Problem with Dometic Refrigerator

[dphewitt]

The following happened over last 4 day trip.

Notice that the Dometic Refrigerator not cooling at all.

Using propane and the pilot light would light up. The flue baffle warm. However, not cooling regarding the refrigerator.

"Check light" does not go on indicating a problem. Both the "auto" and "gas" light goes on


Tried troubleshooting. The thermostat (in fridge)I raised as high as possible in fridge. Did not change temperature

At home I plugged in the electric cable but the fridge would not change to auto. Still would be on propane. No difference in the temperature.

I have started to look at fuse box in fridge compartment on the outside of trailer. Only problem right now I am having difficulty taking the cover off the fuse box!

Hopefully it might be simple solution of replacing a fuse. But where is the fuse located?

Any thoughts or suggestions greatly appreciated!

Dale

[SageRpod]

Hi Dale
Sorry to hear you are having an issue with the fridge. For starters make sure it is level. The higher the ambient temp is outside, the more important it is for the absorption fridges to be level. Second, I would check the thermal breaker on the back side of the fridge. Remove the outside panel, it will probably be behind heat shroud where the pilot light is. There is also a 5amp fuse on the "lower board"(the one located behind the outside panel). Check that fuse as well.

That should be a start. From my research when I had my Dometic issues, which turned out to be out of level, you will want to check those items first, but it could be the "top" board which is located in the brow panel where your buttons are for gas, auto, on/off, AC, etc...

[Chamberman]

If your propane burner is on then I doubt your problem is power related.
This says that the fridge is trying to cool.

If the propane burner is on and the evaporator is getting sufficiently hot then the fridge should work and begin cooling unless 1) the trailer is severely out of level, 2) the evaporator has plugged up due to the fridge being operated for too long out of level, or 3) the ammonia used as coolant has leaked out.

[dphewitt]

Originally Posted by Chamberman

If your propane burner is on then I doubt your problem is power related.
This says that the fridge is trying to cool.

If the propane burner is on and the evaporator is getting sufficiently hot then the fridge should work and begin cooling unless 1) the trailer is severely out of level, 2) the evaporator has plugged up due to the fridge being operated for too long out of level, or 3) the ammonia used as coolant has leaked out.

Thanks for the reply. Where the trailer is located it is on a slope (driveway). I realize that. But when we actually went camping previous week the trailer was indeed level. The refrigerator not once became cool. I am hoping that it might be a fuse, but the lid for the fuse box on back of fridge appears to be very difficult to remove. I don't want to snap or break the cover which maybe I will have to do

[Chamberman]

Originally Posted by dphewitt

Thanks for the reply. Where the trailer is located it is on a slope (driveway). I realize that. But when we actually went camping previous week the trailer was indeed level. The refrigerator not once became cool. I am hoping that it might be a fuse, but the lid for the fuse box on back of fridge appears to be very difficult to remove. I don't want to snap or break the cover which maybe I will have to do

If the fridge is commanding the propane to come on and heating the evaporator then it has power and its trying to cool. I do not see where any fuse is going to be the cause of your issue. The cooling system on these fridges is quite simple, if it got sufficient heating then it should be evaporating ammonia and it should be cooling.

I realize that you had the fridge level at your campsite and it didn't cool then, but if whatever was afflicting it then is now corrected but you have the fridge tilted too far in your driveway then you may have introduced another variable which is compounding the problem.

Whats the approximate slope in your driveway? My driveway is approx 4.5deg slope and I can tell you that our DM2663 fridge will not cool at this slope. I tried before I knew better.

[C&G in FL]

Just because you can get the refrigerator to light and you can see the flame, what you see is the pilot light. When the thermistor calls for “more cooling” (assuming the thermistor is not faulty), the burner should go to a higher flame. If it doesn’t go to higher flame, it will not cool down. Or, a partially blocked tube from the gas valve as well as a clogged orifice can prevent adequate flow to the burner.

[Chamberman]

Originally Posted by C&G in FL

Just because you can get the refrigerator to light and you can see the flame, what you see is the pilot light. When the thermistor calls for “more cooling” (assuming the thermistor is not faulty), the burner should go to a higher flame. If it doesn’t go to higher flame, it will not cool down. Or, a partially blocked tube from the gas valve as well as a clogged orifice can prevent adequate flow to the burner.

Our DM2663 has an electronic ignition, there is no idle standby flame when cooling is not being commanded. I agree there could be a blocked burner or something limiting the gas supply.

[SRS]

Originally Posted by C&G in FL

Just because you can get the refrigerator to light and you can see the flame, what you see is the pilot light. When the thermistor calls for “more cooling” (assuming the thermistor is not faulty), the burner should go to a higher flame. If it doesn’t go to higher flame, it will not cool down. Or, a partially blocked tube from the gas valve as well as a clogged orifice can prevent adequate flow to the burner.

My Dometic RM2454 has no pilot light. As Chamberman said, It has electronic ignition and either the burner grate is light and trying to cool (actually heat the ammonia) or it's not. the 3 cu.ft. Dometic I had in my 2011 Chalet worked the same way. If the burner lights that means you have 12 volt power to the frig so it's functioning or at least trying to.

[Rossue]

It could be a partially clogged orifice. I had that situation; there was a flame, yet it was wimpy. Soaking the orifice in alcohol for 20 minutes fixed the cooling problem.

