Atwood (Dometic) furnace

[tkemnitzer]

We have a 2017 travel trailer. When we fire up the Atwood furnace, it will ignite and run for maybe 3 to 5 seconds and then it stops heating and fan only. After the 3 times it will not ignite again, fan only. Any thoughts? Thanks!

[Gotitmade]

Go to UTube. Look for RV Furnace working intermittently. Look for videos by a person using the name "MY RV WORKS". He does have several videos about Atwood Furnaces and water heaters. He posted one titled "Atwood 8531-IV RV Furnace With Intermittent Heat" which I followed and it was exactly what my problem was. Good Luck.
Ed

[ebrabaek]

This is what was wrong with mine. Next video was how to fix it. Yours could be different.

https://youtu.be/QEVDrKCGLg0?si=P3Z9IGhIVce28gyF

[5picker]

Well, you didn't tell us whether other LP systems work correctly so shall we assume your LP supply is OK?

Are you on shore power or running off battery?
Has your furnace worked correctly in the past?

From the little information you gave us it "sounds" like it could be a flame detection issue. That could be caused by several things.

Have you downloaded the manual for your model furnace and went through the troubleshooting procedures?

[njfishing]

First thing I would do is bleed your propane lines by lighting the stove. If it takes the stove a long time to light this is likely your issue.

It would also help to let us know if you are plugged into power and if all your other propane things are working like the stove and hot water heater.

[Flybob]

May or may not be your problem, but good info to know.

If an RV sits for a while ( month or so the pressure in the propane system can drop if the tanks are turned off. If you open the tank valves too rapidly and the pressure is low, there is a good chance that you could trip the free flow protection in the tank. This will shut off the propane flow. To correct this, turn valve off, wait 10 mins or so then turn the valve on very slowly until you hear the slightest amount of flow. Stop and wait a minute or so to pressurize the lines, then open the valve the remainder of the way. If you hear a click in the tank, you tripped the free flow protection and need to try again.

[tkemnitzer]

Originally Posted by Flybob

May or may not be your problem, but good info to know.

If an RV sits for a while ( month or so the pressure in the propane system can drop if the tanks are turned off. If you open the tank valves too rapidly and the pressure is low, there is a good chance that you could trip the free flow protection in the tank. This will shut off the propane flow. To correct this, turn valve off, wait 10 mins or so then turn the valve on very slowly until you hear the slightest amount of flow. Stop and wait a minute or so to pressurize the lines, then open the valve the remainder of the way. If you hear a click in the tank, you tripped the free flow protection and need to try again.

Lines have full propane and I am plugged into shore power.
I always light stove before I start furnace and/or frig to make sure I have a good propane flow.
Thank you.

[wheelin14]

Back around 2019 Dometic Atwood had a run of faulty sail switches that would not swing far enough to make contact indicating full air flow. I’m not sure if it extended back to 2017. I would contact Dometic with model and serial number to see if there are any service bulletins. Sail switch, over temperature switch , and the circuit board are all likely culprits.

[tkemnitzer]

Thank you.