A method of defrosting a heat pump device including a water tank, a heat exchanger, an electrical heating element, an evaporator, a fan for the evaporator, and a control unit. In a first operating mode, the heat pump device is controlled to heat water inside the water tank. In a second operating mode, the electrical heating element is manually activated to additionally heat the water inside the water tank. In a third operating mode, the electrical heating element is automatically activating to heat the water in the storage tank if: the power supplied by the heat pump device to heat the water inside the water tank is not sufficient; if a time limit after activation of a deicing operation has lapsed; and/or if the number of times the deicing operation has been activated during a predetermined time interval exceeds a threshold value.

The disclosed technology includes an on-demand water heater which uses an electric heat source to heat the water. The on-demand water heater can have a low fluid capacity heating chamber which has an inlet and an outlet, an electric heat source for heating the water, and a controller to control the electric heat source and maintain the temperature of the water at a predetermined temperature setting. The on-demand water heater can be powered by a direct current power source. The on-demand water heater can also utilize a solar thermal system to provide additional heat to the water.

A heat pump assembly (100) arranged to be connected to a thermal energy circuit (300) comprising a hot conduit (302) configured to allow thermal fluid of a first temperature to flow therethrough, and a cold conduit (304) configured to allow thermal fluid of a second temperature to flow therethrough, the second temperature is lower than the first temperature, and a cooling machine assembly (200) arranged to be connected to a thermal energy circuit (300) comprising a hot conduit (302) configured to allow thermal fluid of a first temperature to flow therethrough, and a cold conduit (304) configured to allow thermal fluid of a second temperature to flow therethrough.

The disclosed technology includes systems and methods for operating a pool water heating system. The pool water heating system can include a heat pump, a supplemental heat source, a water temperature sensor, and a controller. The controller can be configured to receive water temperature data and, in response to determining that the temperature of the water is less than a threshold temperature, output a control signal to activate the heat pump. The controller can further determine an expected heating time that can be indicative of an amount of time required for the temperature of the water to be greater than or equal to the threshold temperature. The controller can also generate a heating schedule based at least in part on the expected heat time and a predetermined time of use. The heating schedule can be indicative of a heat pump operation time and a supplemental heat source operation time.

A flame sensor for a furnace of a heating, ventilation, and air conditioning (HVAC) system includes a sensor body and an electrically conductive member of the sensor body. The electrically conductive member is configured to be disposed within a flame region of a burner of the furnace and configured to receive electrical current from a controller of the furnace. The flame sensor also includes an anti-oxidation coating disposed on an outer surface of the electrically conductive member and configured to transmit the electrical current from the electrically conductive member. The anti-oxidation coating is configured to contact a flame produced by the burner and expose the electrical current to the flame.

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 heating system configured to be connected to a heating distribution system of a building. The heating system comprises a heat pump arrangement configured to heat a fluid; a stratified heat storage device configured to store the fluid at differentiated temperatures, a mixing arrangement; and a control device for controlling the heating system. The mixing arrangement is configured to subtract fluid from the heat storage device and to regulate the temperature of the fluid entering the heat distribution system and control the temperature of the returning fluid from the heating distribution system. The invention also relates to a method for controlling such a heating system, a computer program, a computer-readable medium, and a control device.

A rotary apparatus for inputting thermal energy into fluidic medium is provided, the apparatus comprises: a casing with at least one inlet and at least one outlet; a rotor comprising at least one row of rotor blades configured as impulse impeller blades arranged over a circumference of a rotor hub mounted onto a rotor shaft; at least one row of stationary nozzle guide vanes arranged upstream of the at least one row of the rotor blades, respectively; and at least one row of stationary diffuser vanes arranged downstream of the at least one row of the rotor blades, respectively. The apparatus is configured to impart an amount of thermal energy to a stream of fluidic medium directed along a flow path formed inside the casing between the inlet and the outlet by virtue of a series of energy transformations occurring when said stream of fluidic medium successively passes through the blade/vane rows formed by the nozzle guide vanes, the rotor blades and the diffuser vanes, respectively, wherein, in said apparatus, a space formed between an exit from the at least one row of diffuser vanes and an entrance to the at least one row of nozzle guide vanes in a direction of the flow path formed inside the casing between the inlet and the outlet is made variable to regulate the amount of thermal energy input to the stream of fluidic medium propagating through the apparatus. Related uses and a method for inputting thermal energy into a fluidic medium are further provided.

A rotary apparatus for inputting thermal energy into fluidic medium is provided, the apparatus comprises: a casing with at least one inlet and at least one outlet; a rotor comprising at least one row of rotor blades configured as impulse impeller blades arranged over a circumference of a rotor hub mounted onto a rotor shaft; at least one row of stationary nozzle guide vanes arranged upstream of the at least one row of the rotor blades, respectively; and at least one row of stationary diffuser vanes arranged downstream of the at least one row of the rotor blades, respectively. The apparatus is configured to impart an amount of thermal energy to a stream of fluidic medium directed along a flow path formed inside the casing between the inlet and the outlet by virtue of a series of energy transformations occurring when said stream of fluidic medium successively passes through the blade/vane rows formed by the nozzle guide vanes, the rotor blades and the diffuser vanes, respectively, wherein, in said apparatus, a space formed between an exit from the at least one row of diffuser vanes and an entrance to the at least one row of nozzle guide vanes in a direction of the flow path formed inside the casing between the inlet and the outlet is made variable to regulate the amount of thermal energy input to the stream of fluidic medium propagating through the apparatus. Related uses and a method for inputting thermal energy into a fluidic medium are further provided.

A method of controlling a heating system includes: obtaining, from a power supply source, information specifying an output modulation period during which power consumption by a heat pump unit is to be reduced; and controlling, based on the information obtained in the obtaining, an amount of heat generated by the heat pump unit. In the controlling, the heat pump unit is caused to generate a first amount of heat per unit time in a period other than the output modulation period, and generate a second amount of heat per unit time during the output modulation period, the second amount of heat being less than the first amount of heat.