[escape artist]

Originally Posted by dphewitt

The following happened over last 4 day trip.

Notice that the Dometic Refrigerator not cooling at all.

Using propane and the pilot light would light up. The flue baffle warm. However, not cooling regarding the refrigerator.

"Check light" does not go on indicating a problem. Both the "auto" and "gas" light goes on


Tried troubleshooting. The thermostat (in fridge)I raised as high as possible in fridge. Did not change temperature

At home I plugged in the electric cable but the fridge would not change to auto. Still would be on propane. No difference in the temperature.

I have started to look at fuse box in fridge compartment on the outside of trailer. Only problem right now I am having difficulty taking the cover off the fuse box!

Hopefully it might be simple solution of replacing a fuse. But where is the fuse located?

Any thoughts or suggestions greatly appreciated!

Dale

Hi: dphewitt... Our original Dometic 7 cu ft. doesn't auto any more. We have to manually change over the cooling source. IMHO it's a bum mother board. Only trouble is the airfare for parts from Sweden is atrocious!!! Alf
escape artist N.S. of Lake Erie

[sameo416]

Dinosaur makes high quality replacement control boards for most Dometic fridges.

https://www.dinosaurelectronics.com/Dom_boards.htm

Not all models. Our 2683 Dometic (2021 5.0) presently has no Dinosaur board available.

[C&G in FL]

Originally Posted by SRS

My Dometic RM2454 has no pilot light. As Chamberman said, It has electronic ignition and either the burner grate is light and trying to cool (actually heat the ammonia) or it's not. the 3 cu.ft. Dometic I had in my 2011 Chalet worked the same way. If the burner lights that means you have 12 volt power to the frig so it's functioning or at least trying to.

“Pilot light” was a poor choice of words on my part. When the electronic ignition lights, close examination will reveal a small circular blue flame. When the thermistor “calls for more cooling” the flame should increase, accompanied by what could be described as a “whooshing” sound. If the small circular flame is all you see it is not functioning properly and it is not going to get cold. It may be trying to function as stated, but it is not functioning properly. My point was that it could ignite, flame may be present, but that does not signify proper operation.

[SRS]

Originally Posted by C&G in FL

“Pilot light” was a poor choice of words on my part. When the electronic ignition lights, close examination will reveal a small circular blue flame. When the thermistor “calls for more cooling” the flame should increase, accompanied by what could be described as a “whooshing” sound. If the small circular flame is all you see it is not functioning properly and it is not going to get cold. It may be trying to function as stated, but it is not functioning properly. My point was that it could ignite, flame may be present, but that does not signify proper operation.

Thanks for the clarification. I haven't spent long periods of time observing the actual flame so I can't speak with certainty if the flame increases for cooling. What I have observed is that the sound the flame makes and it's size doesn't seem to change. It is either on or off.

When I first got my trailer, the Dometic RM2454 would stop working on propane and the check light would come on. It was very sporadic in that it might run for only a couple of hours or sometimes 5 days. Turning the frig of and on again would reset it and the gas would light. I often had the lower exterior panel off while I was troubleshooting the issue so I could observe the flame. I decided the problem could be the gas regulator at the propane tanks might be set incorrectly. All the appliances in my trailer require 11 inches of Water Column (WC). So, I got the tools and tested the gas supply at the frig and the pressure was 14 inches WC, or too rich. I adjusted the pressure down to 12 inches WC and since then the frig has run flawlessly on propane. This is a long winded way of saying that during all this troubleshooting, the flame appears to have the same output and sound whether it's just been started and the frig is warm inside or running for a week and full of food.
Different models may do different things so, as you have said, maybe all these frigs have a low flame mode and a higher flame mode for better cooling. Frig problems are frustrating and for me it's one of the most important appliances in my trailer since we like to boondock. I hope you solve your issue soon. By the way, have you looked at the many video's on MyRVWors.com? I found them very helpfull.

https://myrvworks.com/

[rubicon327]

Originally Posted by Rossue

It could be a partially clogged orifice. I had that situation; there was a flame, yet it was wimpy. Soaking the orifice in alcohol for 20 minutes fixed the cooling problem.

Yes. Several times I have detected poor performance and cleaned the burner and orifice which corrected the problem. It is very hard to tell by eye if the flame is weak or not. Another very important item is checking proper propane pressure. Regulators go bad or sometimes just need adjustment. I have found that measuring 12" w.c. with no other loads at the fridge test port is just right and keeps it from dropping below 11" w.c. with load. Tutorial here in an old post: https://www.escapeforum.org/forums/f...tml#post260752

[C&G in FL]

As Rubicon (Dave) stated, clogging can be a problem. Propane can have “impurities” in it. There is a thin tube that goes from the gas valve to the burner assembly. It, too, could be somewhat clogged restricting the flow of propane. Remove it and blow it out with a compressor. If it is blocked, the high pressure air will blow out the crud and it will be visually evident. And also as Dave mentioned, looking at the flame it may be difficult to tell what is going on, but in my experience with Dometic fridges, sound is the key. If you cannot hear the “whoosh” (similar to the sound you hear when you light a Bernzomatic torch), the flame hasn’t kicked up to high and it is not going to cool. Of course, age sometimes results in reduced ability to hear in some folks. I am in my 70s and am fortunate in that my hearing is still relatively good, and can hear the difference without having to remove the outer hatch. However, I would suspect that a person who relies on a hearing aid would be able to hear the difference.