Direct expansion ground source heat pump

摘要

A direct expansion ground source heat pump operable in heating mode and cooling mode. The heat pump comprises an outdoor coil, an indoor coil and a compressor. The outdoor coil and the indoor coil are coupled to the compressor through a reversing valve and the compressor provides a refrigerant flow through the coils. The indoor coil and outdoor coil are coupled together through a controllable valve. The outdoor coil comprises two coil circuits. In heating mode both ground coil circuits are active, while in cooling mode, the heat pump utilizes one of the coil circuits and alternates between coil circuits each compressor cycle.