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Take a good look at these two pictures. This is the same identical refrigerator but only one day
later, after the black metal parts were cleaned of the surface rust and a new coat of paint applied.
OK, what's so important about having a nice black shiny paint job on the parts of the
refrigerator that you don't even see? These parts are painted black for a reason: heat transfer.
Technically, your refrigerator makes things cool by first heating up some of its parts. After
some magic is done with the ammonia gas to create the cooling inside the refrigerator, these
black painted parts must now shed some of that heat. Take a look towards the top of the
refrigerator and notice one tube with a bunch of cooling fins on it just like a radiator. Metal
finishes that are smooth and black will transfer away more heat energy than a metal finish that
is rusty and covered with dirt.
