[TomGuy]

Happens every time. I crank up the heat in my home, lay the ice trays next to the heat outlet, and within 10 minutes, I have ice.

You jest.

But I remember when I was about 8 years old in the mid-1950s, we visited some relatives in a NM. They had a 'gas' refrigerator. I recall looking underneath, as the appliance had about 9" legs, and marveled at seeing the pilot light flickering and wondering how that translated in cold to preserve food.

It looked something like this, IIRC:

[Ditter]

Some former neighbors of mine had a gas air conditioning unit. It required electricity to operate too but mainly it ran on natural gas. I wish I had one, don’t know if it is even possible any more, the electric company has their hooks into us now.

I remember the refrigerator you posted, I remember when we had one but I didn’t know they ran on gas.

[biff]

RV’s today use the same principle in their refrigerators only there is generally 3 ways to run them. 110 volt AC current, 12 volt DC current and propane. Propane is the same principle as your pictured fridge. A small pilot size flame is all that is needed and it changes the refrigerant from a liquid to a gas which is where the cooling effect takes place. Instead of R-22 freon it uses amonia, very corrosive and is generally the reason you don’t see house size AC anymore. The units for houses were quite large to provide enough cooling for a house also.

Decades ago the local gas companies tried marketing the units but gave up because of size and corrosive amonia.

[5thGenTexan]

Probably similar to the technology in a electric/propane fridge in an RV.