An improved boiler apparatus having multiple resistive heating elements are provided with fixed resistances that can be rewired to allow dual voltage capability and at the same time, reduced watt density. For 120V operation, the large diameter 9-ohm coil is used alone to provide the lowest possible watt density. For 240V operation, all three heating coils are wired in series, creating a low watt density but high wattage heater.

A system for heating a first fluid flow from a first temperature to a second temperature, the system including a hot water supply line for receiving the first fluid flow at a first end and exhausting the first fluid flow at a second end; and a heating system including a heat engine, a thermal battery and a heat exchanger, wherein the thermal battery is configured to be replenished at a point of heat transfer by the heat engine and the hot water supply line is configured to receive heat from the thermal battery via the heat exchanger to elevate the temperature of the first fluid flow from the first temperature to the second temperature.

The disclosed technology relates to a solar water heating system including a tank configured to store heat transfer fluid, a solar collector in fluid communication with the tank, and a pump system in fluid communication with the tank and the solar collector. The pump system can include a first pump, a second pump, and a valve assembly. The valve assembly can direct the heat transfer fluid from an outlet of the first pump to the solar collector when the first pump is operating and can direct the heat transfer fluid from an outlet of the second pump to the solar collector when the second pump is operating. The first pump and the second pump can transfer the heat transfer fluid from the solar collector back to the tank when the first pump and the second pump are not operating.

An improved boiler apparatus having multiple resistive heating elements are provided with fixed resistances that can be rewired to allow dual voltage capability and at the same time, reduced watt density. For 120 V operation, the large diameter 9 ohm coil is used alone to provide the lowest possible watt density. For 240 V operation, all three heating coils are wired in series, creating a low watt density but high wattage heater.

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 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.

A heat pump water heater and systems and methods for its control. The systems are configured to heat water within a water storage tank of a heat pump water heater wherein a controller within the system is operatively connected to a plurality of heat sources including at least one electric heating element and a heat pump and sensors in order to selectively energize one of the plurality of heat sources. The controller is configure to process data representative of the temperature of water within the tank near the top of the water storage tank, and rate of water flowing out of the water storage tank, in order to automatically selectively energize the heat sources. The selection of heat sources by the controller is determined by a mode of operation selected by the user and the data processed by the controller in view of the selected mode of operation.

The application relates to an induction heating device having a housing and a fluid duct. The fluid duct is arranged in the housing and has a fluid inlet and a fluid outlet. Inside the housing is an induction element which generates an alternating magnetic field and which is separated from the fluid duct in a sealed manner by at least one wall. The device also includes at least one metallic areal heating element arranged in the fluid duct which can be heated by the alternating magnetic field.

A water heating system can include a water heater having a tank, an inlet line, and an outlet line, where the inlet line provides unheated water to the tank, and where the outlet line draws heated water from the tank. The water heating system can also include multiple sensing devices, where each sensing device of the plurality of sensing devices measures a parameter associated with the tank. The water heating system can further include a controller communicably coupled to the plurality of sensing devices, where the controller determines an amount of heated water in the tank based on measurements made by the plurality of sensing devices.

A system and method for heating concrete structures to either prevent the build-up of freezing precipitation or eliminate freezing precipitation on a top surface of the concrete structures. The system includes a heating assembly integrally formed with a concrete structure to apply thermal energy to the top surface of the concrete structure. Optionally, the heating assembly includes heating elements formed of carbon fiber tape. Following formation of the concrete structure, the heating assembly is configured for unified movement with the concrete structure. The system optionally includes a control assembly operatively coupled to the heating assembly. The control assembly selectively powers the heating assembly and can be configured for remote operation. In use, the control assembly can be selectively activated from a remote location to power the heating assembly and heat the concrete structure.