Heat pump system with auxiliary heat exchanger

A method of operating a heat pump system in a heating mode of operation, the heat pump system comprising:

• one or more indoor heat exchangers;
• one or more compressors;
• one or more refrigerant superheat controllers;
• one or more reversing valves;
• one or more outdoor heat exchangers;
• and
• an auxiliary system comprising:
• one or more auxiliary energy sources comprising a water heater;
• one or more first flow diverting valves;
• one or more second flow diverting valves;
• and
• one or more auxiliary heat exchangers located outdoors, each auxiliary heat exchanger paired with a set of the first and second flow diverting valves and with a corresponding one of the outdoor heat exchangers, each auxiliary heat exchanger located adjacent a corresponding outdoor heat exchanger,
• the water heater including a water loop for supplying heated water along a water flow path to at least one of the one or more auxiliary heat exchangers;
• the set of first and second flow diverting valves operable to selectively define a refrigerant flow path through either a corresponding auxiliary heat exchanger or a corresponding outdoor heat exchanger, such that when the refrigerant flow path is defined through the corresponding auxiliary heat exchanger the corresponding outdoor heat exchanger is isolated, and when the refrigerant flow path is defined through the corresponding outdoor heat exchanger the corresponding auxiliary heat exchanger is isolated;
• the method comprising:
• determining a heat pump operating parameter;
• once the heat pump operating parameter has reached a predetermined operating value and an outdoor temperature is 32 degrees Fahrenheit or less:
• inhibiting a flow of refrigerant to each outdoor heat exchanger that is configured for the heating mode of operation;
• and
• enabling said flow of refrigerant to pass through each corresponding paired auxiliary heat exchanger;
• and
• operating the one or more auxiliary energy sources when said flow of refrigerant through any one or more auxiliary heat exchangers is enabled, thereby exchanging thermal energy between the activated auxiliary energy source(s) and refrigerant flowing through one or more auxiliary heat exchangers, the auxiliary energy source(s) operated so as to substantially maintain a desired temperature for water supplied by the water heater, for one or more auxiliary heat exchangers, and/or for refrigerant flowing through one or more auxiliary heat exchangers.

A heat pump system comprising:

• one or more indoor heat exchangers;
• one or more compressors;
• one or more refrigerant superheat controllers;
• one or more reversing valves;
• one or more outdoor heat exchangers, each paired with an auxiliary heat exchanger that is located outdoors, each auxiliary heat exchanger located adjacent a corresponding one of said one or more outdoor heat exchangers;
• one or more auxiliary energy sources comprising a boiler;
• first and second flow diverting valves, or four flow valves, operable to selectively define a refrigerant flow path either through one of the one or more outdoor heat exchangers or through a corresponding auxiliary heat exchanger, such that when the refrigerant flow path is defined through the corresponding auxiliary heat exchanger the corresponding outdoor heat exchanger is isolated, and when the through flow path is defined through an outdoor heat exchanger the corresponding auxiliary heat exchanger is isolated;
• the heat pump system operable to:
• inhibit a flow of refrigerant to each outdoor heat exchanger that is configured for a heating mode of operation, and enable said flow of refrigerant to pass through each corresponding paired auxiliary heat exchanger once the heat pump operating parameter has reached a predetermined operating value;
• and
• activate the one or more auxiliary energy sources when said flow of refrigerant through any one or more auxiliary heat exchangers is enabled, thereby exchanging thermal energy between the activated auxiliary energy source(s) and refrigerant flowing through one or more auxiliary heat exchangers, so as to substantially maintain a desired temperature for water supplied by the boiler, for one or more auxiliary heat exchangers, and/or for refrigerant flowing through one or more auxiliary heat exchangers.