My Dometic is losing the battle of the bulge

[Lance M]

My '72 Ambassador, Abby, has the original Domestic RM 75a. The doors will not seal because of a bulging piece between the freezer and the refrigerator. It has been getting worse the last month or so. The fridge works well on both gas and electric. The door not sealing causes a lot of condensation.
Has anyone repaired this problem before?

[cutty]

Top, we have the very same model and year camper, same fridge and same problem. So far, our solution is locking the doors shut all the time and it seems to stay sealed. If you find a solution, I'd be glad to hear it. I quit after beating it with a baby sledge with a 2x4 against fridge bulge. The 2x4 gave up first.

[Melody Ranch]

Perfect!
You are going to have to replace it. Bring Abby up here on a week end and we can invite some folks up for a real, hands on, work rally. I'm serious.

[Lance M]

Originally Posted by Melody Ranch

Perfect!
You are going to have to replace it. Bring Abby up here on a week end and we can invite some folks up for a real, hands on, work rally. I'm serious.

Thanks Melody,
I think I can fix it! I'll try at least. I'll give you a ring when I know what is going on this weekend. My Mom and Dad are dragging the '62 GT down from MN. They are leaving on Thursday from MN, so maybe???

[HiHoAgRV]

I had the same problem on my '77...

To describe the fix, first imagine that the problem is the foam in the door panels has continued to expand and has pressed out the abs panels to the point where the door(s) don't fit into the fridge...and thus don't close...

Solution?

Remove part of the foam!

I took apart the door and used a hack saw blade to saw slots into the foam, all the way to the back side of the plastic panels. Fill the slots with some foam glue and shove the door back into the opening with some thin cardboard placed into the slot to help squeeze the door panel back into shape...once the glue dries, reassemble the door...it now fits!

[Lance M]

Thanks for the tip Vernon! On mine it is the main part of the fridge that is bowing outward. Maybe it is hard to see from the pics, but the doors are square and true. I guess I'll have to yank it out and make some adjustments!

Originally Posted by HiHoAgRV

I had the same problem on my '77...

To describe the fix, first imagine that the problem is the foam in the door panels has continued to expand and has pressed out the abs panels to the point where the door(s) don't fit into the fridge...and thus don't close...

Solution?

Remove part of the foam!

I took apart the door and used a hack saw blade to saw slots into the foam, all the way to the back side of the plastic panels. Fill the slots with some foam glue and shove the door back into the opening with some thin cardboard placed into the slot to help squeeze the door panel back into shape...once the glue dries, reassemble the door...it now fits!

[Partridge]

I'm having the same problem...

[Lance M]

We recently returned from our long summer trip. The bulging is getting worse. The freezer was cold as could be, but the fridge was warm. We had some groceries that we had to throw away. I think I better attempt to fix it or put in a new fridge. Having to buy four bags of ice a day and tote around three coolers is a pain! Anyone replaced an RM 75 with a new DM 2820? That is what's listed on the Dometic website as the proper replacement.

[SpaceGhost]

Mine in our '73 got the bulge after firing-it up out of a couple year storage. Same issue, ice cold freezer, cool but not cold fridge ... so a new one for me too.

[3Ms75Argosy]

Top, a couple of ideas? Could you heat the area with a heat gun and hold a 2x4 against it as it cools? Or.. Build another gasket around the door, letting the extra material seal the door where it isn't as thick?

[Lance M]

Well, I took Vernon's methods and applied it to the fridge.

First I took a dremel and cut the metal cap loose on the LH side.


Then I took a knife and cut back some of the bulging foam. I cleaned it up. Applied some Trempro RTV Silicone. I used a piece of cardboard to get the top panel of the fridge compartment to seal.



It is a great thing to have these forums to share knowledge in such a great way. Thank you all for your help and suggestions. I knew it could be fixed! Hopefully in 12 hours the RTV will have set up and sealed everything. I'll let you know how she looks tomorrow.

[Lance M]

Frustrating. Very frustrating. Yesterday morning I went out to the fridge and checked the temp on the thermometer, 68 degrees. I figure, "well it has only been one night of cooling, let me get one of those battery operated fans and see if it helps". Yesterday afternoon I stopped at an RV place and bought one of those battery operated mini fans. I put it in last night and this morning the thermometer read 60 degrees. Now granted it was VERY hot yesterday, like 108. It must have been at least 120 inside the trailer yesterday evening. But 60 degrees in the fridge isn't going to get it. I guess my next step is to get those little cooling fans for the back of the fridge.

