Refrigerant System With Water Heating

Abstract

A heat pump system ( 10 ) includes a compressor ( 20 ), a reversing valve ( 30 ), an outdoor heat exchanger ( 40 ) and an indoor heat exchanger ( 50 ) coupled via refrigerant lines ( 35, 45 ) in a conventional refrigeration circuit, and a refrigerant-to-water heat exchanger ( 60 ). In the air cooling with water heating mode, the air heating with water heating mode and the water heating only mode, water from a water reservoir ( 64 ), such as a storage tank or swimming pool, is passed through heat exchanger ( 60 ) in heat exchange relationship with refrigerant passing through an additional refrigerant line ( 27 ) that establishes a fluid flow path through the heat exchanger ( 60 ) into the refrigerant circuit intermediate the outdoor heat exchanger ( 40 ) and indoor heat exchanger ( 50 ). A refrigerant reservoir ( 70 ) may be provided for use in refrigerant charge control.

1 . A refrigerant system operable in at least an air cooling mode and having liquid heating capability comprising:
 a refrigerant compressor having a suction port and a discharge port;   a selectively positionable reversing valve having a first port, a second port, a third port and a fourth port, said reversing valve being positionable in a first position for coupling the first port and the second port in fluid flow communication and the third port and the fourth port in fluid flow communication, said reversing valve being positionable in a second position for coupling the first port and the fourth port in fluid flow communication and the second port and the third port in fluid flow communication;   a refrigerant circuit providing a closed loop refrigerant circulation flow path, said refrigerant circuit having a first refrigerant line establishing a flow path between the discharge port of said compressor and the first port of said reversing valve and a second refrigerant line establishing a flow path between the second port of said reversing valve and the suction port of said compressor;   an outdoor heat exchanger operatively associated with the second refrigerant line and adapted for passing refrigerant passing through the second refrigerant line in heat exchange relationship with ambient air;   an indoor heat exchanger operatively associated with the second refrigerant line and adapted for passing refrigerant passing through the second refrigerant line in heat exchange relationship with the air from the comfort zone, said indoor heat exchanger disposed downstream of said outdoor exchanger with respect to refrigerant flow in the air cooling mode;   a third refrigerant line establishing a flow path between the fourth port of said reversing valve and the second refrigerant line at a location intermediate said outdoor heat exchanger and said indoor heat exchanger;   a refrigerant to liquid heat exchanger operatively associated with the third refrigerant line and adapted for passing refrigerant passing through the third refrigerant line in heat exchange relationship with a liquid;   a first flow control valve disposed in the second refrigerant line intermediate said outdoor heat exchanger and the location of the intersection of the third refrigerant line with the second refrigerant line, said first control valve having an open position and a closed position;   a second flow control valve disposed in the second refrigerant line intermediate said indoor heat exchanger and the location the intersection of the third refrigerant line with said second refrigerant line, said second control valve having an open position and a closed position;   a controller operatively associated with said first and second flow control valves, said controller operative to selectively control the respective positioning of said first and second flow control valves between their respective open and closed positions so as to selectively control refrigerant flow through the second refrigerant line; and   a refrigerant reservoir having an inlet coupled in fluid flow communication to said second refrigerant line at a location intermediate said outdoor heat exchanger and said indoor heat exchanger and an outlet coupled in fluid flow communication to the second refrigerant line at a location intermediate the indoor heat exchanger and the suction port of said compressor.   
   
   
       2 . A system as recited in  claim 1  further comprising a flow check valve disposed in the third refrigerant line so as to permit refrigerant flow therethrough in a direction from said reversing valve into the second refrigerant line and to block flow from the second refrigerant line to said reversing valve. 
   
   
       3 . A system as recited in  claim 2  further comprising a fourth refrigerant line establishing a flow path between a refrigerant flow path between the third port of said reversing valve and the suction port of said compressor. 
   
