A heat pump may include a compressor configured to compress a refrigerant, a first temperature sensor configured to detect an outdoor temperature, a second temperature sensor provided in heating pipes connected to a heating device that performs indoor heating and configured to detect a temperature of fluid flowing through the heating pipes, an outdoor heat exchanger configured to perform heat exchange between outdoor air and a refrigerant, a third temperature sensor configured to detect a temperature of the outdoor heat exchanger, and a controller. The controller may be configured to: control power to a boiler and/or to the compressor based on sensing values of the first, second, and third temperature sensors, calculate an expected efficiency of the heat pump based on the sensing value of the first temperature sensor and an initial target temperature, and control power to the boiler based on the expected efficiency.

A heat pump may include a compressor configured to compress a refrigerant, a first temperature sensor configured to detect an outdoor temperature, a second temperature sensor provided in heating pipes connected to a heating device, and a controller. Based on a first sensing value of the first temperature sensor, the controller may be configured to control a compressor, control power to a boiler, and/or calculate an expected efficiency of the heat pump. Based on the expected efficiency and/or a second sensing value of a second temperature sensor, the controller may be configured to control power to the boiler.

A supply-water warming system includes a steam compression heat pump circuit, a heat recovery heat exchanger, a heat source fluid line in which heat source fluid flows in the heat recovery heat exchanger and the evaporator in this order, a water supply line in which supply water flows in the heat recovery heat exchanger and the condenser in this order, a refrigerant flow rate adjustment section controlled based on the superheat degree of gas refrigerant flowing into the compressor and configured to adjust a refrigerant flow rate, a supply water flow rate adjustment section controlled based on the tapping temperature of the supply water flowing out of the condenser and configured to adjust a supply water flow rate, and a control section configured to control the refrigerant flow rate adjustment section and the supply water flow rate adjustment section.

A water heater system includes a gas burner configured to selectively produce flue gases, and a heat exchanger for heating water in the water heater system. The water heater system is operable in a heating mode, and a standby mode. An exhaust assembly is in communication with the heat exchanger, and includes a condensate collector configured to receive the flue gases and condensate. A first temperature sensor is positioned to sense a temperature of the condensate within the condensate collector. The first temperature sensor is configured to detect a rate of temperature change of the condensate. A controller is configured to determine a leakage when the rate of temperature change adjusts from a first state to a second state when the water heater system is in the standby mode after the water heater system was in the heating mode.

A fired heater has two cells segregated by an insulative wall. A first plurality of burners are located in the first cell and a second plurality of burners are located in the second cell. A radiant tube extends from the first cell to the second cell for carrying a fluid material through the heater to heat the fluid material. The flow of fuel to the burners in either the first cell or the second cell can be terminated to accommodate lower heater duty when demand is lower.

A water heater system includes a water heater having a first water outlet and a second water outlet. The water heater system further includes a flow detection device coupled to the first water outlet to detect a water flow through the first water outlet. The water heater system also includes a flow control valve fluidly coupled to the second water outlet. The flow control valve is configured to control a flow of water through the second water outlet based on whether the water flow through the first water outlet is detected by the flow detection device.

A heat pump apparatus includes a use-side heat exchanger that causes heat exchange to be performed between a heat medium flowing from a heat-storage heat exchanger and a heat usage medium, and a flow-passage switching device that switches a flow passage for the heat medium to a first flow passage that circulates through a heat-reception-side heat exchanger and the heat-storage heat exchanger without extends through the use-side heat exchanger or a second flow passage that circulates through the heat-reception-side heat exchanger and the heat-storage heat exchanger via the use-side heat exchanger. Even when the temperature of the heat storage medium rises, heat received from a heat source can be stored in the heat storage medium by a heat pump, while a decrease of the efficiency of the heat pump can be reduced.

An electrode boiler control apparatus includes a control circuit formed in an electrode boiler in which an intake electronic valve and an exhaust electronic valve in addition to an intake control valve and an exhaust control valve corresponding to air control valves formed at both sides of an upper portion of the electrode boiler, connected to the intake electronic valve and the exhaust electronic valve to control the intake electronic valve and the exhaust electronic valve; a current controller connected to a current transformer connected between electrode bars of the electrode boiler to control the current transformer; and a temperature controller connected to a temperature sensor formed on a hot water tank of the electrode boiler, and configured to control the temperature sensor and receive a temperature value measured by the temperature sensor.

The present invention improves the user-friendliness of a hot-water supply apparatus when using hot water supply and air conditioning. A switching control unit 27, which switches between heat medium flow paths 4 and 5 according to an air conditioning ready state or a hot-water supply ready state, switches a heat medium flow path to the hot-water supply ready state by a switching valve 21 in the case where air conditioning is not used by the time an air conditioning standby time elapses during standby in the air conditioning ready state.

A heating and hot-water supply apparatus performs a heating operation by heating a heating medium with a heater and circulating the heating medium through a heating terminal, a hot-water supply operation by circulating the common heating medium through a hot-water supply heat exchanger, heating service water through heat exchange with the heating medium, and supplying hot water, and a simultaneous operation of the heating operation and the hot-water supply operation, and controls a distribution ratio of the heating medium between the heating terminal and the hot-water supply heat exchanger. The apparatus determines whether the heating terminal proceeding in the heating operation is a suspendible terminal to suspend the heating operation or an unsuspendible terminal not to suspend the heating operation in response to a request for the hot-water supply operation.