APPARATUS AND METHOD FOR HYBRID WATER HEATING AND AIR COOLING AND CONTROL THEREOF

1 . A system for conditioning air and for heating water, comprising:

a refrigerant path;

a first condenser in the refrigerant path and disposed in an air flow path so that the first condenser transfers heat to air in the air flow path from refrigerant moving through the first condenser in the refrigerant path;

a second condenser in the refrigerant path and that defines a water flow path so that the second condenser transfers heat to water in the water flow path from refrigerant moving through the second condenser in the refrigerant path;

a control system in operative communication with the refrigerant path and configured to selectively direct the refrigerant through the first condenser or through the second condenser; and

a temperature sensor disposed in the water flow path,

wherein the control system is in operative communication with the temperature sensor to receive a signal from the temperature sensor indicating temperature of water in the water flow path,

wherein the control system is configured to move the refrigerant path between a first state, in which the control system directs refrigerant through the first condenser and not through the second condenser, and a second state, in which the control system directs refrigerant through the second condenser, and

wherein the control system is configured to

move the refrigerant path from the first state to the second state in response to the temperature of the water indicated by the temperature sensor being below a threshold temperature, and

select the threshold temperature based upon a predetermined operating parameter of the refrigerant circuit.

2 . The system as in claim 1 ,

comprising a pressure sensor disposed in the refrigerant path,

wherein the control system is in operative communication with the pressure sensor to receive a signal from the pressure sensor indicating pressure of refrigerant in the refrigerant path,

wherein the control system is configured to move the refrigerant path from the second state to the first state if the pressure of refrigerant indicated by the pressure sensor is above a predetermined pressure, and

wherein the operating parameter is temperature of water in the water flow path when the pressure of refrigerant indicated by the pressure sensor is above the predetermined pressure.

3 . The system as in claim 2 , wherein the control system is configured to select the threshold temperature in response to the temperature of water in the water flow path according to a predetermined correlation between the temperature of water in the water flow path and pressure in the refrigerant path.

4 . The system as in claim 2 , comprising an evaporator in the refrigerant path and disposed in a second air flow path so that air in the second air flow path transfers heat to refrigerant that moves through the evaporator, and wherein the water flow path is directed from an area in a building from which the second air flow path is also directed.

5 . The system as in claim 1 ,

comprising an evaporator in the refrigerant path and disposed in a second air flow path so that air in the second air flow path transfers heat to refrigerant that moves through the evaporator, and

wherein the operating parameter is temperature of air in the second air flow path.

6 . The system as in claim 5 ,

comprising an air temperature sensor disposed in the second air flow path, and

wherein the control system is in operative communication with the air temperature sensor to receive a signal from the air temperature sensor indicating temperature of the second air flow path.

7 . The system as in claim 6 ,

comprising a pressure sensor disposed in the refrigerant path,

wherein the control system is in operative communication with the pressure sensor to receive a signal from the pressure sensor indicating pressure of refrigerant in the refrigerant path,

wherein the control system is configured to move the refrigerant path from the second state to the first state if the pressure of refrigerant indicated by the pressure sensor is above a predetermined pressure, and

wherein the operating parameter is temperature of air in the second air flow path, as indicated by the signal from the air temperature sensor, when the pressure of refrigerant indicated by the pressure sensor is above the predetermined pressure.

8 . The system as in claim 7 , wherein the control system is configured to select the threshold temperature in response to the temperature of the air in the second air flow path according to a predetermined correlation between the temperature of the air in the second air flow path and pressure in the refrigerant path.

9 . A system for conditioning air and for heating water, comprising:

a refrigerant path;

a first condenser in the refrigerant path and disposed in an air flow path so that the first condenser transfers heat to air in the air flow path from refrigerant moving through the first condenser in the refrigerant path;

a second condenser in the refrigerant path and that defines a water flow path so that the second condenser transfers heat to water in the water flow path from refrigerant moving through the second condenser in the refrigerant path;

a compressor in the refrigerant path and configured to move refrigerant in the refrigerant path;

a control system in operative communication with the refrigerant path and configured to selectively direct the refrigerant from the compressor to the first condenser or the second condenser;

a pressure sensor disposed in the refrigerant path; and

a temperature sensor disposed in the water flow path,

wherein the control system is in operative communication with

the pressure sensor to receive a signal from the pressure sensor indicating pressure of refrigerant in the refrigerant path, and

the temperature sensor to receive a signal from the temperature sensor indicating temperature of water in the water flow path,

wherein the control system is configured to move the refrigerant path between a first state, in which the control system directs refrigerant from the compressor to the first condenser and not to the second condenser, and a second state, in which the control system directs refrigerant from the compressor to the second condenser, and

wherein the control system is configured to

move the refrigerant path from the first state to the second state if the temperature of the water indicated by the temperature sensor is below a threshold temperature, and

select the threshold temperature based upon the pressure of refrigerant indicated by the pressure sensor.

10 . The system as in claim 9 ,

wherein the control system is configured to move the refrigerant path from the second state to the first state if the pressure of refrigerant indicated by the pressure sensor is above a predetermined pressure, and

wherein the control system is configured to select the threshold temperature based upon temperature of water in the water flow path, as indicated by the temperature sensor, when the pressure of refrigerant indicated by the pressure sensor is above the predetermined pressure.

