Another Dometic freezer working, fridge not...

[erkme73]

I was going to post this issue in one of the multiple threads with the same issue, but seeing as none of them were recent, I figured most subscriptions were either being ignored or they're outdated.

I have a 2002 NDR1292 side-by-side w/ice maker that was working well on the last 3 trips. This time the fridge didn't cool down, but the freezer was icing up (and making ice) just fine.

The initial cool down for this trip was on propane, but I switched to AC last night when I arrived at the campsite. I have 5 cold settings. I tried 3-5 but all kept the fridge just slightly colder than ambient cabin temp.

The thermistor clip is on the right-most fin, and I moved it all the way to the top based on other posts here. No difference.

This morning I found just a little condensation on the reefer fins (about 1/4 way up from the bottom).

I tried checking the flu but don't have the right tools to get the cover plate off. Does the flu matter for AC or only gas?

Both electric heating element leads are very hot. All the gray tubing is either very warm or hot. I looked up both coils with mirror, and all seemed clear - no insulation or bird's nests.

When I stick my head in the freezer, I can hear a bubbling sound.


There is about a 4" gap between the cooling fins and the food in the fridge.

I do not have a thermometer, so I can't gauge the temps accurately.

Lazy Day's RV is about 30 miles from here, and I intend on visiting them out of shear desperation. I just don't want to miss something obvious...

[RV Wizard]

That unit should have a couple of fans on the back side of the cooling unit and should run in hot weather. They could be the source of the unit not cooling the fresh food section. You can put in a temporary fan at the bottom of the unit blowing up and see if the temperature in the fresh food section will come down in a few hours. If it pulls down, then pull the refrigerator out to diagnose the reason the fans don't come on.
Otherwise the problem can either be a cooling unit low on refrigerant or the cooling unit has a restriction into the second stage evaporator. A new or rebuilt cooling unit will be needed.

[erkme73]

Thanks RVW...

I did not fan any fans anywhere under the outside panel... Were the fans possibly an option?

FWIW, by the time we made it to Lazy Days, the fins in the reefer were showing pretty significant condensation, and by the end of the four hour wait at their facility, there was ice at the bottom of the fins.

They told me there was no way to check pressures, no way to know if the unit was failing internally since they are a sealed unit, and suggested that I buy a new cooling unit for approx $2k. I told him since this was the first time I've experienced any trouble, and it seemed to have cooled by the time we got there, I'd rather wait.

Total bill $155 for 1 hr diagnostics (included .5hr for trouble shooting hard starting on my genset - which they also didn't fix).

The generator cover was not snapped on, the breakers under the cover were off. The light switch in the reefer was disassembled and in pieces when i got it back. The summer switch was in the "off" position, the "turn switch on when ambient is above 50°" switch was off (it's 90° outside). But other than that, they did a great job.

[JC2]

Quote:

Originally Posted by erkme73 Thanks RVW... I did not fan any fans anywhere under the outside panel... Were the fans possibly an option? FWIW, by the time we made it to Lazy Days, the fins in the reefer were showing pretty significant condensation, and by the end of the four hour wait at their facility, there was ice at the bottom of the fins. They told me there was no way to check pressures, no way to know if the unit was failing internally since they are a sealed unit, and suggested that I buy a new cooling unit for approx $2k. I told him since this was the first time I've experienced any trouble, and it seemed to have cooled by the time we got there, I'd rather wait. Total bill $155 for 1 hr diagnostics (included .5hr for trouble shooting hard starting on my genset - which they also didn't fix). The generator cover was not snapped on, the breakers under the cover were off. The light switch in the reefer was disassembled and in pieces when i got it back. The summer switch was in the "off" position, the "turn switch on when ambient is above 50°" switch was off (it's 90° outside). But other than that, they did a great job.

I don't see anything remotely great about a company that didn't clean up after themselves. Sounds like they just stopped after they found out you weren't going to be sucked into buying a new/rebuilt unit. I sure would go to this link http://www.rvservicereviews.com/ and rate their dismal attempt to please a customer. This will possibly help others steer clear of this place. I would also sent a copy of your review to Lazy Days if they have an E-Mail address.

["007"]

The bouncing around of your refrigerator while traveling will sometimes brake any blockage you may have had with it. I would slip your thermistor down to where it was because its where MFG must have tested for good operating temperatures.
If you see a change you can always move it up.
You should have given a bill back to that dealer with a list just to wake them up, maybe?????
The stickies above show cooling fans that you may add to improve cooling in fresh food compartment during hot weather.

[erkme73]

@JC2 - good idea. I had no clue that Lazy Day's had such poor reviews. I promptly posted my experience. Hopefully others will read them before they use them. Hindsight is 20/20.

@007 - I will do that on my next trip. For now, she's back in storage until end of April. I'll fire up the fridge a full 24 hours before, and move the sensor down to where it was. The OEM left a small blue arrow sticker at the point where it was originally installed.

