Abstract: A heating/cooling system includes a closed circuit refrigeration system including an evaporator. Water circulating through a closed water circuit exchanges heat with refrigerant in the evaporator, cooling the water for a cooling application. The water can also be heated by a boiler, and the heated water is used to heat a space. A water pump flows the water through the water circuit. When a current sensing relay detects a power failure, a boiler control algorithm is initiated to “trick” a motor of the compressor into believing the heating/cooling system is operating in a heating mode. Therefore, a compressor failure alarm is not generated. The water pump is powered by a battery pack during the power failure. Water continues to flow through the water circuit, preventing the water from freezing.

Abstract: A heating/cooling system includes a closed circuit refrigeration system including an evaporator. Water circulating through a closed water circuit exchanges heat with refrigerant in the evaporator, cooling the water for a cooling application. The water can also be heated by a boiler, and the heated water is used to heat a space. A water pump flows the water through the water circuit. When a current sensing relay detects a power failure, a boiler control algorithm is initiated to “trick” a motor of the compressor into believing the heating/cooling system is operating in a heating mode. Therefore, a compressor failure alarm is not generated. The water pump is powered by a battery pack during the power failure. Water continues to flow through the water circuit, preventing the water from freezing.