| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot water supply device capable of shortening operation time even if temperature of water entering a water heat exchanger rises and suppressing the reduction of COP. SOLUTION: This hot water supply device is provided with a refrigerant circuit R having a compressor 25, the water heat exchanger 26, a pressure reduction mechanism 24, and an evaporator 30. Ultra-critical refrigerant used in an ultra-critical state is used as refrigerant in the refrigerant circuit R. The water heat exchanger 26 functions as a condenser to heat hot water passing through the water heat exchanger 26. A refrigerant circulation amount in the refrigerant circuit R is increased more when temperature of water entering the water heat exchanger 26 is high than when the temperature thereof is low. |
