DEVICE AND METHOD FOR AIR-COOLING AND HOT-WATER SUPPLY

摘要

A combined air-conditioning and hot water supply system for simultaneously executing a cooling operation and a hot water supply operation is provided, in which the operation of a compressor is controlled to complete hot water supply with high efficiency and in a short time to thereby prevent running out of hot water. In a case where a combined air-conditioning and hot water supply system 100 simultaneously executes the cooling operation of a use unit 303 and the hot water supply operation of a hot water supply unit 304, the combined air-conditioning and hot water supply system 100 operates in a cooling priority mode when the temperature differential ”T wm between a set hot water supply temperature T wset and the inlet water temperature T wi of a plate water-heat exchanger 16 is smaller than a priority operation determination threshold M that is set in advance, and operates in a hot water supply priority mode when the temperature differential ”T wm becomes equal to or higher than the priority operation determination threshold M. In the cooling priority mode, the operating frequency of a compressor 1 is controlled in accordance with the temperature differential between the suction air temperature of the use unit 303 and the indoor set temperature of the use unit 303. In the hot water supply priority mode, the operating frequency of the compressor 1 is controlled in accordance with the temperature differential between the set hot water supply temperature T wset and the water temperature in a hot water supply tank 305.