   
       4 . A system as recited in  claim 1  further comprising:
 a first flow control valve operatively associated with said refrigerant reservoir for controlling the flow refrigerant from the second refrigerant line to the inlet of said refrigerant reservoir, said first control valve having an open position and a closed position;   a second flow control valve operatively associated with said refrigerant reservoir for controlling the flow refrigerant between the outlet of said refrigerant reservoir and the second refrigerant line at a location intermediate the indoor heat exchanger and the suction port of said compressor, said second control valve having an open position and a closed position; and   a controller operatively associated with said first and second flow control valves, said controller operative to selectively control the respective positioning of said first and second flow control valves between their respective open and closed positions so as to selectively control the refrigerant charge within the refrigerant circuit.   
   
   
       5 . A system as recited in  claim 4  wherein said first and second flow control valves operatively associated with said refrigerant reservoir comprise valves having at least one partially open position between their respective open and closed positions; and
 said controller is further operative to selectively modulate the respective positioning of said first and second flow control valves operatively associated with said refrigerant reservoir between their open, at one partially open and closed positions.   
   
   
       6 . A system as recited in  claim 5  wherein said first and second flow control valves operatively associated with said refrigerant reservoir comprise pulse width modulated solenoid valves. 
   
   
       7 . A system as recited in  claim 4  further comprising a liquid level sensor operatively associated with said refrigerant reservoir, said liquid level sensor operative to sense the level of liquid refrigerant in said refrigerant reservoir and provide a signal indicative of the liquid level within said refrigerant reservoir to said controller. 
   
   
       8 . A system as recited in  claim 7  wherein said controller is operative to selectively control the respective positioning of said first and second flow control valves operatively associated with said refrigerant reservoir between their respective open and closed positions so as to selectively control the refrigerant charge within the refrigerant circuit in response to the liquid level signal received from said liquid level sensor. 
   
   
       9 . A refrigerant circuit heat pump system operable in at least an air cooling mode and an air heating air mode and having liquid heating capability comprising:
 a refrigerant compressor having a suction port and a discharge port;   a first selectively positionable reversing valve having a first port, a second port, a third port and a fourth port, said reversing valve being positionable in a first position for coupling the first port and the second port in fluid flow communication and the third port and the fourth port in fluid flow communication, said reversing valve being positionable in a second position for coupling the first port and the fourth port in fluid flow communication and the second port and the third port in fluid flow communication;   a refrigerant circuit providing a closed loop refrigerant circulation flow path, said refrigerant circuit having a first refrigerant line establishing a flow path between the discharge port of said compressor and the first port of said first reversing valve and a second refrigerant line establishing a flow path between the second port of said first reversing valve and the suction port of said compressor;   an outdoor heat exchanger operatively associated with the second refrigerant line and adapted for passing refrigerant passing through the second refrigerant line in heat exchange relationship with ambient air;   an indoor heat exchanger operatively associated with the second refrigerant line and adapted for passing refrigerant passing through the second refrigerant line in heat exchange relationship with the air from the comfort zone, said indoor heat exchanger disposed downstream of said outdoor exchanger with respect to refrigerant flow in the air cooling mode;   a second selectively positionable valve having a first port, a second port, a third port and a fourth port, said second selectively positionable valve being positionable in a first position for coupling the first port and the second port in fluid flow communication and the third port and the fourth port in fluid flow communication, said second selectively positionable valve being positionable in a second position for coupling the first port and the third port in fluid flow communication and the second port and the fourth port in fluid flow communication;   a third refrigerant line establishing a flow path between the fourth port of said first reversing valve and the first port of said second reversing valve;   a fourth refrigerant line establishing a flow path between the third port of said second reversing valve and the second refrigerant line at a location intermediate said outdoor heat exchanger and said indoor heat exchanger;   a fifth refrigerant line establishing a flow path between the second port of said reversing valve and the second refrigerant line at a location intermediate said indoor heat exchanger and the suction inlet to said compressor;   a refrigerant to liquid heat exchanger operatively associated with the fourth refrigerant line and adapted for passing refrigerant passing through the fourth refrigerant line in heat exchange relationship with a liquid;   a first flow control valve disposed in the second refrigerant line intermediate said outdoor heat exchanger and the location the intersection of the third refrigerant line with the second refrigerant line, said first flow control valve having an open position and a closed position;   a second flow control valve disposed in the second refrigerant line intermediate said indoor heat exchanger and the location the intersection of the third refrigerant line with said second refrigerant line, said second flow control valve having an open position and a closed position;   a third flow control valve disposed in the second refrigerant line intermediate the location of the intersection of the fifth refrigerant line with the second refrigerant line and the suction inlet to said compressor, said third flow control valve having an open position and a closed position; and   a controller operatively associated with said first, second and third flow control valves, said controller operative to selectively control the respective positioning of said first, second and third flow control valves between their respective open and closed positions so as to selectively control refrigerant flow through the second refrigerant line.   
   
