Gramps has one in our hunting cabin and it has worked for over two decades (has been in the cabin for 20 years, I don't know where it was at before then). My question is, how do they work? All these years never really thought about it till now. Someone help me learn something today...

 

the ng/lp refers used a flame to heat the freon which expanded and compressed the gas which circulated thru convection(real simple explanation).
Clark

 

Hydrogen gas and an ammonia-water solution is used in gas fired refrigerators not freon. They do indeed last and work great. Goodluck,,Rick

 

Makes sence. So there is a flame under there somewhere?

 

Yes, which heats the liquid and turns it into a gas, similar to the evaporator in a A/C or normal refrigerator. Then that gas goes througha condensor, makes the food cold, then does the cycle again.

 

This type of cooling is called "absorption" and uses most any form of heat to move the fluid/gas around the coils without any pumping. They have been around for eons. When I was a kid being raised in the boondocks of Arkansas, we had a refrigerator that had a kerosene burner.

The pipe supports that hold the crude oil lines in Alaska do exactly the same thing. Except in this case, heat from the hot oil drives the fluid in a way as to keep the ground frozen to prevent melting the permafrost.

Many industrial plants use excess steam to drive absorption units to refrigerate or cool other processes. The original ice plants and cold storage units used absorption units to make ice.

 

RV refig's come to mind. Same principal I would think.

 

If you've got an old one, (like an old LPG powered Servel) for the hunting cabin or such, do yourself a favor, get a carbon monoxide gas alarm like is sold just about everywhere now..
They, just like any gas powered appliance,(space heater, hotwater heater etc) the gas/air mixer can get dirty/clogged up and the burner flame can begin emitting CO into the living space of the house or cabin. I've read of CO deaths at hunting cabins due to the LP 'fridge pumping out CO... Just cheap insurance...

Don't let that scare you though... Those old things last almost forever.
Your grandkids will probably be using the thing one of these years...
They work well, and are equipped with LOTS of insulation in the walls of the thing.
There are companies out there that rebuild/remanufacture ammonia absorbtion sealed systems for just about all the RV 'friges out there.
I expect there is someone out there that supports the old Servel's too.

K.

 

That's deffinetly good advice and cheap insurance. The cabin is not airtight by far, could quite possibly be why i'm still alive. Most would call it a crude structure at best, it may block 80 percent of the wind on a good day, but she does atleast keep us dry and serves the purpose.

 

The Amish around me use a lot of them and they last a long time , why they are so hard to find and why someone doesn't come out with a new improved model is beyond me . I have seen a unit they have that runs on kerosene also but they have cost a few homes around here when a sleepy Amish accidentally fills them with gasoline . What I really can't figure out is why they aren't making whole house air conditioners using the same method . I have been looking at a lot of places bye me that come with free gas and I would think their would be a large demand for a unit like that .

 

Ill bet it is a Servel..
There were a lot of them in use back in the 30's, 40's and into the early 60's, most of the old houses have a gas line behind the refrigerator.
Leak detection on the system was easy, can't miss that smell of ammonia
Burns your eyes.

http://www.gasrefrigerators.com/howitworks.htm

http://www.gasrefrigerators.com/faq.htm#fail
Jim

 

Yes, same principal. Most modern RV refers can switch from a 110V or 12V heating element to the LP flame. Basicly anything to heat the ammonia solution is all that's needed.

 

i have read that the bigger gas cooling units are not very economical when cooling something as big a a home.

 

It is funny how they became extinct...

Servell Developed the first frost free refigerator... Ammana Wanted the patent so they bought servell so there went the sevell name...

To be frost free you need a motor to blow the cold air into the frige. That ment that you needed both a gas connection and a electrical connection. Builders started building houses with just electrical behind the frige so they stopped making gas/ electric friges..