| 摘要 |
PROBLEM TO BE SOLVED: To prevent execution of a defrosting operation of a heat pump device immediately after shifting from a second time zone to a first time zone as much as possible, in an operation in an operation mode to make a supply temperature of a heat medium to a heat radiation terminal machine in the second time zone, lower than that in the first time zone.SOLUTION: Defrost control means 72 of a heating system 1 executes a defrosting operation of a heat pump device 3 even when a frost formation degree of the heat pump device 3 is smaller than a prescribed value, in a case when a present time reaches a time of a predetermined prescribed time zone just before termination of the second time zone, in the operation in a heat medium supply temperature switching mode to make a supply temperature of a heat medium to a heat radiation terminal machine 5L in the second time zone lower than that of the first time zone.SELECTED DRAWING: Figure 3 |
