Patent attributes
An embodiment of the instant disclosure comprises a reversible heat pump and water heating system for conditioning a space and heating water. The system comprises a refrigerant circuit that includes a compressor, a source heat exchanger, a space heat exchanger, and an expansion device. A 4-way reversing valve alternates between heating and cooling modes of operation. The system includes a heat exchanger for heating water in the water heating loop, and a 3-way valve that either actuates the refrigerant flow through the water heater heat exchanger or bypasses at least a portion of the refrigerant flow around the water heater heat exchanger. The heat pump system is operable in at least five modes—space heating only, space cooling only, water heating only, and either space heating or space cooling combined with water heating. Use of a modulating 3-way valve allows the amount of the refrigerant flow through the water heating heat exchanger to be adjusted to precisely match space conditioning and water heating demands and stable operation of the heat pump system. Either of the space and source heat exchangers may be bypassed and deactivated to reduce the heat pump system power consumption.