3-esy refrigerator does not cool on gas

[gsusan]

Looking for anyone to give me help or advice on my RV refrigerator not cooling on LP
Model: 3-way Dometic RM2193 1.9 cu ft. refrigerator without a freezer. Basic model without circuit boards or thermister. Four years old and just recently started not cooling on LP. Refrigerator is always level.
Facts: Works 100% on electric and 12 V
Orifice has been cleaned
Burner has been cleaned
Flue has been cleaned
Baffle has been clean and hangs correctly
Gas pressure checked and confirmed to be 11” water column
Gas filter is clean
Flame remains lit and has a tall, large and blue flame
The boiler sleeve (that holds the baffle) gets too hot to touch,
The bottom tube (perhaps called the liquid temperature exchanger) gets too hot to touch
The absorber vessel is just warm
The top absorber tube is hot but you can touch it and the other two tubes below are just warm
Dometic and their dealers in my area cannot offer me any additional suggestions or recommendations beyond what we have already done.
I would appreciate any ideas on what can be wrong. Thanks

[Chris_Bryant]

That orifice (and the flame) is so small, it doesn't take much to keep it from cooling properly. The other gas lines should be fine- they are sealed- though oil can clog lines as well- but the refrigerator flame is so small the other appliances would be impacted far worse.

[gsusan]

Thanks for the picture, we will look at this test port. Regarding the orifice, after we cleaned it what could go wrong with the orifice (we cleaned it with alcohol only, we did not poke anything in the orifice) We have a large blue flame. Can we have that good of a flame if the orifice is bad?
We will try and run the refrig. without the filter again. The gas line leading into the orifice, can that possibly be clogged with a spider web?

[Chris_Bryant]

The marked plug is what I was wondering about-


This will be a pressure test port after the valve, so you can check the valve by having the LP place measure the pressure at this point. If it is still 11" with it on high, the valve is fine and I would just replace the orifice. If it is lower, try without the filter, then replace the valve.

[gsusan]

Mr. Bryant, great to hear from you and I appreciate the help you gave me earlier.

The filter is the tiny one (approximately a ¼ inch) that sits just in front of the gas valve inlet. We did not clean it; however, it was very white with little dirt on it. In one of our testing procedures, we tried the refrigerator with the gas filter removed from the gas valve but it did not make any difference.

We went to an LP dealer (not an RV dealer) and he raised our pressure from 9” wc to 11” wc . He had an adapter that he inserted between the gas outlet and the refrigerator gas valve. He did the test while the refrigerator was on gas, on high. No other appliances in the camper were operating at that time. We only have a 3 burner stove and furnace in our truck camper pop up. After raising the water column, we did get 10 degrees cooler in the refrigerator. The refrigerator use to cool down to only 60 degrees and now it cools down to 50 degrees. The outside temperature is 80 degrees today. The LP dealer did not have any suggestions on what our problem could be.

I called Dometic and asked them if we had a gas bypass screw on our unit and they told me we did not.

We tried tapping on the gas valve and that did not help however, we do appreciate any ideas.

[Chris_Bryant]

Hey- small world 🙂 I really cannot see the valve being bad- its main function is as a safety device, and the flame regulation looks to be pretty basic.
When you say the filter was clean, are you talking about the filter on the valve inlet? How did you determine it is clean? Where did you measure the LP pressure?
There is a screw right above the gas valve outlet that interests me- from a picture, it looks like a bypass screw, but it could just be a pressure tap.

[gsusan]

Up date on our Refrigerator problem. Thanks for the suggestions. We have cleaned the flue and baffle earlier with no help to the cooling.

After 72 hrs of running the refrigerator on gas, the lowest temperature we can reach is 50 degrees. We did lower the gas valve to medium setting and that raised the temperature in the refrigerator to 60 degrees. If the gas value is our problem, is there a way the valve can be tested to confirm we have a problem with the value? The valve is a $135.00 non returnable part and would hate to buy a new valve it that was not the problem.

Thanks in advance for any ideas.

[enblethen]

Have you cleaned the stack? Use flexible wire to rattle the baffle!

[1492]

Moved from Forum Technical Support

[gsusan]

Thanks for the tip. We have checked and the ventilation is accurate.
We even took the unit out of the camper and into the garage and that did not seem to help.

[enblethen]

Ventilation problem!
Check distance from outer wall to cooling unit. Should be down to about 3/4 of an inch. Closing this gap will increase air movement through the cooling unit increasing efficiency.
Look at dimension M. Also look at top of refer to insure that the top is blocked off. Air should not be allowed to come over top of refer. A piece of thin flashing sheet metal bent into a curve will prevent this.
2193 manual