US Patent 9752803 Heat pump system with a flow directing system

A heat pump system is provided that includes a flow directing system that allows an outdoor heat exchanger to be switchable between a single-pass arrangement and a two-pass arrangement. The heat pump system includes an outdoor heat exchanger, an indoor heat exchanger, and a flow directing system of check valves and piping segments that enable switching of the outdoor heat exchanger between the single-pass and the two-pass arrangement. The outdoor heat exchanger is operable as a two-pass condenser in the cooling mode and as a single-pass evaporator in the heating mode.