Dometic Refrigerator Problem

[cbr46]

We have a Dometic DM2852 fridge that gets up to almost 50F on warm days (above 80-85F). On cool days (below 75F) the fridge maintains a nice 38-40F. The freezer never gets above 0F.

It seems the last year or two the problem has been getting worse . . . . or I just never noticed before.

There's surface rust around the burner but the burner tube itself is clean inside and out. There's considerable rust dust / flakes at the bottom in front of the burner. I can put my finger up inside the flue and it's relatively smooth (no rust flaking off). However, the spiral baffle is ~2" from the bottom of the flue and concave _^_ in shape. It's jagged from being rusted away by the flame. I tried taking a photo of the inside of the flue but no dice. The baffle moves freely up & down.



The fridge door seals are good. The frame where the seals seat is relatively good. Some corrosion at the bottom has started but not enough IMO to cause the fridge to "leak" air.

There's no ammonia smells, yellow, white deposits, etc.

I don't have enough data to compare to 120V. Almost 100% of my camping is without services (dry camping, boondocking, whatever).

How critical is the spiral flue baffle in maintaining good efficiency?

Other places to look?

Thanks,
- bob

[cbr46]

dougrainer wrote:
The baffle IS critical. BUT, it would be best to run the refer hot wired to 120 bypassing the controls for a few days in the temps you have the trouble in.

Yeah, that's the problem - finding temps >85F before next summer. I can get the fridge to freeze with the Dinosaur board.

BTW, the exchanger at the top looks clean, but I'm looking at it through the exhaust screen on the roof (vent cap removed). It's hard to tell if there was a deflector forcing all the air through the exchanger. Plus it's been over a month since I looked. I don't remember the gap size (1"? 2"? 1/2"?), but I pull the fridge out I'll reduce that gap to almost nothing.

Installing a bank of exhaust fans . . . . I'm running on 12V most of the time. OK, I run a generator so I can watch satellite tv at night. Still, I'm not fond of a constant drain on the batteries. Solar solution? Or just fix what needs fixin.

Best,
- bob

[drsteve]

Have you checked for blockage in the roof vent?

[wa8yxm]

Something I did on my Original was install exterior fans..

Well when it finally failed (Died of old age) my Service technician pointed to the "Crud" that had collected on the bottom of the outside heat exchanger.. It was not (yet) serious but it was perhaps 10-20 percent blocked.

NOTE: In 14 years I never did any work on it save defrost. It worked for the most part flawlessley (Oh one time it failed but it was a dirty connection. Unplugged and replugged the comm wire between the control box and the eyebrow a few times and all was good again.

Very happy with it... But as I said constant operation for at least 11 of thosew 14 years.

Alas it's now out of service for reasons that have NOTHING to do with it. (Entire RV is out of service)

[dougrainer]

The baffle IS critical. BUT, it would be best to run the refer hot wired to 120 bypassing the controls for a few days in the temps you have the trouble in. A partially blocked CU will operate just as you described. That is why it is critical to do the 120 volt test. Partially blocked CU's will still operate the freezer temps correctly. Doug