| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat pump type water heater that prevents shortage of boiling-up amount even if frequency of a compressor is reduced during a defrosting operation to reduce noise.SOLUTION: A heat pump type water heater includes: a hot water storage tank 8 for storing hot water; a compressor 1 for compressing a refrigerant; a water-refrigerant heat exchanger 2 in which the refrigerant from the compressor 1 flows on the primary side and water in a heating circulation circuit 11 flows on the secondary side; decompression and expansion means 3 for decompressing and expanding the refrigerant flowing out from the water-refrigerant heat exchanger 2; an air heat exchanger 4 through which the refrigerant from the decompression and expansion means 3 flows; and a control section 20 for performing control to conduct a boiling-up operation for boiling up all or almost all of hot water to be used on the following day in a late-night time zone. In a quiet time zone preset related to the late-night time zone, defrosting control means changes a defrosting start condition to a direction for facilitating start of defrosting and reduces the operating frequency of the compressor 1 during the defrosting operation compared to that of the compressor 1 during the defrosting operation in time zones excluding than the quiet time zone.SELECTED DRAWING: Figure 1 |
