| 摘要 |
A hot water supply device is configured so as to appropriately change the flow rate of hot water flowing through a circulation circuit, preventing the deposition of foreign matter such as scale and consistently performing heating operation. A hot water supply device is provided with a heat pump unit (1), a hot water storage tank (11), a circulation pump (12), a control device (30), and other devices. When performing heating operation, the control device (30) controls the rotational speed of the circulation pump (12), performing: steady operation in which the circulation flow rate of hot water flowing through the secondary flow passage (3A) of a water heating heat exchanger (3) is maintained at a steady flow rate (A); and pulsating operation in which the circulation flow rate is temporarily reduced and increased relative to the steady flow rate (A). Also, the control device (30) maintains the difference (&Dgr;A) between the maximum value (AH) and the minimum value (AL) of the circulation flow rate during the pulsating operation at a value greater than or equal to a reference value (S) at which the deposition of foreign matter on the inside of the secondary flow passage (3A) is capable of being restricted. As a result of this configuration, the hot water supply device is capable of consistently performing heating operation and restricting the deposition of scale utilizing the pulsation of the circulation flow rate. |
