Refrigerant Question

[dcscott]

We recently purchased a used fiver off of a dealer lot. I’ve noticed that after it has been sitting for a few days with the fridge running, that when I open the fridge door there is a very strong ammonia odor. I know that years ago ammonia was used as a refrigerant but thought that with the invention of Freon, and subsequent ozone friendly products, ammonia was not used anymore.



Does anyone know if ammonia is still used in an RV fridge?



I’m thinking that perhaps the dealer knew that the unit would not hold Freon and substituted ammonia instead. Kind of like the old trick of putting water in a automobile radiator that had a very small leak that wouldn’t hold antifreeze but would hold water.

 

[B.G. Smith]

Refrigerant

As far as I know, all the refrigerators use a n ammonia mix. You can buy a rebuilt unit for about 2/3rd the price of a new unit but I have heard they don't last long. bg

 

[Bill Stockard]

dcscott,

Welcome to the world of finicky, slow cooling, high maintenance, absorption type RV fridges!



Here's a web site where you can learn all about absorption type fridges with tips on how to diagnose problems and repair them. Also there is a forum where you can ask questions and get honest answers.



http://www.rvmobile.com/



What you have is a failed cooling system. The ammonia and hydrogen under pressure is the refrigerant. I imagine the piping in the evaporator area has rusted through from condensation (moisture) on the steel lines. To get the fridge cooling again, will require the fridge to be removed and either a new or rebuilt cooling unit installed. Been there and done that three times in the last 10 years--twice under the extended warranty and once out of my pocket.



Bill

 

[dcscott]

Thanks you guys. That website was very helpful. Looks like I'll be pulling the cooling unit out soon.



I just had an afterthought. The fiver is 12 years old. Does it make sense to try and rebuild the old fridge or should I simply blow my budget on a new one. The old one is 110V and propane only so perhaps it might make more sense to go to a new 3-way unit. I have a rough idea what that would cost but no clue what a new or rebuilt cooling unit might run for my old unit.

 

[plongson]

I know that they are big bucks, but I would bite the bullet and install a new one. I just bought a new one for $16,000 and they included a trailer at no extra cost ... but really... The new frig's really work good and seem to cool way better than the one in my old '91 Terry...

 

[Bill Stockard]

If your fridge is a Dometic, they make a replacement fridge to fit the opening. Some of the newer models will not fit in the cutout area where the older ones were installed. Be sure to check the size before you buy a replacement.



I wouldn't bother to try to get a 3-way instead of the 2-way. The 12 volt DC element is very inefficient. It draws 16-18 amps. Unless you have at least 8 gauge or preferably 6 gauge wiring from you tow vehicle battery to the fridge in the trailer, the fridge running on 12 volts will only drain your trailer battery and shut off.



I think you would be better off replacing the whole unit if you can afford it. Like posted above, the newer units do a little better job of cooling.



Good luck!



Bill