A combination water heating, air conditioning refrigerant system is described. The combined system includes a plurality of independently adjustable electronic expansion valves. The expansion valves can independently modulate the delivery of high-temperature, high-pressure refrigerant to either a water heat exchanger or an outside condenser. A controller can receive input signals, including temperature signals from one or more temperature sensors that indicate the temperature at various locations of the system. The temperature signals include one or more of water temperature signals, ambient air temperature signals, or refrigerant super heat temperatures signals. In response to the input signals, the controller can output control signals to one or more of the plurality of electronic expansion valves.

When a heating operation mode using a heating unit is specified and when a hot water supply request using the hot water in a hot water storage tank does not occur, an air conditioning apparatus transmits a first selection signal for selecting the heating unit to a three-way valve. When the heating operation mode is specified and when the hot water supply request occurs, the air conditioning apparatus transmits, to the three-way valve, a second selection signal for changing a destination of circulation of secondary refrigerant from the heating unit to a coil heat exchanger, and transmits an operation start signal to a refrigerant indoor unit.

A combination water heating, air conditioning refrigerant system is described. The combined system includes a plurality of independently adjustable electronic expansion valves. The expansion valves can independently modulate the delivery of high-temperature, high-pressure refrigerant to either a water heat exchanger or an outside condenser. A controller can receive input signals, including temperature signals from one or more temperature sensors that indicate the temperature at various locations of the system. The temperature signals include one or more of water temperature signals, ambient air temperature signals, or refrigerant super heat temperatures signals. In response to the input signals, the controller can output control signals to one or more of the plurality of electronic expansion valves.

A supply-water warming system includes a steam compression heat pump circuit, a heat recovery heat exchanger, a heat source fluid line in which heat source fluid flows in the heat recovery heat exchanger and the evaporator in this order, a water supply line in which supply water flows in the heat recovery heat exchanger and the condenser in this order, a refrigerant flow rate adjustment section controlled based on the superheat degree of gas refrigerant flowing into the compressor and configured to adjust a refrigerant flow rate, a supply water flow rate adjustment section controlled based on the tapping temperature of the supply water flowing out of the condenser and configured to adjust a supply water flow rate, and a control section configured to control the refrigerant flow rate adjustment section and the supply water flow rate adjustment section.

A heat pump apparatus includes: a refrigerant circuit configured to circulate refrigerant having flammability; a heat medium circuit configured to allow a heat medium to flow therethrough; a heat-medium heat exchanger configured to exchange heat between the refrigerant and the heat medium; an outdoor unit configured to accommodate the refrigerant circuit and the heat-medium heat exchanger; and an indoor unit configured to accommodate a part of the heat medium circuit, the outdoor unit including a refrigerant release valve, the refrigerant release valve being at least one of a pressure relief valve and an air purge valve which are provided in the heat medium circuit, the refrigerant release valve being provided outside a casing of the outdoor unit.

A heat pump apparatus includes a use-side heat exchanger that causes heat exchange to be performed between a heat medium flowing from a heat-storage heat exchanger and a heat usage medium, and a flow-passage switching device that switches a flow passage for the heat medium to a first flow passage that circulates through a heat-reception-side heat exchanger and the heat-storage heat exchanger without extends through the use-side heat exchanger or a second flow passage that circulates through the heat-reception-side heat exchanger and the heat-storage heat exchanger via the use-side heat exchanger. Even when the temperature of the heat storage medium rises, heat received from a heat source can be stored in the heat storage medium by a heat pump, while a decrease of the efficiency of the heat pump can be reduced.

A method for controlling an operating discharge pressure in a multi-purpose HVAC system including an outdoor unit, and an indoor unit, the HVAC system including a plurality of flow control valves configured to isolate the indoor unit from the multi-purpose HVAC system, a compressor and a controller, operably coupled to a water heater module, the water heater module including at least one valve, the controller executing a method including operating the multi-purpose HVAC system in a water heating mode, monitoring the operating discharge pressure from the compressor; and generating a signal commanding at least one of the plurality of control valves to isolate the indoor unit from the outdoor unit and water heating module and direct high pressure refrigerant to the indoor unit when the operating discharge pressure is greater than or equal to a predetermined pressure value.

An outdoor unit includes an air heat exchanger; a compressor; a water heat exchanger; an expansion valve; a fan that moves air outside the outdoor unit into the air heat exchanger; a motor that rotates the fan; a power device used for driving the compressor; a heat sink located in a space that is an extension portion beyond the air heat exchanger, of a channel of air moved by rotation of the fan during heating of the water from outside the outdoor unit into the air heat exchanger, where the heat sink dissipates heat generated by the power device during driving of the compressor; and a control unit that provides control, upon completion of a water heating operation, to drive the compressor, to open the expansion valve, and to rotate the fan in the same direction as the rotation direction of the fan during heating of the water.

Heat pump system (100) comprising a heat medium circuit (210,220,230,240,250,310,320,410,420,430,440,450,460) in turn comprising at least three heat exchanging means (314,315,315,422,433,452) between the heat medium and a respective heat source or sink selected from outdoor air, a water body, the ground, indoor air, pool water or tap water, a valve means (311,312,313,421,431,451) arranged to selectively direct the heat medium to at least two of said heat exchanging means, and a control means (500). The invention is characterized in that the heat pump system comprises temperature sensors (314a,314b;315a,315b;316a,316b;423,424,425;432,434,435) both upstream and downstream of at least one of said heat exchanging means, in that the system determines, based upon temperature measurement values comprising at least one value read from said sensors, to what heat exchanging means the heat medium is to be directed, and in that when heat medium is not directed to a certain heat exchanging means a measured temperature value is read upstream and downstream of the certain heat exchanging means, and in that an alert is set off in case the values differ by more than a predetermined value. The invention also relates to a method.

A heat pump apparatus includes a use-side heat exchanger that cause heat exchange to be performed between a heat medium flowing from a heat-storage heat exchanger and a heat usage medium, and a flow-passage switching device that switches a flow passage for the heat medium to a first flow passage that circulates through a heat-reception-side heat exchanger and the heat-storage heat exchanger without extends through the use-side heat exchanger or a second flow passage that circulates through the heat-reception-side heat exchanger and the heat-storage heat exchanger via the use-side heat exchanger. Even when the temperature of the heat storage medium rises, heat received from a heat source can be stored in the heat storage medium by a heat pump, while a decrease of the efficiency of the heat pump can be reduced.