Dometic RM2852 stopped working

[carlgren]

For a day or so the lower vent on my fridge was being intermittently blocked by a piece of plastic flapping in the wind. We noticed a day or two later that our fridge had stopped cooling.
While troubleshooting it I found the reset on the boiler had tripped so I pushed it back in. All the electronics and voltages check out and the boiler is getting hot on electric or propane but I am not getting any cooling. The lower coils are not warm to the touch.
I have run the fridge on both electric and gas for 24 hours and other than the boiler being almost too hot to touch nothing else seems to be happening.

I read somewhere that flipping the fridge over for a couple hours and then back upright and letting it sit for 24 hours before turning on can fix them if the coolant isn't moving.

I have no way of moving the trailer and there are no RV places anywhere near me. A new cooling unit is over 3500 in Canada so that's not much of an option either.

Has anyone ran into this before and found a fix?

Thanks
Don

[trailrydr]

Ive read that you can also tap on the coils to breakup any buildup.

[carlgren]

Thanks Jim,

I'll be giving that a try tomorrow. I think they left me enough propane line that I can pull it out 4" or more without having to disconnect anything to give me access to tap on the coils for the day.

I'll post any success I have.

Don

[stroguy]

I would do a complete power down, 120 and 12. Let it sit for 10-15 minutes with our power. Have you looked up the duct to make sure there is no blockage there as well? The control board possibly is locked up. Or the control board is bad due to the blockage of the vent and it overheated or over worked.

[carlgren]

Hi Randy,

I checked the fuses and the thermostat in the fridge and did every other test I could find and all the electronics tested out OK. I've also left it off and unplugged (12 and 120V) for a day to see if that helped. It passed every test and seems to work fine otherwise. It also switches to propane if I unplug it from 110 and switches back when I plug it back in. Just no fluid movement seems to be happening. Also no odor of ammonia and no yellow residue anywhere.

Don

[huntr70]

Shut it down completely, unhook the lp line, and pull it out and "burp" it.

Google search for "burping an rv refrigerator". It works....

[Second Chance]

Shut it down completely, unhook the lp line, and pull it out and "burp" it.

Google search for "burping an rv refrigerator". It works....

Here's one process I posted some years back (it shows up on the forum in several threads):

I originally posted this a couple of years back after problems with our Norcold 1210. A very good tech taught be about the absorption refrigerator "reboot." Perhaps there's something in here of use:

Our absorption fridge quit cooling last winter (had been in one site without moving for a couple of months). I called our trusted RV tech for advice... I posted the following after that experience:

RV techs call it a "refrigerator reboot."

When your absorption fridge quits cooling (cooling unit less than two years old) and an experienced RV technician tells you to do a "fridge reboot," listen to him/her. Late last week and over the weekend our Norcold 1210 fridge started not maintaining proper temperatures. I tracked it with a fridge/freezer thermometer and my infrared thermometer and got an ever-tightening knot in my gut. First thing Monday morning I contacted our favorite technician here in Las Cruces, NM, Richard's RV Service, fearing the worst. He asked the following questions:
Is it the same on AC and propane? Answer: Yes.
Did the problem come on suddenly - like flipping a switch? Answer: No.
Did you smell ammonia? Answer: No.
Do you see any yellow residue around the boiler, coils, or any of the other tubing on the cooling unit? Answer: No.
Do you hear the cooling fans in the back cycling on and off? Answer: I haven't noticed them like I usually do - but the weather has been cooler.

Richard's instructions: Turn the fridge off for at least five hours and let everything get down to ambient temperature in the back. Using a rubber mallet, periodically tap on all the pipes, tubes, and other refrigerant conduits I can reach, both while it's cooling down and after it's completely cooled. This process took until about 2:00 Monday afternoon. I then turned the fridge back on and continued to do the "rubber mallet frappage" periodically while the fridge was warming up/cooling down. I turned the fridge back on mid-afternoon and by the time we went to bed Monday evening, both the fridge and the freezer were getting back down in normal ranges and the infrared readings on the fridge fins and the back walls of the freezer compartments were very good.

I kept a log and updated Richard a couple of times on Tuesday and he dropped by yesterday (Wednesday) to check. His diagnosis... an air bubble or chemical membrane in the refrigerant system. He said, "Congratulations!" and pronounced the fridge healthy. We both think the issue occurred because our RV hasn't been moved since we pulled onto this site on 10 November and the jostling an absorption refrigerator gets bouncing down the road helps keep the refrigerant stirred up and moving.

Rob

[carlgren]

Hi All,

Thanks so much for all the advice! We pulled it out, rolled it around inside the trailer, beat on the coils gently with a mallet for an hour or so and put it back in. Working like a charm now. Freezer is down to -18C and the fridge is down to 4C after about 5 hours. I figured we were OK when every time we rolled it we heard more gurgling. Getting it out was a challenge and we were beginning to wonder if we were going to be able to but with enough persuasion it finally came out. Putting it back in was a piece of cake.

What a relief!! We only need this trailer to last until we build our new house so we really didn't want to be replacing things like a fridge.

Don