Abstract: A heat pump unit capable of producing hot potable water irregardless of the heating or cooling operation of the heat pump. The heat pump for heating or cooling a conditioned space with potable water heating capability. The heat pump unit having a compressor with a service port, an entrance port and a discharge. A three-way valve is provided connected to the discharge and to the service port of the compressor, and reversing valve is connected to the three-way valve and to the compressor entrance port. A refrigerant-air heat exchanger is connected to the reversing valve outlet and an external source-refrigerant heat exchanger is connected to the reversing valve with a refrigerant-potable water heat exchanger connected to the three-way valve.