Somewhere along this trip the gas side of our water heater stopped working. Electric works fine. Ideas?
Flame sensor (Thermal Link)?
How far into the "working on gas" does it get?
Ignitor clicks
Gas valve opens
Flame, but goes out
Responding to this type question, I used to always say "Read the trouble shooting steps in the manual". I still think this is good advice. If you don't have the manual in your coach owner books, you can find them online. In the one linked below, scroll down to page 15 to find the section on the DSI models.
https://myrvworks.com/wp-content/uploads/2019/04/Atwood-Water-Heater-Service-Manual.pdf
But these days, when I have a problem with practically anything, first thing I do is go to YouTube and look for a video. Almost always find something helpful. The one linked below gives a pretty good sequence of steps to check the 12V power flow. It mentions the thermal cutoff fuse. That thing went bad on our heater one time. Replaced it and we were back in business. Photo below shows the location on our water heater.
Amazon.com: RV Water Heater Thermal Cut Off Kit Replacement for Atwood... (https://www.amazon.com/Thermal-Electronic-GC6AA-9E-GCH10A-2E-GH610-3E/dp/B07K9KNRB5/ref=pd_lpo_3?ie=UTF8&tag=foreforums-20)
One other thing - if you decide you need a new circuit board, I recommend you get the one from Dinosaur. Excellent quality! Call them and ask if unsure which one you need.
Ignitor Board Index page (https://www.dinosaurelectronics.com/Ignitor_boards.htm)
https://www.youtube.com/watch?v=IyJWLmlnQ4I
To close out the thread, when I finally got somewhere to trouble shoot I found no spark and good gas. Using the multimeter I confirmed bad board. Unfortunately we weren't somewhere long enough to order the board and have it delivered so I simply wrote the check to an RV repair facility and that solved the problem. I do plan to order a spare board to have as this is the second board in the five years we've owned the coach that I've had to replace. Thanks to all who responded. Perfect advice.
Now, IIRC if you don't need your propane heater, you can use the control board in the Hot Water heater, it will just have a time delay before it starts.
Propane water heater: In an emergency on some models, 12 volts through temp sensors to gas valve will start gas flow, which can be lit with lighter.
If gas flame blows out, gas will not shut off.
When tank temp reaches set point, flame will go out, but a later auto restart when temp reduces below set point gas will flow without flame.
It works, just monitor it, then shut if off. You have a hot tank for showers. No reason for cold showers out at a campsite. Fix it when you get home. . .