Dometic rm2510 absorption fridge conversion to 12v compressor

[TouringDan]

We have owned our 66 Tradewind since 2009. It originally had the model 52 Dometic fridge. It worked ok on electricity but I could never get it to work on propane. I stumbled across a Dometic RM2500 (1984 age) that hadn’t been used much and installed it. It worked on electric and propane but sometimes wouldn’t cool adequately and never cooled very well in hot weather. Access to work on it was extremely difficult so I decided to replace it with a new RM2510 in 2013. I figured by buying a new fridge my fridge problems would be behind me. Not so. It generally works just ok but can’t seem to consistently keep the fridge temperature below 40F and never cools adequately while we are traveling or in hot weather. Again access to perform any maintenance is very difficult so we have made the decision to convert it to a compressor fridge.

I would like to ask if any other Airstream owners have converted a Dometic 52/RM2500/2510 absorption fridge to a compressor fridge?

[Al and Missy]

I got my replacement cooling unit from JC Refrigeration.
https://jc-refrigeration.com/

They don't list a replacement for the 2510 but it might be worth a phone call.

Have you looked into the Vitrifrigo line? I think Switzi put in one of thier 5 c.f. units.

My unit now has a fan on the back that supposedly helps the efficiency. The instructions for installation of my 8 c.f unit say to keep dead air space around the unit to less that 1.5". There is a huge dead space above my unit and I think the fan creates eddy currents in there that reduce the efficiency of the freezer cooling.

Al

[TouringDan]

Originally Posted by Al and Missy

I got my replacement cooling unit from JC Refrigeration.
https://jc-refrigeration.com/

They don't list a replacement for the 2510 but it might be worth a phone call.

Have you looked into the Vitrifrigo line? I think Switzi put in one of thier 5 c.f. units.

My unit now has a fan on the back that supposedly helps the efficiency. The instructions for installation of my 8 c.f unit say to keep dead air space around the unit to less that 1.5". There is a huge dead space above my unit and I think the fan creates eddy currents in there that reduce the efficiency of the freezer cooling.

Al

Al

Thanks for your input. Did you install a replacement fridge or did you convert your absorption fridge to a compressor fridge?

[Al and Missy]

Originally Posted by TouringDan

Al

Thanks for your input. Did you install a replacement fridge or did you convert your absorption fridge to a compressor fridge?

I installed a replacement 2-way unit, but JC makes 2-way cooling units and 12V conversion units. I looked but they don't list one for your fridge, It might still be worth a phone call.

[TouringDan]

Originally Posted by Al and Missy

I installed a replacement 2-way unit, but JC makes 2-way cooling units and 12V conversion units. I looked but they don't list one for your fridge, It might still be worth a phone call.

Al

I originally planned on installing a replacement compressor fridge, but nobody seems to make one that fits well and I have decided that I want to convert the existing fridge to a compressor fridge.

Dan

[TouringDan]

Here is a photo of the 2013 RM2510 absorption fridge installed in our 1966 Tradewind and the extremely limited access for any maintenance/repairs that might be required.

Dan

[TouringDan]

[Boxite]

Could someone post some links or other contact info for whoever makes conversions and/or replacment units for Dometics..? Thx.

[uncle_bob]

Hi

The guts of an absorption fridge are *very* different than the guts of a compressor fridge. Doing a "conversion" (as opposed to a replacement) would be very involved. Pretty much nothing other than the door / hinges and outer cabinet would be retained after the conversion.

Bob

[TouringDan]

Originally Posted by Boxite

Could someone post some links or other contact info for whoever makes conversions and/or replacment units for Dometics..? Thx.

Boxite

Here is a listing of the conversion units made by Isotherm.I am planning on using #2012 for our conversion. Here is a description of the conversion equipment.

Dan

[TouringDan]

[TouringDan]

I tried to find a good replacement for the RM2510 and basically didn’t find anything that looked like a good fit to me. I then visited Bubba L a couple years ago and saw the beautiful job that he and Stephanie did converting the original fridge in their 55 Flying Cloud to a compressor fridge. Here are photos.

[TouringDan]

After seeing their conversion I decided that I really didn’t want a replacement fridge but wanted to convert my Dometic RM2510 to a compressor fridge. I like the fact that the fridge box will be completely built in and can be very well insulated. The compressor and thermostat will be installed in the wall cabinet above the fridge. It needs to be in an area that can be ventilated. This is no problem at all because this is exactly where the roof vent for the fridge is already located.

[TouringDan]

Here is a photo of where I intend to install the compressor fridge equipment. I like that the area can be well ventilated and there is easy access to repair any of the equipment.

Dan

[TouringDan]

Originally Posted by uncle_bob

Hi

The guts of an absorption fridge are *very* different than the guts of a compressor fridge. Doing a "conversion" (as opposed to a replacement) would be very involved. Pretty much nothing other than the door / hinges and outer cabinet would be retained after the conversion.

