re: Why did our ancestors put the freezer on top of the refrigerator?

top freezers are way more reliable, last loner, have almost no ice maker issues.

The bottom freezer units with icemakers in the fridge are almost universally disasters. If you own a LG get some KY jelly ready.

My freezer is in the back of the refrigerator.

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Heat rises, so one would assume the natural order is to freeze the bottom and as the temp surpasses 32 it would help maintain refrigeration above, so there has to be some obvious reason why freezers were put on top, counterintuitive to the obvious.

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It’s not really counterintuitive. You just have the “intuitive” answer backwards.

Warm air rises and cold air falls. Which means you want the cold air to enter the refrigerator (or freezer) compartment at the top. That way, the natural convection helps to maintain uniform temperature throughout the compartment. If cold air enters at the bottom, then the bottom of the compartment ends up being much colder than the top.

Even with the naturally rising warm air & falling cold air, in practice the areas closest to the evaporator coils (at the top) still stay the coldest. Consequently, old school refrigerators had a single compressor and a single evaporator, located in the freezer compartment. The thermostat would be located in the refrigerator, and cold air would migrate down from the freezer. The freezer naturally stayed colder, but it wasn’t really controlled. The freezer had to be mounted at the top in order to stay cold enough.

Then designs started changing to two thermostats but still one evaporator. The freezer thermostat would control the compressor/evaporator, and the refrigerator thermostat would control air flow from the freezer compartment to the refrigerator. This allowed the freezer temperature to be controlled, but still required a top-mount freezer.

Newer units have multiple evaporators so that the refrigerator and freezer can be completely isolated from each other. In some cases there is one compressor that switches between the two evaporators depending on what needs to be cooled. In other cases there are separate dedicated compressors for the refrigerator and freezer. Either of these configurations basically eliminate the need to top-mount the freezer, though top-mounted freezers are still generally more energy efficient.

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Anyone know the actual reason?

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Because heat rises. Keep the top frozen and us the falling cool air to "cool" but not freeze the bottom.

That's my nonscientific guess.

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The bottom freezer units with icemakers in the fridge are almost universally disasters.

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Lol. I’ll let some subzero owners that I know, know this. Their fridge is going on 22 years now. I’m sure it’s going to break down any day now.

I have one of these old school ice boxes. I assume the coldest compartment is the top left as it has a lot of insulation in that door.

We used it as kids to store books and toys.



Maybe I’ll have a garage sale so antiquetiger can buy it and post it here.

In my experience as someone that owns a bottom freezer, it was probably to keep the fricking toddlers out of the frozen stuff. Little bastards treat it like a buffet of popsicles and ice cream.

Our 45 year old GE Refrig has the freezer on top and still works just fine.

Great explanation.

It bugs me so bad. That some brands you have to solder and vac the system to replace the refrigerant valve. Others have a magnetic external switch you change.
I actually hate 2 evaporator units. Just because harder to work on. Better for customer. Two compressor units are the best but not that common. Sub zero used to be the only one. Most other high end units like Monogram, viking and Thermador use just one compressor.