribly inconsistent in igniting. R.V. dealer techs have adjusted it, more than once, our propane dealer, (a lifetime-of-knowledge-propane guy)has checked and adjusted it (twice) and it remains a problem. We never know if it will light and stay lit. May light on 1st attempt or may try 3 times and quit. May stay lit for several days, or may only work for an hour or so. Escept for a 10 day period last year when it worked from 200 feet below sea level @ Death Valley to 9,000 feet altitude @ the Grand Canyon North Rim, it has been a problem. Wind, outside temps, elevation, weather, etc, nothing has a consistent effect on it. We're tired of the suspense (and lukewarm water.) Any suggestions, or similar experience; or is this just a poor model WH? What say you?

[daireemt]

Thanks Clay & Brian,
My list of things to check out continues to grow. Never realized how many things have to work right to keep it lit.
Thanks Again , All

[BrianinMichigan]

So it's sparking alright? Also if it is a single wire tip for the sensor did you try a fine sandpaper on the sensor. ( 600 grit )Sometimes they can get a little carboned up and give a person fits.

[Clay_L]

Note that the electrode acts both as an igniter and flame detector. There is no thermocouple on your heater. The dealer was probably talking about the igniter.

Doug's suggestion to replace it is good. We had to replace one on my next site over neighbor's unit last year and we had to get it out in the light to finally see the crack.
Even in the desert you can get some dew and I think that was what caused the igniter to fail every so often.

[daireemt]

Thanks dougrainer, Pretty sure that electrode has never been replaced. I'll add it to my list of things to do. I'm bringing it in to the propane dealer next week & we'll go over the list I accumulated here. Our propane guy is more knowledgable than the RV dealer techs and more open to 'outside' opinions.
Many thanks, gents! I'll try and update as to what we find amiss.

[dougrainer]

The usual thing to do is
1. remove the orifice from the gas valve and clean it out. Debris floating around inside can cause intermittant lighting
2. REPLACE the Spark Electrode. Any hairline (unseen) crack in the porcelain white housing can cause spark and return flame voltage issues. Doug

[daireemt]

Thanks westend & 1fastdad! The RV dealer cleaned the electric connections as did I awhile back, so we're reasonably sure they're O.K. The propane dealer checked out the thermocouple & said it need'nt be replaced. One thing I forgot to mention, outside wind doesn't seem to have much effect on it. Sometimes it lights better with the access door open, but not always! Last week it stayed working through some pretty good winds- yet went out a day later while it was calm. That's why this this thing's making us crazy. I'll mention the gas valve to our propane supplier and see what can be done with it.
Thanks Again.

[1fastdad]

The first thing on the trouble shooting list is low voltage. Have you checked and cleaned all connections.

[westend]

Have you replaced any of the parts, gas valve, orfice tube and tip, thermocouple, etc.?
I've had a few cranky pilot lit appliances over the years and it mostly came down to delivery or exterior wind as the culprit. A faulty thermocouple was the cause of one failure. Wind can be eliminated by better shielding so that the pilot light isn't in a location where direct flow from the outside doesn't effect it. Delivery issues are harder to fix, especially now a days where there are no after market parts for the smaller gas valves. Whole replacement of the valve is the solution. I would assume that the dealer has cleaned and inspected the gas tube so that can be ruled out. If I had to make a guess from way over here, I'd be looking at the gas valve as the primary suspect.