2009 3600RE w/Dometic RM3962 strange cooling issue

[jingle]

We keep our RV set up and operating on our acreage in the Texas Hill Country. The frig has been working without fault for 4 years. Several weeks ago my wife told me the frig was making a making a low, rumbly sort of moaning sound. My hearing is not all that great and I didn't really notice it. A few weeks later we came out for the weekend and found the frig on 60 degrees. I put bags of ice in the frig, and freezer, hoping it would help the unit get over the hump. It did come down to about 45 degrees for the remainder of the day, and the freezer would keep ice. The next trip, the freezer seemed to be operating fine - not sure of the temp - but the frig was 60 degrees again and stayed that way for three days while we ate out of ice chests. We left it running and tried contacting a service company (under extended warranty) to come out and fix it. We came back two weeks later to find that the temperature had come back down to 42 degrees (all the time kept on 5 - coldest). We had scheduled to meet a repairman, who was half a day late, making us have to step out briefly to take care of business responsibilities, and he arrived while we were gone (after being told that he would not be arriving during our brief absence. He let himself in without our permission with some sort of master key (how does THAT work?). We had described the behavior to him, but he called us after he had already left and said the unit was at 46 and appeared to operating just fine. I repeated the symptoms to him so that he would understand the issue and he asked me if I know how these things work. I said, "Yes, I do." He condescendingly said, "Let me tell you how these things work." I told him that I know how they work, I'm an engineer. In his best hillbilly voice, he said, "I don't believe I'm gonna be able to hep yew," and hung up on me. I think he was the only guy in the area who works on RVs. I really don't want to hire a driver to take my RV 75 miles each way to get the frig fixed, but may have to. Very odd behavior - I don't know if it' a cooling issue or a control issue. The fact that the freezer will keep ice doesn't sound so much like a cooling issue, but I don't know how this unit is plumbed. Any advice is appreciated. I understand how they work but it's been decades since I kept boxes of refrigeration tools and equipment.

 

[jimtoo]

Hi jingle,

Welcome to the Heartland Owners Forum and to the family. We have a great bunch of folks here with lots of information and all willing to share their knowledge when needed.

You might pull the lower outside cover off and take a look under and at the piping for the fridge. If it is rusty and/or you see a yellowish stain or oil you will probably need a new or rebuilt cooling unit.

You said it's 75 miles,,, to nearest dealer or your house? Where is your unit parked? We may be able to give you a better repair service. location.

Jim M

 

[danemayer]

The fact that the freezer will keep ice doesn't sound so much like a cooling issue,

Hi jingle,

If the freezer is cooling down close to zero F, then your cooling unit is probably ok. You may have an air leak. If one door has a flap, make sure it's closing properly. If it binds, all your cold air will leak out. Also check the cooling fan(s) on the backside of the frig. The rumbling sound might be a problem with the fan. If the fan fell down or has failed, the hot air on the back side won't be moved properly and cooling will be poor.