Help troubleshooting Dometic refrig.

[German Shepherd Guy]

Hello guys. I need help please.
Dometic Refrigerator. Made 2017. Model DM2852RBFX. Lights just fine on propane. Runs for anywhere from 5 minutes to several hours but then just stops. Re-lights easily and repeats above symptoms. Plenty of propane in tanks, all other propane systems working as normal. I blew out the pilot and the burner with forced air to see if maybe something was restricting the gas flow. Made no difference.
Not sure what to look for next.

When it is running gets plenty cold and in all other respects acts normal. The baffling thing to me is how easily it re-lights, and then works for a time.
Any ideas?
Thanks
Oak
The not so many German Shepherds as we used to have guy.

[JRTJH]

What's your elevation ???? Both Norcold and Dometic recommend operating their gas/electric refrigerators on electric above about 8000'. There's not enough oxygen in the air "up there" to reliably reignite the flame once it shuts down after the thermistor calls for shutdown when interior temperature meets the set point.

This may not be your problem, but if you're above 8000', I wouldn't spend a lot of time "tearing things apart" until you get to lower elevations and verify that the problem still exists.

Just run it on electric until you get lower. I know that's not an "ideal solution if you're dry camping" ..... but......

[German Shepherd Guy]

That's an idea I had not thought of. Kicker is it has worked just fine in the past here. For many days on end. We are right at 8,000. But that would explain why it always re-lights I suppose. As I am forcing the re-light by turning it off and then back on? Do you think that the internal temp setting would have anything to do with this? I currently have it set for as cold as it can get. Today I will set it a bit lower and see if that has any result. I did notice there is a small black box shaped control of some sort located right on the gas jet. It is a 12v item with a wire in and out that I am assuming controls the spark in the igniter. I noticed it was extremely hot yesterday, but then it is located not far from the pilot light and the burner. ???

[Lee]

Hum, Over Temp sensor failing?

[JRTJH]

I can't explain the "WHY" or the "WHEN" concerning high altitude gas failures in absorption refrigerators, but Norcold and Dometic both have the "disclaimers" about operating above 5500' altitude "MAY" cause problems and operating above 8000', both recommend operating on electric setting only.

There are well documented discussions about this issue on all the RV forums and it's a "fairly well recognized problem", but it's also an "inconsistent problem" in that some people never have an issue while other people say their refer works well at 6000' but fails at 7000' while others will say their refer works at 10,000' and they've never had any problem....

I don't know why there is such a wide difference in the operation and some work, others don't work....

My point was to just say that "tearing it all apart to find a problem" may not give you any fix and it may all be "wasted effort" since nearly everyone with an absorption refrigerator will have issues as they go up in elevation. Some fail significantly lower than others and there's no "rhyme nor reason" to why or when.

I'd hold off on spending lots of time on it and possibly breaking a part or making matters worse, when there's nothing "wrong" or "that needs fixing", as it's a known issue with nearly all Norcold and Dometic refrigerators.

Frustrating? Hell yes. But it's not a "broken part" kind of failure, but rather a "happens to most of us at one time or another" kind of thing.....

[RV Vacation]

Originally Posted by German Shepherd Guy

Hello guys. I need help please.
Dometic Refrigerator. Made 2017. Model DM2852RBFX. Lights just fine on propane. Runs for anywhere from 5 minutes to several hours but then just stops. Re-lights easily and repeats above symptoms. Plenty of propane in tanks, all other propane systems working as normal. I blew out the pilot and the burner with forced air to see if maybe something was restricting the gas flow. Made no difference.
Not sure what to look for next.

When it is running gets plenty cold and in all other respects acts normal. The baffling thing to me is how easily it re-lights, and then works for a time.
Any ideas?
Thanks

The not so many German Shepherds as we used to have guy.

Possibly carbon build up??? Just throwing out some food-for-thought. I am thinking your fridge is "locking-out" the pilot light because it is taking to long to relight and possibly not getting the signal back to the controller in time to maintain a flame.

Plenty of internet "how-to's" regarding the cleaning of "pilot lights".

[German Shepherd Guy]

So went out today and hooked it into AC power and the same scenario played out under electric power. Works fine for 10 minutes to 60 minutes and then stops. Re-starts as soon as I push the buttons and then the same thing, just as it did with propane. Anyone have some thoughts? There are two control panels. One in the back and one in the front. Frankly I am stumped.

