[anenefan]

Up until the 80s such principals were touched on in senior school classes of chemistry and physics. While I would assume most people in my locale once having a strong agricultural connection and can do attitude to fix things, have understood gas compression heat exchange, few would have understood the old kero / gas (heat) powered fridges worked precisely.

Present times I would not like to guess how the population around would fare - when I see weather disasters the last few years, many are throwing their fridge out once it's been flooded - rather than take a couple of weeks to clean and wait for it to dry out. Sure they've become very complicated and some brands don't respond very well to being saturated, the guts of the compressor are sealed.

Most of what I learned about fridges I did during a few months as a delivery person working for a white goods company.