Abstract: A heat exchange interface apparatus for installation between a conventional working fluid unit such as an air conditioner or heat pump and a distribution system such as finned heat exchange tubing installed around the perimeter of a domestic or commercial building. The interface apparatus includes a variable, self adjusting valve which controls and regulates the amount of cooling fluid delivered to the heat exchange tubing in accordance with the temperature of the working fluid at the outlet end of the heat exchange tubing.

Abstract: A heat exchanger comprising a refrigerant tube in coil form leading from the output side of a compressor and a water tube in coil form tapped from a source of water to be heated, the tubes being coiled together so that each coil of the water tube is interposed between a coil of said refrigerant tube, and vice-versa. Inner and outer cylindrical sleeves are disposed within and around the coiled tubes thereby defining an annulus which enhances the heat transfer from said refrigerant tube to the water tube. A housing surrounds said coiled tubes and said sleeves, and sealed end caps are provided at each end of the exchanger.