Abstract: An apparatus and method for cooling water in a swimming pool includes a heat exchanger coupled to a withdrawal conduit and a skimmer conduit of the pool filtering system. The heat exchanger is buried in the ground at a depth at which the ground temperature is substantially constant year-round thereby providing a passive heat sink for the heat exchanger. Water from the swimming pool is passed to a three-way valve for directing pool water either directly back to the swimming pool or through the heat exchanger for cooling pool water by heat transfer to the ground heat sink before being returned to the pool. Pool water from the skimmer conduit is selectively directed through the heat exchange while flow of pool water from the withdrawal conduit is prevented. A temperature sensor may control operation of the three-way valve and selective operation of the skimmer and withdrawal conduits.

Abstract: An apparatus and method for cooling water in a swimming pool includes a heat exchanger coupled to a return conduit of the pool filtering system. The heat exchanger is buried in the ground at a depth at which the ground temperature is substantially constant year-round thereby providing a passive heat sink for the heat exchanger. Water from the swimming pool is passed to a three-way valve for directing pool water either directly back to the swimming pool or through the heat exchanger for cooling pool water by heat transfer to the ground heat sink before being returned to the pool. A temperature sensor may be disposed within the pool water to control the operation of the valve at a predetermined pool temperature above which pool water is directed through the heat exchanger for cooling.