A syphon, as any elementary science student and efficient gasoline thief knows, is a tube that transports liquid up and out of a container at one level to a second container at a lower level — all with the help of atmospheric pressure. As kids we made syphons just by sucking air out of a […]

Natural circulation solar hot water systems — thermosyphon systems, to use the more techni­cal term —’ have a lot of appeal for households that don’t need very much hot water. We’ve touched on these a bit already. The real beauty of a free-circulating system is that it operates with no fuel or power costs — […]

Don’t use ordinary — and poisonous — automo­tive antifreeze. The very best antifreeze for solar collectors is something called "non-toxic propy­lene glycol." You should be able to find it in any plumbing supply store. If not, order Sansol 60 from Sunworks, Box 1004, Mew Haven, Connect­icut 06508. (Also see appendix.) Five gallons should be more […]

Connections between pieces of copper tubing are made with special fittings and solder, as everyone knows. Plumbers, fix-it men and do-it – yourselfers call it "sweating" joints. Copper pipe, of course, is soft and easy to cut. You can use either a hacksaw or a small tube cutter which leaves you with a perfectly square […]

TABLE 10 NOMINAL DIMENSIONS FOR TYPE L COPPER TUBING Nominal Outside Inside Size Diameter Diameter Va" 0.375” 0.315” W 0.500” 0.430” Vz" 0.625" 0.545” W 0.750” 0.666” W 0.875” 0.785” 1” 1.125” 1.025” V/a" 1.375” 1.265” V/z" 1.625” 1.505” 2" 2.125” 1.985” Courtesy George Daniels, Home Guide to Plumbing, Heating and Air Conditioning. Table 10. […]

The energy transfer system in a solar water heat­er is nothing more than good old fashioned plumbing. We move heat energy from the source (the absorber plate in the collector) to the storage area (the hot water tank) through pipes. This transfer system may be regulated in some cases by a control system, which usually […]

Keeping heat in a hot water storage tank is like trying to keep a leaky inner tube pumped up. No matter how hard you try, you’re constantly fight­ing a losing battle. Some heat will always escape. How much insulation is enough? It’s theoreti­cally impossible to over-insulate a solar hot water system, but here are some […]

Water tanks are heavy. The water alone in a 120-gallon tank weighs about half a ton. (A cubic foot of water weighs 62.5 pounds, and there are just a touch over 7.5 gallons to the cubic foot.) Naturally it would be dangerous to put a large tank in an attic or on some wooden floor […]