Water heater inoperative

[sumrfun45]

Have 1997 Winnie Brave 31RQ.  One year old Dometic model G6A-8E-SP no longer ignites.  Worked fine until last couple days of our trip.  First the water heater stopped mid-cycle of heating the water.  Re-started and it lit and then went out within a couple seconds.  Tried several more times unsuccessfully, although the igniter continued to work.  Then after several more tries, the igniter no longer sparked and therefore no combustion at all.  Pulled the various terminals off looking for any possible corrosion, etc.  Still same results.  Next I had my wife hit the water heater start switch while I used a long starter lighter to ignite it.  It would ignite the propane, but within a second or two, the flame would go out.  Flame looked perfect color, etc, but no dice.  No heat.  Have plenty of propane, etc.  Looked for any loose wires, etc.  Nothing.  I'm stumped because the situation went from one problem (not staying lit), to second problem, (no igniter spark).  Thanks for any help. 

[bm02tj]

The burner safety is not seeing the flame 

bad ground dirty flame rod ignitor 

 

[manholt]

IMHO, you have a bad ground.

 

[kaypsmith]

8 hours ago, bm02tj said:

The burner safety is not seeing the flame 

bad ground dirty flame rod ignitor 

 

Or bad thermistor. Or stopped up flue, make sure there is no wasp or mud dauber nest in the flue.

Edited July 19, 2020 by kaypsmith

[sumrfun45]

 OK all you fine RVers........here's what I've done.  Pulled the igniter and cleaned it, reinstalled.  Checked all grounds....all are good.  Cleaned ECO and Hi-Lo temp sensors & reinstalled.  Checked continuity of thermal cut-off fuse.....OK.  Cleaned burner tube......was spotless. 

To reiterate, water heater is in the second month of it's second season.  It's essentially new and clean as a whistle.  The scenario is......worked fine for first few days of trip.  Then turned on one morning and it started and ran for about 10-15 minutes and just shut down.  When I noticed, I switched it back on and the igniter worked and lit the gas, but immediately shut off.  Tried it another few times and then the igniter stopped sparking.  I then had my wife turn the switch on and I lit the burner tube with a long lighter.  It would light and then go out within a second or two.  So now I'm left with a water heater that won't even spark.  (Probably been started 30 times or less since it was installed last year.)  I've been RVing for 31 years, so I'm fairly familiar with the routine mechanical issues of keeping an older RV going.  But this one has me stumped and I'm appreciating your feedback.  Does anyone suspect the circuit board?  Seems like it's the only component I've haven't been able to check.  Shouldn't the signal for the spark to the igniter be sent from that board?

[bm02tj]

If you have covered all the other parts and that is all that is left 

Part of the ground is  burner to electrode so it can see the flame as a small current needs to pass through the flame 

[kaypsmith]

When was the last time that you changed LP cylinders? I had a similar happening two years ago, the propane station overfilled the tank, not enough room left in tank to vaporize, also a bad regulator will behave the same way. I know this doesn't explain the igniter failing, that is probably another issue. Have you checked other gas appliances to make sure they are working correctly?

Edited July 20, 2020 by kaypsmith

[sumrfun45]

Quote

Yes, the tank is 1/2 full and I've started the heating unit and the stove/oven all work fine. 

 

[ianbullock]

Are you saying that the water heater is new? Only one year old? If so Dometic water heaters all have a 2 year warranty.

If I were you I would take your Brave to a dealer and get fixed under warranty right away.

[kaypsmith]

The thermocouple is probably bad or misaligned, with all the trouble shooting you have done. As Ian said, I would sure try the warranty route. Although a new thermocouple should be less than $30.00.

[urbanhermit]

Wondering about grounding, which was the first two responses.  The symptoms don't seem to me to involve gas supply, esp. with the failed igniter.  Could there be a "the other end" of a ground wire away from the water heater, not visible behind the heater access door?

[rayin]

Outcome?

[manholt]

UH, yea...the circuit board & it's located behind heather.

[dickandlois]

On 8/14/2020 at 7:17 AM, UrbanHermit said:

Wondering about grounding, which was the first two responses.  The symptoms don't seem to me to involve gas supply, esp. with the failed igniter.  Could there be a "the other end" of a ground wire away from the water heater, not visible behind the heater access door?

Our unit quit a day after working just fine. I cleaned the control board contacts, both the male and female pines with some DeOyx spray / then used a Drummel tool and a soft wire brush. Fallowed with a very light coating of conductive grease. One used in the electronics industry.   A little pricey and not found at automotive outlets. Some of the replacement boards are made by a universal replacement supplier. These tend to have an adapter to be able to mate up with the OEM wiring.

Had cleaned and checked the ground connections about 2 years earlier.

Rich.