Abstract: An economical heat pump system which uses a multifluid heat exchanger and the basic components of conventional heat pump systems including, as appropriate, a desuperheat exchanger. The invention may be operated in two conventional refrigerant flow configurations including heat pump space heating and cooling and simultaneous hot water heating via the desuperheater. The use of a multifluid heat exchanger allows the two refrigerant flow configurations to have nine operational modes. In one flow configuration the refrigerant is from the compressor, through the desuperheater, through a reversing valve, through the outdoor heat exchanger, through an expansion device, through the indoor heat exchanger and back to the compressor via the reversing valve. In the second configuration, the refrigerant flow is from the compressor, through the desuperheater, through the reversing valve, through the indoor heat exchanger, through an expansion device, through the outdoor heat exchanger and back to the compressor.

Abstract: Systems for transferring energy between a conditioned zone, a heat source or sink liquid, and an ambient zone including combination liquid-source, air-source heat pumps with multi-fluid reversing means and an easily manufactured multi-fluid heat exchanger. Specifically three types of heat pumps: a split system of unitary type with conventional refrigerant reversing means, multi-fluid heat exchanger(s), and heat source or sink fluid reversing means; a self-contained or packaged type with conventional refrigerant reversing means, a multi-fluid heat exchanger, a conventional liquid-to-refrigerant heat exchanger, heat source or sink liquid reversing means, and innovative component arrangement which allows ambient air to be utilized as a heat source or sink fluid; a self-contained or packaged type with innovative component arrangement which allows air reversing means, multi-fluid heat exchangers, and heat source or sink liquid reversing means.