HEATING SYSTEM

摘要

Provided is a heating system that can improve a coefficient of performance (COP) in a case where a heat medium is heated stepwise by a plurality of refrigeration cycles. The heating system is provided with the following: first and second refrigeration cycles provided with first and second water-refrigerant heat exchangers that perform heat exchange on water and a refrigerant ejected from a compressor; a water pipe that causes water to flow in series in a water side flow path of the first and second water-refrigerant heat exchangers of the plurality of refrigeration cycles; a warm water storage tank that stores water (warm water) heated by the first and second refrigeration cycles; and a pipe for additional heating, a circulation pump for additional heating, a three-way valve, and a controller that constitute an additional heating means that heats the warm water in the warm water storage tank by running only the second refrigeration cycle on the lowest downstream side provided with the second water-refrigerant heat exchanger positioned at the lowest downstream side of the water flow direction.