Atwood water heater usual nonsense.

[reeman]

Diagnosing sparking cycle issues. Firstly the control circuit board seems to work for electric properly and is heating to appx. 130f properly. However the propane warms to luke warm and cuts out on the three try signal fault and has done that since I bought the trailer. Someone had siliconed the heck out of the door to reduce wind problems while on propane so I removed that nonsense. It was not the issue. Then I discovered that some clown had opened up the venturi on the gas burner way beyond spec so I fixed that. No go same problem. Then I changed the sparker that uses resistance to determine whether or not there is flame, all with the right factory settings and not aftermarket trash. No go. Then I change both the thermostats and made sure they were contacting the tank bottle correctly and the cutoff fire sensing heat fuse wire was not causing the issues. No go. It still works if I keep turning the gas power switch off and on and I can get the water to about 110f by doing so on gas. The fault light is not coming on so there is no indication of a fault with anything that I did. The flame is nice and blue and consistent until the spark sensor does not tell the unit control circuit board that there is flame and the burner is actually going.

THEREFORE the fault is either a faulty circuit control board or worse a messed up electric gas valve control or both. The unit is 2016 so it is still available for now but like all parts on things who knows for how long. We certainly do not want to replace the unit completely as that would be stupid as it works perfectly on 120v and is fine other than flakey controls.

Does anybody here have experience that is similar with the 6 gallon Atwood/Dometic water heater? Could changing the expensive circuit board be the best option or do the electric gas controls cause issues with these units?
Almost makes me go out and get a manual unit that runs on only propane and relies upon good old thermocouple and a pilot light. I found those easier and more sane but then again I am 72 and worked with my father on gas controls when I was a teen. So I know propane and natural gas water heater safety controls and what they do well. This over complication instead of just using an old school pilot light thermocouple unit is beginning to a drain on the pocket book and it should not be that crazy to fix properly.
I don't have a gas ticket but I could easily pass the test if I was so inclined just a question of brushing up on the simple math of determining pipe sizes to gas volumes and the different gas densities a little. A little bit of simple math goes a long way. Unlike some young pups these days I read the books and do things right and do not think I know everything.

Here is a very good vid of how to check things electrical on a gas one mine is combo gas electric but the circuit is almost the same unit.

Thanks for any responses.
Eric

 

[Gkiesel]

If you go with the circuit board, look into Dinosaur electronics. They make better quality boards that is believe are less expensive.

 

[creativepart]

2016 was definitely in the years when the control board problems were going on. When I got my 2017 Adventurer I had some Atwood issues and my support rep at the factory (they used to have those) sent me a new board just in case. He said Atwood had 3+ years of bad control boards.

 

[reeman]

Thanks guys! I suspected that indeed that set of production years for the hot water tank had flakey issues, most likely quality control on early production line or production moved around too much keep up inspections. 2015-16 certainly did see a tonne of chaotic RV production and high demand.

Good part is we have trailer with plumbing that does not leak at all. Might change the external prv (pressure relief valve) on the unit though as it drips a little when the unit is on electric and up to temp. No signs of over heating because of lack of tank sensor contact. A really good tip for all rv owners of any description is to keep one of these in the utensil draw and regularly, at least two or three times per season check the actual hot water temp coming out of the kitchen sink. That is the place where most serious scalds can happen. If the temp is over 140f then chances are the tank eco sensor and second return control is not making adequate surface contact to the tank body. PRVs are designed to fail on the low pressure side so it is also a very good idea to exercise them. In other words test them by releasing cool water when the tank is not heated up but is under pump pressure. Exercising a PRV at least once a year keeps them from early failure. Ours is starting to fail so no big deal it will not cause the pex lines to pop by over pressurization of the hot side of the circuit. Good simple and regular maintenance practices can save big bucks, same as any complicated system with so many possible failure points to consider. Here is a link to the what to use it is a simple self explanatory device, it does require calibration but how to do that is obvious for anyone who has worked as a cook. Old school devices for some simple measurement procedures are still the very best and reliable IMHO. Here is the one that I like the best because I am bilingual in measurements, but there are some good analogue ones that speak only in Americanese degrees Fahrenheit

THE REAL BENEFIT of having a cheap and accurate commercial grade food thermometer in the trailer is that it is extremely useful at saving excess trips to the outhouse if the food is a little off and needs to be correctly cooked to food safe. There is absolutely nothing worse than having a nice trip to a beautiful campsite spoiled by having a case of having the trots after having the stomach reject the reheated chicken and gravy sandwich while camping!
Been there... got the soiled tee shirt.
Best wishes from Canada..
Eric

 

[l1v3fr33ord1]

reeman-

Over on the sister site, iRV2.com, there's a member named "Old-Biscuit" who has responded to thousands of water heater questions. Your winnieowners.com credentials (member name, password) will work over there, so if you haven't yet signed in to iRV2.com you should, and then look through "Old-Biscuit's" many posts there.