11 . The system as in claim 10 , wherein the control system is configured to select the threshold temperature in response to the temperature of water in the water flow path according to a predetermined correlation between the temperature of water in the water flow path and pressure in the refrigerant path.

12 . The system as in claim 10 , comprising an evaporator in the refrigerant path and disposed in a second air flow path so that air in the second air flow path transfers heat to refrigerant that moves through the evaporator, and wherein the water flow path is directed from an area in a building from which the second air flow path is also directed.

13 . The system as in claim 9 ,

comprising an evaporator in the refrigerant path and disposed in a second air flow path so that air in the second air flow path transfers heat to refrigerant that moves through the evaporator,

comprising a temperature sensor disposed in the air in the second air flow path, and

wherein the control system is in operative communication with the temperature sensor to receive a signal from the temperature sensor indicating temperature of the air in the second air flow path.

14 . The system as in claim 13 ,

wherein the control system is configured to move the refrigerant path from the second state to the first state if the pressure of refrigerant indicated by the pressure sensor is above a predetermined pressure, and

wherein the control system is configured to select the threshold temperature based upon temperature of air in the second air flow path, as indicated by the signal from the air temperature sensor, when the pressure of refrigerant indicated by the pressure sensor is above the predetermined pressure.

15 . The system as in claim 14 , wherein the control system is configured to select the threshold temperature in response to the temperature of the air in the second air flow path according to a predetermined correlation between the temperature of the air in the second air flow path and pressure in the refrigerant path.

16 . A system for conditioning air and for heating water, comprising:

a refrigerant path;

a first condenser in the refrigerant path and disposed in a first air flow path so that the first condenser transfers heat to air in the air flow path from refrigerant moving through the first condenser in the refrigerant path;

a second condenser in the refrigerant path and that defines a water flow path so that the second condenser transfers heat to water in the water flow path from refrigerant moving through the second condenser in the refrigerant path;

an evaporator in the refrigerant path and disposed in a second air flow path so that air in the second air flow path transfers heat to refrigerant that moves through the evaporator;

a compressor in the refrigerant path and configured to move refrigerant in the refrigerant path;

a control system comprising a controllable valve in the refrigerant path in communication with the compressor, the first condenser, and the second condenser so that the controllable valve selectively directs the refrigerant from the compressor to the first condenser or the second condenser;

a pressure sensor disposed in the refrigerant path; and

a temperature sensor disposed in the water flow path,

wherein the control system is in operative communication with

the compressor to activate and deactivate the compressor,

the pressure sensor to receive a signal from the pressure sensor indicating pressure of refrigerant in the refrigerant path,

the temperature sensor to receive a signal from the temperature sensor indicating temperature of water in the water flow path,

wherein the control system is configured to move the controllable valve between a first state, in which the controllable valve directs the refrigerant from the compressor to the first condenser and not to the second condenser, and a second state, in which the controllable valve directs refrigerant from the compressor to the second condenser, and

wherein the control system is configured to

move the controllable valve from the first state to the second state if the temperature of the water indicated by the temperature sensor is below a threshold temperature, and

select the threshold temperature based upon the pressure of refrigerant indicated by the pressure sensor.

17 . The system as in claim 16 , wherein the water flow path is directed from an area in a building from which the second air flow path is also directed, and wherein the control system is configured to

after moving the controllable valve from the first state to the second state, monitor the signal from the pressure sensor, and

if the pressure of refrigerant indicated by the pressure sensor exceeds a predetermined threshold,

move the controllable valve from the second state to the first state, and

reset the threshold temperature directly based on temperature of the water indicated by the temperature sensor.

18 . A system for conditioning air and for heating water, comprising:

a refrigerant path;

a first condenser in the refrigerant path and disposed in a first air flow path so that the first condenser transfers heat to air in the first air flow path from refrigerant moving through the first condenser in the refrigerant path;

a second condenser in the refrigerant path and that defines a water flow path so that the second condenser transfers heat to water in the water flow path from refrigerant moving through the second condenser in the refrigerant path;

an evaporator in the refrigerant path and disposed in a second air flow path so that air in the second air flow path transfers heat to refrigerant moving through the evaporator;

a control system in operative communication with the refrigerant path and the temperature sensor and configured to selectively direct refrigerant flow through the first condenser or the second condenser; and

a temperature sensor disposed in the water flow path,

wherein the control system is configured to

compare a water temperature measured by the temperature sensor to a threshold temperature,

move the refrigerant path between a first state, in which the control system directs refrigerant through the first condenser and not through the second condenser, and a second state, in which the control system directs refrigerant through the second condenser in response to comparison of the water temperature to the threshold temperature, and

select the threshold temperature in response to an operating parameter of the refrigerant circuit that varies with temperature of air in the second air flow path.

19 . The system as in claim 18 , wherein the operating parameter is temperature of air in the second air flow path.

20 . The system as in claim 18 , wherein the operating parameter is temperature of water in the water flow path.