Solar water heater incorporating heat pipe

Claim 1

A solar water heater comprising: a platelike heat pipe having a working fluid enclosed therein, the heat pipe including a heat collector having parallel tubular portions and a radiator having hollow portions in communication with the tubular portions; and a hot water tank comprising a synthetic resin main body and a metal bottom plate, said hot water tank being placed on the radiator of the heat pipe, the heat pipe having a collector to radiator surface area ratio of from 3/2 to 9/1, the collector tubular portions being 10 to 500 mm in pitch, each of the tubular portions being 5 to 150 mm 2 in cross sectional area, the main body of the hot water tank having an outer projecting at a lower edge of a peripheral wall, the bottom plate being formed along a peripheral edge with a groove defined by an inside wall, a bottom wall and an outside wall, a sealant, flowable when not cured, being applied to an inside of the groove at least at a corner between the inside wall and the bottom wall, the lower edge of the main body peripheral wall being fitted in the groove with a packing placed between the bottom wall and the lower edge, an upper edge of the outside wall being folded inward in pressing contact with the outer projection, the sealant filling up a clearance between the inside wall and the lower edge of the main body peripheral wall.