Dometic RM2652 not cooling

My opinion is you don’t have enough flame. A very slight pressure loss can cause a significant loss of cooling. Regulator failure is very common.

jkwilson wrote:
My opinion is you don’t have enough flame. A very slight pressure loss can cause a significant loss of cooling. Regulator failure is very common.

An earlier poster also mentioned he thought the flame was inadequate.

I will rig up a manometer tomorrow and check it. The diaphragm and spring in the regulator is 17 years old also, so it's not hard to imagine that they have changed in some regard. Thanks John

Main REG ---17 yrs old......you got your monies worth
REPLACE the Main LP REG

Pull the flue baffle and clean it
Swab the inside of flue just to clean it up
(Cover burner or you will need to remove and clean it due to rust falling down when swabbing the flue)

Your flame is 'small' therefore COLD
Your flue baffle is rusted up...inhibits heat transfer

Afterwards ...propane should cool as well as the element did.

I have a Marshall regulator on order and tomorrow I will slide the fridge out so I can access the flue for cleaning. I'll get back and let you know if this solved the problem. Thanks to all who helped, especially Old Biscuit.

Travelin2 wrote:
I have a Marshall regulator on order and tomorrow I will slide the fridge out so I can access the flue for cleaning. I'll get back and let you know if this solved the problem. Thanks to all who helped, especially Old Biscuit.

Shouldn’t have to move the fridge to clean the flue. Check out this video to clean the burner and flue. https://m.youtube.com/watch?feature=youtu.be&v=_cmE7iN3D9I

The only other thing I would add to this thread is the small flame could be caused by rust partials falling down inside the burner tube blocking the propane flow. I used to get rust flakes that would fall down from the flue that would block the slots on the burner tube that I would have to vacuum off or blow off with a straw. After a while this would no longer work I removed the tube itself to clean it and the orifice and noticed the tube was filled with very fine rust like a power. I cleaned that out and all was well again. The slots in your burner tube look good after 17 years so your air mixture is probably alright. If you haven't cleaned the tube out recently try that first and see if that helps.

Gjac wrote:
The only other thing I would add to this thread is the small flame could be caused by rust partials falling down inside the burner tube blocking the propane flow. I used to get rust flakes that would fall down from the flue that would block the slots on the burner tube that I would have to vacuum off or blow off with a straw. After a while this would no longer work I removed the tube itself to clean it and the orifice and noticed the tube was filled with very fine rust like a power. I cleaned that out and all was well again. The slots in your burner tube look good after 17 years so your air mixture is probably alright. If you haven't cleaned the tube out recently try that first and see if that helps.

Thanks for those tips. I am just headed out back to start in on that very project. It is finally up to 57 degrees outside so I guess it's safe get out there.:)I intend to clean it all up from the gas orifice to the top of the flue, looking for any possible problems. Thanks for pinpointing some areas to examine.

Several guys have mentioned that they thought my pressure was low so I figured I would test that before I got too carried away with replacing things that very well may be OK. I spent about a half an hour looking for the manometer I made years ago and finally figured it got tired of waiting and left for more excitement. I spent $7 at Lowes for stuff to make another one. Turns out you characters were right. This is a picture of the gauge as it has been running. I would call it 4.8 on the plus and minus side so it was operating on 9.6 inches of water column pressure.



I adjusted the diaphragm and now it is at 11 in/H2O


The flame does look a little different. The first picture is 9.6 IN/H2O. The second is at 11 inches H2O






Before I tested the pressure, I slid the fridge into the RV and set it on a throw rug so I could work the flue over. I ran a shotgun brush through it many times back and forth and spinning it. Then I shoved a wad of aluminum foil through it a few times to get the dust wiped out. The baffle was real rusty so I put a coarse barrel sander on my dremel and got that all shiny metal again. I reinstalled it and hooked everything back up. It's running through the night and I will check the temp in the morning. The electronic sensors said it wass 60 degrees at 2:30 this afternoon when I closed the doors.

Well, after all this messing around, I know I have the flue and baffle clean. The orifice is clear. The burner tube is clean. The lighting mechanism works fine. The propane pressure is correct.The vents in the RV body are good and still, after running it for 48 hrs with the thermistor wire unplugged, the fridge is only down to 40F. The ambient air temp. has been in the 60s, so if it got up in the 90s, it wouldn't keep up at all. Only thing I can think is that somehow the refrigerant isn't circulating properly since the coils in the back get barely warm to the touch. Much cooler than others I have been around. Is it time to bite the bullet and junk this thing? What else might I try?

So what temperature readings do you get if you switch to electric?

What kind of shape is the refrigerator door seal in?

Does the condensate drain tube have a restrictor or S-bend in it to reduce air infiltration?