Heat pump system for production of domestic hot water

Claim 1

A heat pump system for heating a heat storage medium of the type in which a working fluid enters a compressor as a vapor at low pressure wherein the vaporized working fluid is compressed and thus heated, leaves the compressor and enters a heat exchanging condenser as a vapor at elevated pressure, there condenses as a result of heat transfer to the heat storage medium, the condensed working fluid enters an expander where the pressure and temperature decreases, the low pressure and temperature working fluid enters an evaporator where the working fluid is vaporized and returns to the compressor, the movement in combination therewith comprising: a compressor means capable of compressing the working fluid to multiple distinct pressure levels; multiple condensers operating at said multiple distinct pressure levels wherein said condensers and said heat storage medium are arranged with the higher pressure condenser in heat exchange relationship with a higher temperature region of said heat storage medium; and multiple expanders associated with said multiple condensers and with said evaporator, wherein said working fluid from said multiple condensers is expanded to a single low pressure and temperature before entering said evaporator, said working fluid vaporized in said evaporator.

Claim 7

A method for heating a heat storage medium utilizing a heat pump system using working fluid to transfer heat from the working fluid to the heat storage medium comprising in combination the steps of: compressing said working fluid to a multiplicity of distinct pressure levels; condensing said compressed working fluid compressed to a multiplicity of distinct pressure levels in a multiplicity of condensers in heat exchange relation with said heat storage medium wherein the condenser in fluid communication with the higher of said distinct pressure is arranged to be in heat exchange relationship with the higher temperature heat storage medium thereby efficiently transferring heat from said working fluid to said heat storage medium; expanding independently in a multiplicity of expanders said condensed working fluid from said condensers to a single uniform low pressure; and the vaporizing in a single evaporator said low pressure working fluid said vaporizing resulting from heat transer from a low temperature heat source said vaporized low pressure working fluid being in fluid communication with said compressing step.

Claim 8

A method for heating a heat storage medium utilizing a heat pump system using working fluid to transfer heat from the working fluid to the heat storage medium comprising in combination the steps of: compressing said working fluid to a multiplicity of distinct pressure levels; condensing said compressed working fluid compressed to a multiplicity of distinct pressure levels in a multiplicity of condensers in heat exchange relation with said heat storage medium wherein the condenser in fluid communication with the higher of said distinct pressure is arranged to be in heat exchange relationship with the higher temperature heat storage medium thereby efficiently transferring heat from said working fluid to said heat storage medium; expanding independently in a multiplicity of expanders said condensed working fluid from said condensers to a single uniform low pressure; and the vaporizing in a single evaporator said low pressure working fluid said vaporizing resulting from heat transer from a low temperature heat source said vaporized low pressure working fluid being in fluid communication with said compressing step.