A fluid heating system including a fluid supply subsystem having a fluid heating device, a fluid output subsystem, and an intermediary fluid device. The fluid heating system also includes a control device for the fluid supply subsystem, a first temperature sensor, a second temperature sensor, and a control circuit coupled to the control device. The control device is configured to control one selected from a group consisting of the fluid heating device and an amount of water input to the intermediary fluid device. The first and second temperature sensors are configured to output first and second temperature signals, respectively. The control circuit is configured to generate a first control signal based on the second temperature signal, determine a multiplier, generate a second control signal based on the first temperature signal, and send a main control signal to the control device based on the first and second control signals.

An air conditioning system having an auxiliary heat source is provided and that may include an outdoor unit, an indoor heat exchanger connected to the outdoor unit, the indoor heat exchanger including a temperature sensor, an auxiliary heat source arranged as an auxiliary to the outdoor unit and operated by an energy source different from an energy source of the outdoor unit, a thermostat configured to control a temperature of an installation space supplied with cold air or warm air by the outdoor unit and the auxiliary heat source, and a communicator. The communicator may include an input unit connected to the thermostat, a first output unit connected to the auxiliary heat source, a second output unit connected to the outdoor unit, and a controller configured to process signals between the input unit, the first output unit, and the second output unit.

A heating and hot-water supply device includes a combustion means, a heat exchanger, a circulation passage, a circulation means, a bypass passage, a distribution means, a hot-water supply heat exchanger, a water supply passage, a hot-water supply passage, and a control means. The heat exchanger heats a heating heat-medium to a target heat medium temperature. The distribution means distributes the heating heat-medium to the circulation passage and the bypass passage. The control means is capable of adjusting a distribution ratio of the distribution means to be adaptable to a heating operation, a hot-water supply operation, and a simultaneous heating and hot-water supply operation. At the time of transition from the heating operation to the simultaneous heating and hot-water supply operation, in a case where the heating terminal for performing heating is a warm air heater, the control means raises the target heat medium temperature.

A central controller for controlling power consumption in a thermal energy system is disclosed, the energy system may include a plurality of heat pump assemblies and a plurality of cooling machine assemblies, each heat pump assembly being connected to a thermal energy circuit comprising a hot conduit and a cold conduit via a thermal heating circuit inlet connected to the hot conduit and via a thermal heating circuit outlet connected to the cold conduit, each cooling machine assembly being connected to the thermal energy circuit via a thermal cooling circuit inlet connected to the cold conduit and via a thermal cooling circuit outlet connected to the hot conduit.

Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one alkali metal thermal-to-electricity converter (AMTEC) has a high pressure zone and a low pressure zone, the high pressure zone being thermally couplable to the at least one burner, the low pressure zone being thermally couplable to the heat exchanger.

Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one alkali metal thermal-to-electricity converter (AMTEC) has a high pressure zone and a low pressure zone, the high pressure zone being thermally couplable to the at least one burner, the low pressure zone being thermally couplable to the heat exchanger.

A high turndown furnace for an air handling system. In one example, the furnace includes a plurality of tubes divisible by four with a first modulating valve supplying gas to ¼ of the tubes and a second modulating valve supplying gas to ¾ of the tubes. In one aspect, the furnace is capable of providing a 16:1 turndown. In one aspect, the furnace is capable of providing seamless turndown operation throughout the entire firing range.

A hot water supply device includes a heater, a water channel, a mixing valve unit, and a circulation mechanism. The mixing valve unit has a valve member and a drive unit configured to drive the valve member to change a mixing ratio of supply water heated by the heater and unheated water. The circulation mechanism has: a connection passage that connects the water channel to the heater by being branched from a part of the water channel between the mixing valve unit and the heater; an on-off valve that opens and closes the connection passage; and a pump configured to return the supply water remaining in the water channel through the connection passage to the heater. A drive amount acquisition unit acquires a drive amount of the drive unit, and a controller controls the circulation mechanism based on the drive amount acquired by the drive amount acquisition unit.

A water preconditioner system comprising a user interface for manually or automatically receiving inputs from a user, a mixing assembly including a plurality of control valves coupled to hot and cold water supply lines, and a controller in communication with the plurality of control valves and the user interface for controlling the operation of the system. The controller is configured to operate in a plurality of modes to precondition the water to one of a desired preset water dispensing temperature or a target temperature different from the desired preset water dispensing temperature.

Heat pump system comprising a heat medium circuit (210, 220, 230, 240, 250, 310, 320, 410, 420, 430, 440, 450, 460) in turn comprising a compressor (211), an expansion valve (232, 242), at least one primary heat exchanging means (422, 433, 452) between a primary-side heat medium and a respective primary heat source or sink selected from outdoor air, a water body or the ground, at least one secondary heat exchanging means (314, 315, 316) between a secondary-side heat medium and a respective secondary heat source or sink selected from indoors air, pool water and tap water, and a control means (500). The invention is characterised in that the speed of the compressor can be controlled, in that an opening of the expansion valve is adjustable, in that the speed of the compressor is controlled, and in that an output temperature of heat medium flowing out from the expansion valve is controlled by controlling the opening of the expansion valve given the controlled speed of the compressor. The invention also relates to a method.