Inside the bottom of the fridge, place a wide, flat, copper or stainless steel water tank with two pipe connections. Flexible, insulated hoses pass out through two notches cut into the bottom door seal. They pass into an insulated drawer below the fridge, and connect to another water tank attached to the lid of the drawer. When the drawer is pulled forward, the lid swings open, hinged at the rear.

Water in the upper tank is cooled by the refrigerator, and sinks into the lower tank, forcing the warmer and lighter water to rise into the refrigerated tank. ie: a thermosyphon cycle begins.

The lower drawer can be used as short-term cold storage for guests, for bargain bulk purchases of perishables, etc.

The drawer need not be even a permanent fixture, or directly below the fridge. It could be as simple as a disposable expanded polystyrene vegetable box, a cooler bag, a folding insulated box, or a drinks cooler. As long as the tank in the fridge is higher than the one in the extender, a thermosyphon loop is made possible.

Any kind of watertight container can be used for the upper and lower heat exchangers (tanks) - I suggested wide, flat and metal for the greatest heat exchange. Coiled or folded copper pipe is another possibility.

Yes, this will make your fridge work harder: it's not meant as a permanent solution. Keep the thermostat above its minimum temperature setting to allow for the extra work.
-- BunsenHoneydew, Feb 08 2009

Fridge Belly fridge_20belly
diy version [xenzag, Feb 08 2009]

[+] I suggest adding a spigot for simple cold water.

[marked-for-tagline] "can be used as short-term cold storage for guests"
-- FlyingToaster, Feb 08 2009


Cheers, [FT]. I should have picked up that grammatical ambiguity.

And thanks for the link [xenzag] - didn't spot that one in my search. Mine's intended to be DIY as well, but I think it differs enough in the implementation to leave up.

The simplest DIY version could be little more than two PET bottles, some auto or garden hose and hose clamps, and a shopping cooler bag.

The permanently installed version is meant to be craftsman installed - for example when doing a kitchen remodel.
-- BunsenHoneydew, Feb 08 2009



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