   
       10 . A heat pump system as recited in  claim 9  further comprising a flow check valve disposed in the fourth refrigerant line so as to permit refrigerant flow therethrough in a direction from said second reversing valve into the second refrigerant line and to block flow from the second refrigerant line to said second reversing valve. 
   
   
       11 . A heat pump system as recited in  claim 9  further comprising:
 a sixth refrigerant line establishing a refrigerant flow path between the third port of said first reversing valve and the suction port of said compressor; and   a seventh refrigerant line establishing a refrigerant flow path between the fourth port of said second reversing valve and the suction port of said compressor.   
   
   
       12 . A heat pump system as recited in  claim 9  further comprising a refrigerant reservoir having an inlet coupled in fluid flow communication to the second refrigerant line at a location intermediate said outdoor heat exchanger and said indoor heat exchanger and an outlet coupled in fluid flow communication to the second refrigerant line at a location intermediate the indoor heat exchanger and the suction port of said compressor. 
   
   
       13 . A heat pump system as recited in  claim 12  further comprising:
 a first flow control valve operatively associated with said refrigerant reservoir for controlling the flow refrigerant from the second refrigerant line to the inlet of said refrigerant reservoir, said first control valve having an open position and a closed position;   a second flow control valve operatively associated with said refrigerant reservoir for controlling the flow refrigerant between the outlet of said refrigerant reservoir and the second refrigerant line at a location intermediate the third flow control valve associated with the second refrigerant line and the suction port of said compressor, said second flow control valve having an open position and a closed position; and   a controller operatively associated with said first and second flow control valves operatively associated with said refrigerant reservoir, said controller operative to selectively control the respective positioning of said first and second flow control valves operatively associated with said refrigerant reservoir between their respective open and closed positions so as to selectively control the refrigerant charge within the refrigerant circuit.   
   
   
       14 . A heat pump system as recited in  claim 12  further comprising a liquid level sensor operatively associated with said refrigerant reservoir, said liquid level sensor operative to sense the level of liquid refrigerant in said refrigerant reservoir and provide a signal indicative of the liquid level within said refrigerant reservoir to said controller. 
   
   
       15 . A heat pump system as recited in  claim 14  wherein said controller is operative to selectively control the respective positioning of said first and second flow control valves operatively associated with said refrigerant reservoir between their respective open and closed positions so as to selectively control the refrigerant charge within the refrigerant circuit in response to the liquid level signal received from said liquid level sensor. 
   
   
       16 . A heat pump system as recited in  claim 9  wherein said controller is operative to cycle between the indoor air heating mode and the water heating mode whereby the system may effectively heat water while also heating air. 
   
   
       17 . A heat pump system as recited in  claim 9  further comprising:
 a first expansion valve disposed in the second refrigerant line intermediate said outdoor heat exchanger and the first flow control valve in the first refrigerant line; and   a second expansion valve disposed in the second refrigerant line intermediate said indoor heat exchanger and the second flow control valve in the second refrigerant line;   said first expansion valve being operative associated with said outdoor heat exchanger and said second expansion valve being operatively associated with said indoor heat exchanger.   
   
   
       18 . A heat pump system as recited in  claim 17  further comprising:
 a first expansion valve bypass line operatively associated with the second refrigerant line for bypassing refrigerant passing through the second refrigerant line in a direction from said outdoor heat exchanger to said indoor heat exchanger around said first expansion valve and through said second expansion valve.   
   
   
       19 . A heat pump system as recited in  claim 17  further comprising:
 a second expansion valve bypass line operatively associated with the second refrigerant line for bypassing refrigerant passing through the second refrigerant line in a direction from said indoor heat exchanger to said outdoor heat exchanger around said second expansion valve and through said first expansion valve.