In a WSHP, the Evaporator Coil is a tube filled with water called the Water Source Coil and sealed inside of another larger tube filled with Freon Gas. This is known as a TubeInATube Heat Exchanger. As the very cold Freon Gas flows through the outside tube of the Evaporator Coil the water flowing through the inside tube of the Evaporator Coil warms the Freon Gas. Purple The heat pump cycle begins as cold liquid refrigerant passes through a heat exchanger and absorbs heat from the water solution circulating through the ground loop.

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