A flow heater for new forms of vehicles. The flow heater comprises a passageway for liquid, a heating source, a swing mechanism arranged in the passageway, and a sensor for detecting a position of the swing mechanism. In some embodiments, the swing mechanism includes a flap and a stopper wherein the flap is hinged to an inner wall and the stopper is fixed to an inner wall and located to abut the flap in the absence of flow.

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.

An apparatus includes a high-pressure tank, a controller, a valve, controlled by the controller, and a heater.

The present application provides a water flow heating device with a protection function, including: a heating cylinder, a heating wire disposed in the heating cylinder and a water flow temperature sensor, and a protection circuit respectively connected with the heating wire and the water flow temperature sensor; the protection circuit includes a first voltage comparator, an environmental thermal conductivity detection circuit for detecting an environmental thermal conductivity of the water flow temperature sensor and a protection switch for switching on and off the heating wire; the water flow temperature sensor is connected with an input terminal of the first voltage comparator and the environmental thermal conductivity detection circuit, respectively; an output terminal of the first voltage comparator is connected with the protection switch; and the environmental thermal conductivity detection circuit is connected with an enable terminal of the heating wire. The present application can prohibit the heating wire from being turned on when the water flow is not full or slow, and can also cut off the power supply of the heating wire when an internal temperature of the heating cylinder is too high, thus improving the stability and safety of equipment operation.

An HVAC system with a refrigerant gas sensor is provided. In one embodiment, an HVAC system includes a heat exchanger coil installed within a housing. The heat exchanger coil is operable to exchange heat with air in the housing via a refrigerant passing through the heat exchanger coil. The system also includes an HVAC sensor assembly installed within the housing. The HVAC sensor assembly includes a refrigerant gas sensor and an orientation sensor positioned to detect an orientation of the refrigerant gas sensor. The HVAC system may also or instead include a position sensor to detect the position of the refrigerant gas sensor within the system. Additional systems, devices, and methods are also disclosed.

A method of operating a gas heater for water including the steps of restricting a water flow to the gas heater; determining a first rate of a first gas heating for the restricted water flow; adjusting the gas heating to the restricted water flow; repeating the previous steps until a heated water has a temperature above a temperature threshold; removing the restriction to the water flow to increase the water flow; and determining a second rate of a second gas heating for the increased water flow.

In an electric water heater having adjustable set point and differential temperatures, upper and lower heating elements, and associated temperature sensors respectively operative to sense upper and lower tank water temperatures, a specially designed control system is provided for controlling the heating elements. The control system is operative to prevent dry firing of the heating elements by measuring temperatures over time with the temperature sensors.

Disclosed is a system and method for monitoring hot water supply in a load control network, and more particularly for ensuring that there is sufficient hot water available for a customer participating in a demand response program that uses, at least in part, water heaters as a component of the demand response program. A multi-meter that is external to the water heater is used to monitor an electrical power supply circuit on the water heater, to report preferably volts, amps, and power factor of the water heater. The multi-meter may use these measured values to, in turn, determine a current charge state of the water heater and thus ensure maintenance of an adequate supply of hot water, even in times of demand response curtailment.

A water heating apparatus includes a sensor to detect an inflow water amount flowing into the water heating apparatus, and a controller to determine connection or disconnection between the water heating apparatus and a water storage tank, based on the inflow water amount flowing into the water heating apparatus for a preset time duration. Thus, the water heating apparatus determines whether or not the water storage tank is connected thereto based on the amount of inflow water introduced into the water heating apparatus. Then, the water heating apparatus determines the operation mode of the water heating apparatus based on the determination result. Thus, even when the user incorrectly sets the operation mode of the water heating apparatus, the water heating apparatus may actively and correctly operate.

A gas valve for a gas appliance of a gas burner system. The gas valve is connected to a gas source via a gas pipe. The gas valve is disposed with a check valve body, wherein the check valve body allows gas in the gas pipe to flow into the gas valve and prohibits the gas in the gas valve to flow into the gas pipe so the check valve body can thereby prevent the gas in the gas valve from flwoing back to the gas pipe. When gas in the gas pipe flows to to another gas appliance of the gas burner system, the gas flowing to another gas appliance does not mix with air in the gas appliance, thereby reducing the iginition time and enhancing the combustion efficiency.