Bob

Bob

I agree that conversion will definitely be more involved. I also believe that it will result in a better fridge. I am planning on moving the rear wall of the fridge back about 3” after I remove all the absorption stuff. This may be extremely difficult to do and I am not sure how well it will work out. This is my plan though. I am hoping that if I am able to do this I may be able to increase the fridge size from 5 cubic feet to 6 cubic feet. The other huge benefit is that the compressor fridge equipment will be well ventilated and will have easy access for repair.

Dan

[uncle_bob]

Hi

I'd suggest buying a compressor fridge and tearing it apart for the components. The gotcha there is that some of the stuff in a typical modern fridge is non-reusable / non-repairable. They weld them together at the factory and that's it. A lot of what you once ( 50 years ago ) could get at is no longer there.

Since you have to rip out all the pipes and insulation, getting this or that to fit is unlikely. You are now off to bending the piping and designing how it fits. Just how you fab a new inner shell ... yikes .....

Since there is a *lot* of difference between various designs and much of that is in the software, buying bits and pieces would depend a lot on your background in embedded systems programming. There's also likely some advanced physics to dig into.

Given the modest gain in cost from keeping the old shell, and near zero market, I very much doubt you will find somebody who makes something that drops into the old shell. Unless you can find a compressor unit that fits the hole, it's time to modify the hole ... sorry about that.

Bob

[TouringDan]

Originally Posted by uncle_bob

Hi

I'd suggest buying a compressor fridge and tearing it apart for the components. The gotcha there is that some of the stuff in a typical modern fridge is non-reusable / non-repairable. They weld them together at the factory and that's it. A lot of what you once ( 50 years ago ) could get at is no longer there.

Since you have to rip out all the pipes and insulation, getting this or that to fit is unlikely. You are now off to bending the piping and designing how it fits. Just how you fab a new inner shell ... yikes .....

Since there is a *lot* of difference between various designs and much of that is in the software, buying bits and pieces would depend a lot on your background in embedded systems programming. There's also likely some advanced physics to dig into.

Given the modest gain in cost from keeping the old shell, and near zero market, I very much doubt you will find somebody who makes something that drops into the old shell. Unless you can find a compressor unit that fits the hole, it's time to modify the hole ... sorry about that.

Bob

Bob

I am a bit confused by your response. Why would I buy a compressor fridge and tear it apart for the components when Isotherm makes conversion kits in various sixes that are designed to do exactly what I want to do- add compressor cooling to a an existing refrigerator box. Also Bubba L has already used one of their conversion kits to convert their original absorption fridge to a compressor fridge and they are very happy with the results.

There are also plenty of boaters that have used their kits to convert ice boxes to compressor fridges. There are numerous Utube videos. Here is a good one.

Dan

[TouringDan]

The conversion kits are designed to convert an ice box to either a refrigerator or a freezer. As such they only come with one evaporator plate and one thermostat. To cool both the refrigerator section and the freezer section the evaporator plate must extend from the refrigerator section into the freezer section This is really no different than the rm2510 in absorption mode as the thermostat is located in the refrigerator section and the freezer section will just get colder. The only problem is that you don’t know how much evaporator plate you need in the freezer to make sure it gets colder than the refrigerator section.

[Bubba L]

I guess the main difference between the Isotherm conversion oval evaporator and the flat plate evaporator is the oval concentrates the cold within the oval. The flat plate spreads the cold evenly through out. I would think that a freezer with a door has to have the evaporator plate as a common wall for both the freezer and fridge section. Maybe if one of your existing freezer walls was a portion of your evaporator, the freezer should be colder than the fridge compartment if the freezer door were closed. I’m sure you want to maintain the original design of the Dometic. On ours, once we had the t-stat set where we were happy with the temps in the freezer and fridge, we were good to go. I guess on our oval evaporator, the cold is concentrated within the oval keeping the freezer freezing and the open volume of the fridge compartment is cooled by the exposed evaporator. Can you mock something up? The more plate exposure that’s in the freezer, the colder it will get. I just don’t know how you can temporarily place the plate and adjust it. No help.

[TouringDan]

My original plan was to install an Isotherm 2012 with a 32” long evaporator plate. The plate would be installed on the rear vertical wall that is 32.5” high. About 6” of the evaporator plate would be installed on the rear wall of the freezer that is 6” high and the other 26” of the plate would be installed on the back wall of the refrigerator section. Logic tells me that if I did it this way, the freezer and fridge would be at the same temperature.. I am now thinking that I need to install an Isotherm 2017. This has an evaporator plate that is 39” long. 26” of the plate would be installed against the rear wall of the refrigerator section and 13” of the evaporator plate would be installed in the freezer. For this to work the evaporator plate would need to be bent into an L shape at the top. 6“ of the evaporator plate would be against the rear wall and 7” would go along the top in the freezer. I think this would insure that the freezer would be significantly colder than the refrigerator.

Here is a photo of the freezer section.

Dan