[JRTJH]

Oak,

Does it run properly on electricity? If it does, and if you're at 8000' elevation, I would recommend not "digging into things"... The propane burner jet is a "laser drilled spiral hole in a man made ruby". It's set in the brass body and is very fragile. Sometimes you can use a nylon bristle toothbrush to clean the carbon deposits from the orifice and it will work OK. On the other hand, sometimes you can just blow a little air over the orifice and it will dislodge the ruby insert and you destroy the burner. In other words, it's fragile and easy to damage.

Dometic recommends to clean the jet, soak it in alcohol for about an hour then gently dry it and use LOW PRESSURE AIR to blow the jet clear of alcohol. The problem with that is that sometimes the compressor air is "dirtier than the carbon".... So.....

If it runs on electricity, I'd leave it alone and next time you plan a trip with shore power (so you have a backup if the propane burner fails) then tow the trailer and try the propane system at lower altitudes to see if it works properly. If it does, your problem is not the refer, but the altitude. If it doesn't work at lower altitude, then start your troubleshooting...

At this point in time, any troubleshooting you do may do more damage than good.

[German Shepherd Guy]

Howdy John. Well I went out and tried it on AC and the same thing happened. 10 to 20 minutes and then shut down. Re-starts easily. I have a call in to Dometic (they were closed by the time I had tried the AC power) and I talked to a friend who is in H & AC stuff. He told me that the components of an RV fridge can (the stuff that cools the fridge) separate if it sits too long. Well as we have retired and haven't been to any dog shows in over a year this thing has sat a lot. So, this week I am going to hook it up and drive it up to the lake and back and see if I can shake it up. That MIGHT help. Might not but it is a cheap try. I will let you all know what Dometic has to say after I talk to them tomorrow. Any other thoughts will be appreciated.
Oak the frustrated.

[German Shepherd Guy]

Well it is fixed. And an interesting solution. called Dometic and was able to get a tech after several tries of only getting a computer. Symptoms. Both on LP and electric would start and run fine for 10 minutes to an hour. and then would shut down. Could be easily restarted but would repeat the above scenario. I was stumped after trying a bunch of things. Tech said to her it sounded like a 12v supply problem. ???? Really? All other 12v systems were working, but she insisted I try to locate a faulty ground. Was not a faulty ground but IT WAS a 12v supply problem. This summer i tied 2 solar panels into the system as my 2019 had a direct input for them. What I failed to do was put a charge controller into the line. What I was getting was a HIGH voltage on my 12v line. The refrigerator depends upon a 12v supply and it must be even and consistent. During the day when the sun was directly on my panels i was getting way more than 12v and the refrigerator would shut down. At night I was not and was why I would operate for 8 plus hours without the fridge shutting down. It was that way with either the shore power or the LP power. I will be adding a charge controller and thid is a cautionary tale for all those adding solar to your power supply.
Thanks for the troubleshooting help.
Oak
The relieved it was a simple fix.

[ObiRich]

Originally Posted by German Shepherd Guy

Well it is fixed. And an interesting solution. called Dometic and was able to get a tech after several tries of only getting a computer. Symptoms. Both on LP and electric would start and run fine for 10 minutes to an hour. and then would shut down. Could be easily restarted but would repeat the above scenario. I was stumped after trying a bunch of things. Tech said to her it sounded like a 12v supply problem. ???? Really? All other 12v systems were working, but she insisted I try to locate a faulty ground. Was not a faulty ground but IT WAS a 12v supply problem. This summer i tied 2 solar panels into the system as my 2019 had a direct input for them. What I failed to do was put a charge controller into the line. What I was getting was a HIGH voltage on my 12v line. The refrigerator depends upon a 12v supply and it must be even and consistent. During the day when the sun was directly on my panels i was getting way more than 12v and the refrigerator would shut down. At night I was not and was why I would operate for 8 plus hours without the fridge shutting down. It was that way with either the shore power or the LP power. I will be adding a charge controller and thid is a cautionary tale for all those adding solar to your power supply.
Thanks for the troubleshooting help.
Oak
The relieved it was a simple fix.

Now you should do one more thing...If your voltage was that high, you may have damaged your batteries. Check for water level, and you may want to test them to make sure they're both still good.