The hot water supply apparatus includes a heat pump unit operating using electrical energy, a hot water storage tank storing hot water heated by the heat pump unit, and an auxiliary heat source device burning fuel and heating hot water when a stored hot water heat amount is insufficient for a heat amount used for hot water supply. A control device calculates a predicted heat amount for each unit time period based on a past usage record of hot water supply; estimates an error distribution of an actual heat amount relative to the predicted heat amount; calculates an expected value of loss in a target index using the estimated error distribution; obtains an optimal stored hot water heat amount minimizing the expected value; and controls the heat pump unit so that the hot water storage tank stores the optimal stored hot water heat amount.

An apparatus and system for efficiently and safely transferring heat from a masonry heater to an external heating device using coil pipes and a liquid circulation pump. Circulation of a heat transfer liquid in the apparatus and system is controlled based on the measured temperature of the heat transfer liquid in the coil pipe on a return side of the masonry heater. Two additional sensors near the external heating device are used to control the flow rate of the circulation of the heat transfer liquid in the apparatus and system, thereby controlling the amount of heat actually transferred to the external heating device.

An apparatus and system for efficiently and safely transferring heat from a masonry heater to an external heating device using coil pipes and a liquid circulation pump. Circulation of a heat transfer liquid in the apparatus and system is controlled based on the measured temperature of the heat transfer liquid in the coil pipe on a return side of the masonry heater. Two additional sensors near the external heating device are used to control the flow rate of the circulation of the heat transfer liquid in the apparatus and system, thereby controlling the amount of heat actually transferred to the external heating device.

A multi-pipe-switching heat exchange apparatus has a heating module, an auxiliary module, a buffering module, and an operation module. The heating module has at least one heating boiler. The auxiliary module is deposited beside the heating module and has at least one spare boiler. The buffering module is connected to and communicates with the heating module and the auxiliary module, and has a buffering body connected to and communicating with the at least one heating boiler and the at least one spare boiler, a first pipeline set deposited between the buffering body and the heating module, and a second pipeline set deposited between the buffering body and the auxiliary module. The operation module is connected to and communicates with the buffering module and has an operation end and a third pipeline set connected to and communicating with the buffering body and the operation end.