MORE WAYS TO RECYCLE OLD REFRIGERATORS INTO LOW COST SOLAR WATER HEATERS

Enlarge Image Image Gallery Below: Dennis Burkholder displays the Hotpoint door and heat excharger which fit together so well to form a flat-plat solar collector panel... the door with its interior lining ? but not its insulation ? removed and the exchanger ready to go into place . . . and the two put together. SECOND ROW: The first of two panes of glass has been cut to fit under the rubber gasket around the edge of the refrigerator door and is now seated in a bead of silicone as Dennis prepares to mount the second sheet of glass ... the nearly completed collector clear show copper tubing has been run through an end wall of the refrigerator door to connect the solar panel to a storage tank and other parts off active water heating system ... the completed installation.

When Miles K. Free III sent us an article telling how he'd recycled an old refrigerator into part of a solar water heating system (see "Recycle a Refrigerator Into a Solar Water Heater", pages 108—109, MOTHER NO. 48) ... he didn't know that MOTHER's researchers had already been working on the same idea for some time.

Whereas Miles began his project by thinking about how easy it'd be to convert a refrigerator into an insulated storage cabinet for a tank of solar-heated water, however, MOTHER's research staff sorta approached their conversion project "the other end to".

It all began with an old junked Hotpoint refrigerator that a couple of MOTHER's people were taking apart with the idea of using its compressor as a small solar-powered steam engine or something of that nature. Almost immediately, though, the experimenters were speculating about the heat exchange coils on the back of the reefer's cabinet.

"Hey, that looks an awful lot like the serpentine tubing which goes inside a flat-plate solar collector."

"Yeah, except that the diameter of this stuff—it looks like it's about a quarter inch—is so much smaller than the diameter of the tubing—about a half inch—generally used in a collector."

"Yeah ... but I betcha this exchanger will work in a flat-plate. It may not work as efficiently as a heat exchanger custom-made of bigger tubing, but I think it'll still work. And if it does ... heck, the price is surely right."

So our intrepid adventurers forgot all about their steam engine project and began looking for an insulated collector box to mount their prefabbed heat exchanger in. Just then their eyes fell on the old Hotpoint's front door.

"Hot dog. Look at this. All we've got to do is take the plastic liner out of this door and the exchanger will fit right in. We've already got two-thirds of our whole flatplate collector built for us ... and we haven't even picked up a hammer yet."

What the boys were crowing about was the fact that whoever had originally designed that trusty old Hotpoint ... couldn't have done a better job of making the fridge easy to recycle into a flatplate solar collector. On the one hand, the reefer's heat exchanger—a nearly flat sheet of steel with a serpentine length of tubing already welded to it looked (except for the fact that its tubing was small) just one heck of a lot like the heat exchangers in some very expensive solar collectors. And on the other, the fridge's door—which was really a shallow steel box that was already well insulated—made as nearly an Ideal flat-plate collector box as if it had actually been planned for that end use.