[Larry3570]

As someone who spends lots of his time helping people repair machines, I have rarely experienced such an annoying contraption as our 14 year old Dometic RM2807 refrigerator. Key to my aggravation is the total randomness of the symptoms. This year, once again, I started everything up pre-trip and as usual the refrigerator wouldn't cool. Of course I tried a day or so on gas, then a day or so on 120V, checked that there was heat, cleaned the chimney, rapped on the tubing, made sure the fans I added were working, tested the door gaskets with paper. No cooling for several days. Then shut it off for cleaning. Upon restarting the freezer came down quickly, but nothing happening in the cooler. Then after about 6 hours the cooler started down. It stayed really cold for about 2 days then suddenly the cooler was room temprature again and the freezer 60F or so. That's where it is now.

I've had this POS out of the wall probably 15 times. It's been cleaned, sworn art repeatedly, the sealant checked, the thermal compound checked, the voltage checked, gas pressure checked, a direct bypass for the 120V heater installed, the hinges and latches adjusted, an entire rebuilt (http://rvicebox.com) cooling unit installed [of course it worked well right after I installed it, but not on the next trip]...you name it!

I probably should just junk the thing, but getting one to fit with an ice maker as we now have is very pricey as only the "top of the line" models have that; plus I'm stubborn and I just don't get what is going wrong with this nasty pile of crap.

Most of the time we put dry ice in it...makes a lovely icebox.

I hear a continual quiet "boiling noise" from the absorber tank, so something's going on in there. I've thought of putting a huge squirrel cage fan in; but this was originally built with no fan...and I have a 6" muffin fan already.

I've moved the thermocouple so many times I'm surprised it hasn't worn through the cooling fin. But that's actually worthless because when I hot wire the 120V element it removes the whole control system from the equation and still there's no reliable cold. Driving or parked, high altitude or low, high ambient tempratures or low...no matter what there's no predicting what this poop heap is going to do!

Thanks for letting me vent. Any solid ideas will be appreciated. We're off on a 3 week, 6,000 mil trip in 3 days.

[RV Wizard]

Larry, You have a restriction in the cooling unit. It is probably a flake of sodium chromate or rust that is blocking a port in the system. This can be caused by several scenarios. Operating the unit off level, too high of BTU heat source or even prolonged operation without proper refrigerant circulation or good air flow across condenser.
You say that the cooling unit has been replaced. Did you replace it or did you have a service center do it? Was it a new unit or rebuilt? Did it come with a new heating element? Did it come with a new baffle? Have you checked the working pressure of the LP gas regulator? Did you buy the coach new or was it previously owned?
The only way to repair your problem is with a new or rebuilt cooling unit making sure that what is causing the cooling unit failures is resolved before operation is started up.

[erkme73]

So there is no product or service that can tap into the cooling circuit and add a 'clot filter' like they do for patience with DVTs or bone surgeries? Seems like there would be a big market.

It reminds me of not that long ago when the dealer (and many others) said the dual pane windows MUST be replaced and cannot be repaired if seal breaks and they become fogged/etched. Yet today there are companies that cater specifically to this type of work. I'm don't understand the absorption cooling system enough to appreciate the challenge, I'm sure. Just seems like someone (much smarter than me) should be able to figure out a way to service the 'sealed' portion of the system...

[Larry3570]

Mike,

Thanks for your reply. Here are answers to your questions:

It was a rebuilt cooling unit from http://rvicebox.com . I put it in myself, however I am a technician who works on similar kinds of things, so I'm confident I did a decent job. I re-used both the gas burner and 120 V element. If by baffle you bean the spiral twisted sheet metal in the chimney, I re-used it. There was no apparent damage to it. The pressure was tested a year or so ago one time I took it to a service center (so far none of the service people have given me any solid "this WILL fix it" info other than "buy a new one".) I am the second owner of the coach.

Since replacing the cooling unit I have been extra careful about keeping the rig level whenever the reefer is in operation. The gas burner gives a nice blue flame. The problem seems identical whether running on 120 V or LPG. I just looked at the reefer, freezer is -10F, cooler is 54F, ambient is 78F, currently there is no food in freezer or cooler.

Wouldn't a flake eventually move to some location where iut wouldn't block the system, or break up? Would tapping the pipes with a rubber mallet help break it up? Would a larger fan help (BTW, the pipes are right against the back wall of the reefer cavity so no air is bypassing them)?

[RV Wizard]

Larry, If you have ever heard of burping a cooing unit; where it is turned on it side, then upside down, then the other side over a period of a couple days. This can dislodge the restriction and the cooling unit MAY return to proper operation. The only problem is there is no guarantee that in time it will get restricted again. It may last years, months, a week or not at all. Once sodium chromate solidifies, it will not dissolve in the cooling unit.