> [TELECOM Digest Editor's Note: A water cooler with a DC motor is
>> interesting; but did you ever see a _refrigerator_ powered by -gas-
>> rather than -electricity-? I had one of those in a long since for-
>> gotten apartment in Chicago back in the 1960's. No motor of course, no
>> compressor, etc, but it was a refrigerator, freezer, etc, and I think
>> (cannot remember for sure) it was manufactured by 'Frigidaire
>> Company'. Totally silent of course. I have no idea how it worked; if
>> I ever knew, I have since forgotten. PAT]
> My mother had one of those, probably in the early 50s. When it was
> replaced by a more modern unit, it was moved to the back porch and used in
> the summer to cool melons and stuff. I guess this was high tech for the
> back porch -- the neighbors had an ice box on theirs for similar uses.
> I think those were ammonia-water absorption cycle refrigerators. I
> seem to recall its making little gurgling noises from time to time.
The refrigerators in RVs are pretty much all of the absorption type. This allows them to work on propane, away from commercial electric power. When commercial power is available, it is used only as a heat source instead of the propane. No compressors or other moving parts. The 12VDC system in the RV is used to ignite the propane (so it doesn't need a pilot), but otherwise, it does not require any electricity.