Dometic fridge question...

[denmarc]

I've been in rv's most of my life. But have never ran across this issue before. Have an old 1994 Dometic 2-way that has worked great since  new. Camping this weekend and fired it up on LP. Freezer works fine but fridge compartment doesn't! Ideas?

 

[Gary RV_Wizard]

Yeah, the cooling unit has finally died on you.  That's the first symptom of a failure due to a tiny leak in the metal tubing. 

An RV absorption fridge is a two-stage cooler, with the primary stage chilling the freezer and a second stage using the residual from the freezer to chill the main box. When cooling efficiency deteriorates, the fridge part is the first to be affected.  A common cause of that is a pinhole leak that first lets the hydrogen gas component escape. The hydrogen is what makes the second stage work, so the fridge box gets warm. After some further leakage, the freezer will warm up as well.

There is no repairing the cooler - you simply bolt on a replacement. It's literally a bolt-on, DIY-capable job - no solder or compressor or coolant charging to do. 

 

[denmarc]

Thanks, Gary. Just curious, I thought these units are ammonia operated. Where does the hydrogen gas come into play?
Also, your reply sounds to me that a new refer is probably the best thing to do. Due to its overall age.

 

[Rene T]

Thanks, Gary. Just curious, I thought these units are ammonia operated. Where does the hydrogen gas come into play?
Also, your reply sounds to me that a new refer is probably the best thing to do. Due to its overall age.

No what he was saying is that you can purchase just the cooling part of the fridge which is everything on the back. It's a DIY project.  Take the fridge out of the hole and lay it on the floor of the RV. Remove the old and install the new. Keep the same box so it will fit right back into your space.

 

[denmarc]

I get all of that. I'm just wondering if it's worth all the time, money, and effort for a fridge of its age?

 

[John From Detroit]

Thanks, Gary. Just curious, I thought these units are ammonia operated. Where does the hydrogen gas come into play?
Also, your reply sounds to me that a new refer is probably the best thing to do. Due to its overall age.

Ammonia is one of the components in the system Hydrogen and water are also part of the system. and Ammonia is NH3 (That's 3/4 hydrogen by atom count) as well so there is lots of hydrogen in the mix. 

(thinks I really don't need to know but somehow absorbed like the cooling unit absorbs heat).

 

[Madcow]

If one is pulling the fridge anyway, and they are going to keep the trailer for a while, then depending on the size of the unit, Dometic makes true compressor fridge models with the same exterior dimensions so that they are a direct fit replacement.  They use less 12v power than any absorption fridge and can be left on all the time since many only use about 3AH.  A typical solar power battery charger would exceed that.  They also flip to AC when on shore power. 

Nice thing is with the compressor version, there is more interior space available for the same size fridge than an absorption version and cooling is more uniform in both boxes along with much faster cool down after sitting off for a while.  Very similar to residential fridge but built for hard core RV use.