Combination refrigerant circuit and hot water preheater

Claim 1

A combination referigeration circuit including a compressor and a hot water heating system which comprises: a water inlet for receiving water to be heated; a water outlet for discharging water to a storage tank and a hot water tap through a single conduit; a pump connected to receive water from the water inlet and to circulate water through the water heating system to the water outlet, said pump being energized in conjunction with the compressor; heat exchange means connected to receive hot gaseous refrigerant from the refrigeration circuit and to effect a transfer of heat energy from said refrigerant to the water flowing through the hot water heating system; a first water conduit means connecting the heat exchange means to the pump; valve means located downstream of said heat exchange means to control the flow of water from the heat exchange means to the water outlet; a second water conduit means connecting the heat exchange means to the valve means; a third water conduit means connecting the valve means to the water outlet; a bypass means including a flow restriction for limiting flow therethrough connecting the first conduit means to the third conduit means; an entering water temperature sensor located upstream of said pump; a leaving water temperature sensor located within said second water conduit means; a safety temperature sensor located downstream of said bypass means within said third conduit means for sensing the temperature of the water flowing to the water outlet through the third conduit means including water flowing through the bypass means; and circuit means connecting contacts of the safety temperature sensor, said entering water temperature sensor, and said leaving water temperature sensor in series with the valve means, and said contacts of said safety temperature sensor in series with said pump and compressor, which are in parallel, whereby said valve means is open only when said contacts of all three of said safety temperature sensor, said entering water temperature sensor, and said leaving water temperature sensor are closed by sensing the appropriate temperature conditions, and said compressor and said pump are running when only said contacts of said safety temperature sensor are closed.