A portable space heater includes a housing with an air inlet through which ambient air is received and an air vent through which heated air is expelled. A centrifugal fan of the heater is configured to drive air flow into the air inlet. A flow channel of the heater is configured to direct the air flow toward the air vent and a heating element heats the air flow in the flow channel. The heater additionally includes a sensor configured to sense proximity of a body part to the air vent and a controller configured to pause operation of the heating element based on the sensing, wherein the centrifugal fan, the flow channel, the heating element, the sensor and the controller are housed in the housing.

The present disclosure discloses a dynamic equivalent circuit of a combined heat and power system, and a working method thereof. Controlled sources are used to represent a thermoelectric coupling source; equivalent inductance is used to represent a delay of a heat transmission pipeline; equivalent resistance is used to represent a heat load and a heat loss of the heat transmission pipeline; and equivalent capacitance is used to represent a heat storage water tank. A circuit model is used to uniformly represent two thermoelectric heterogeneous energy sources, and a single power simulation tool may be used to simulate a combined heat and power system, so that the simulation system has a simple structure and is easy to develop and maintain.

Described is a liquid heater having a housing, in which a flow channel runs from an inlet to an outlet, a heating resistor arranged within the housing for heating liquid flowing through the flow channel, control electronics which are arranged in an interior space of the housing, the interior space being sealed off from the flow channel, and a plug connector attached to the housing. Provided according to this disclosure, the plug connector has a vent duct which is closed by a membrane and which leads to the interior space sealed against the ingress of liquid, in which interior space the control electronics are arranged.

A tankless water heater comprising a bare wire heating element is disclosed which is connected to an electronic temperature control system. At least one sensor is furthermore connected to the electronic temperature control system. A fluid heating chamber is made of insulating non conductive material wherein the heating element is located. At least one switch is connected to at least one bare wire heating element and to a phase of an AC line. An electrode system and an electronic detecting circuit are interconnected. The electrode system is arranged in a fluid channel, in a short distance from the bare wire heating element which acts like electrode 1. The electrode 2 of the electrode system is made from a conductive tube material hydraulically connected to a throttle valve made from non conductive material to insulate the electrode 2 from the grounded collector. The electrode 2 is electrically connected to a electronic control system via a conductive material.

A collection of methods for monitoring the operation of a heating system configured to heat a space is provided. One method includes obtaining, by one or more computing devices, data from a fuel sensor for a period of time, the fuel sensor configured to detect an amount of fuel within a fuel supply for a furnace of the heating system. The method further includes determining, by the one or more computing devices, an adjustment to the operation of the heating system based, at least in part, on the data obtained from the fuel sensor. The method additionally includes adjusting, by the one or more computing devices, the operation of the heating system according to the adjustment.

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 method of controlling water heater pilot flame ignition includes receiving, by a controller of a water heater, a user input and controlling a pilot gas valve to start a gas flow to a pilot burner in response to the user input. The method further includes, in response to the user input, controlling, by the controller, an igniter to generate an ignition spark for lighting a pilot flame. The method also includes controlling, by the controller, the pilot gas valve to maintain the gas flow to the pilot burner if the pilot flame is lit.

The present disclosure provides a driving part of a warm air heater and the warm air heater, wherein the driving part comprises a driving circuit board, and a silicon-controlled element is arranged on the driving circuit board; the driving circuit board is arranged in an air duct of the warm air heater, and the driving circuit board is positioned at the upstream of the heating part or is flush with the heating part, wherein the upstream or the flush is based on the direction of air flow in the air duct. The driving part of the present disclosure utilizes the fan to cool the silicon-controlled element without adding large-area radiating fins, thus reducing the cost of the driving part, and the driving circuit board is not arranged on the main control circuit board anymore, thus realizing the miniaturization of the main control part.

A sensor system includes a sensor and a plurality of panels connected to each other in a loop around the sensor. A duct is positioned to direct air towards the sensor. A heating element is disposed in the duct. First and second valves are disposed in the duct and spaced from each other along the duct. The first and second valves are selectively actuatable between an open position permitting airflow through the duct and a closed position blocking airflow through the duct. A computer is communicatively coupled to the heating element and the first and second valves. The computer is programmed to, upon determining a first difference between one respective panel temperature and an ambient temperature is greater than a first threshold, actuate the second valve to the closed position and maintain the first valve in the open position. The computer is further programmed to actuate the heating element to a first heating level based on the first difference.

A system for precision temperature control of thermal bead baths used in biological laboratories to heat biological samples. An insulated outer shell and an inner shell sealed together to form a recirculation pathway. The inner shell has an air extraction port opening into the recirculation pathway and at least one air injection port opening into the recirculation pathway. A fan in the recirculation pathway draws air through the air extraction port. A thermal sensor is connected to a control and is disposed in close proximity to one of the air injection ports. Thermal beads are placed in a mesh basket inside the inner shell. The fan draws air from the inner shell through the beads and into the recirculation pathway, where the air is heated by a thermal element. The air flows past the thermal element and through the air injection ports back into the inner shell.