[memgrove2000]

Top, Dump it and install the 2820. We did it to ours last week. I picked the fridge up at noon on thursday then I worked until 3:30. Home by 4:00 Fridge installed and cooling by 9:30. Food in Friday at 7:00 am and camping by 3:00 friday afternoon. The only real pain was running the 12 volt in from the bathroom under the bed then behind the pantry.

The light in the new fridge makes my wife smile.
Not having to push the new door shut with my foot makes me smile.

[Lance M]

Well an update of sorts, we went to the gulf this past weekend. The fridge would not go below 60 on gas. The freezer was working pretty well. It was about 5 degrees when I checked it. I switched to electric at the campground and the fridge got down to 40 degrees in about two hours. I think the burner/chimney needs a good cleaning. I'm not looking to drop a thousand on a new fridge just yet. Suggestions?

[Pahaska]

Originally Posted by Top

I switched to electric at the campground and the fridge got down to 40 degrees in about two hours. I think the burner/chimney needs a good cleaning. I'm not looking to drop a thousand on a new fridge just yet. Suggestions?

Buy, beg, or borrow a manometer and check the propane pressure at the test port at the burner. I had the same problem of cold freezer and warm lower section on propane but great operation on AC. I found that instead of the specified 11" of pressure at the burner, I had just 8" at the test port. Adjusting the regulator fixed my problem and it is now just as cold on propane as on AC. Any RV place can check the pressure in minutes.

The springs in the regulators weaken as they age and the pressure drops gradually over time.

[Lance M]

Thanks for the suggestion Pahaska! I took your advice and bought a monometer from the local propane and propane accessories store, Smith and Smith Propane in Killeen. Vintage Trailer Supply has the same low pressure test kit on sale for $30. I paid a little more than twice that, but I needed it right now.
I referenced the manual for old Dometic fridges and hooked up the manometer to the test port. With the temp selector on "MAX" it read 4" not the required 11". Problem found. Now to fix it.
I tried to adjust the thermostat "Cold Adjustment" screw. It didn't change the pressure at all. I figured that I must have some gunk in the propane line somewhere. Sure enough I found a big old plug of unknown substance inside the line to the fridge. I cleaned it all out and re installed it looking for the magic 11". I was disappointed to see 4" again. This time I took the gas thermostat off completely and checked the pressure at the gas valve for the fridge. 4" there as well.
I then turned my attention to the pressure regulator at the tanks. I disconnected the outlet line from the regulator and checked it there. It was reading 10". Since I read in the service manual how to adjust the regulator I adjusted it up to 11". I know I know, all you doomsdayers are thinking I'm going to blow myself up about now, but I watch McGuyver when I was a kid so it's cool.
I narrowed it down to line blockage between the regulator and the Tee for the fridge supply line. I took the line off and flushed it with alcohol and blew it out with compressed air. Some more chunks of I don't know what came out. I reinstalled all the propane lines and did a leak check with soapy water. I hooked up the manometer to the test port and it was at 11".
The only major problem is that while I was trying to adjust the thermostat with a blocked propane line I unscrewed the adjustment screw too much and the spring came undone. This caused the outer stamped portion of the thermostat to fall off from the other portion of the thermostat body. I now need a new thermostat for real! Luckily Dometic has them on the shelf for $120.
Since the thermostat is toast, I took the little spring and valve from the inside of the thermostat and now it is on "Max" all the time. It was 100 degrees when I closed the door to the fridge. We'll see what the thermometer says in the morning.

[Lance M]

So after firing the fridge up yesterday the starting temp was over 100 degrees. This morning the thermometer read 48 degrees. I think I'll get one of those 12v DC fans from Radio Shack and make some duct work to get a little more air moving on hot days. I'll do it all at once after the new thermostat arrives.

[Inland RV Center, In]

Originally Posted by Top

So after firing the fridge up yesterday the starting temp was over 100 degrees. This morning the thermometer read 48 degrees. I think I'll get one of those 12v DC fans from Radio Shack and make some duct work to get a little more air moving on hot days. I'll do it all at once after the new thermostat arrives.

Clean the reefer flue and especially the burner orifice.

All reefer burner orifices must be cleaned periodically, as they slowly partially plug up.

Taking the orifice out and placing it in "limeaway" for a couple of days, does the trick.

Andy

[Lance M]

Thanks for the suggestion Andy. I'll add those items to the list of things to do.

[Trex]

Place a fan behind the fridge, Mr. Top...it will help cool down your old fridge. The origninal fan had a thermostat on it, so it would turn-on when there is to much heat behind the fridge....but make sure you put a on/off switch inline. There will be times when you will want to turn the fan off, because of the noise level.