Abstract: A solar collector has a liquid system independent of a household hot water heater system, the two systems transferring heat in a heat exchanger. The heat exchanger has an open top inner tank enclosed in a closed outer tank, a coil connected to the hot water tank system circulates under main pressure in a coil in the annular space between the inner and outer tanks. Liquid from the collector enters at the bottom of the annular space, flows upward around the coil and overflows the top of the inner tank. A pump draws liquid from the bottom of the inner tank for circulation through the solar collector system. The liquid in the collector system drains by gravity into the inner tank at any time that the collector circulating pump is not operating, thus providing freeze protection during all normal operations and also at such time that a power failure may occur.

Abstract: The solar-exposed cover portion of conventional solar panel boxes are subject to variation depending upon customer choice, cost, heat insulation requirements and other factors, whereas the interiors of the boxes are standard. Thus, the cover portion may be a panel of plastic, or glass, or a combination of glass and plastic of varying thicknesses. The interior has a thick bed of insulation, headers and tubes all surrounded by a frame. Two different retainers are provided which may be attached around the side edges of the frame and used individually or in combination to accommodate plastic panels, glass or a combination of glass and plastic sheeting. The connecting pipes from the headers to the exterior of the box are provided with seals. By removing the retainers, seals and glass and/or plastic, the headers and tubes may be lifted out of the box for repair or replacement without removing the box.

Abstract: A solar heat collector panel comprising a flat spiral coil of pipe (preferably plastic) having an inlet at the inside and outlet at the outside, the inlet conduit extending out behind the coil. A plurality of approximately radial ribs is attached behind the coil to support the coil spaced from the surface on which it is installed to create a dead air space, prevent dry rot of the supporting surface, hold the coil level and stiffen the panel. A sheet of plastic material is caused to adhere to the back of the coil by adhesive and vacuum molding. The method of fabricating the panel is described in detail. This invention is an improvement on U.S. Pat. No. 4,014,314.

Abstract: A collector panel for thermal energy emanating from the sun comprises a coiled length of tubing arranged in a planar toroid and held in that position by a plurality of radial clamps. The tubing is continuous and carries the fluid to be heated, typically water from a swimming pool or similar container, in a spiral path in the plane of the collector. The collector is inclined at an angle to the vertical, orthogonal to the mean incidence of sunshine at the location of installation.