A double swirl burner including an annular air nozzle, an annular fuel nozzle coaxially disposed within the annular air nozzle, and a central air nozzle coaxially disposed within the annular fuel nozzle. An annular air nozzle may include at least one first inlet port on a peripheral wall of the annular air nozzle, where the first inlet port may be configured to allow for tangentially injecting a first air stream into the annular air nozzle. A first air stream may be tangent to a circular cross-section of the exemplary annular air nozzle, and a first axial inlet that may be configured to allow for axially injecting a second air stream into the annular air nozzle along a centerline of the annular air nozzle.

Methods and systems for controlling a gas valve assembly and/or combustion appliance may include identifying a flow rate of gas to a burner of a combustion appliance and determining if the flow rate is sufficient for a burner load of the combustion appliance. If the flow rate is sufficient for a burner load, a position of the valve member of the valve assembly and/or the burner load may be adjusted such that the flow rate of gas meets a target flow rate of gas for the current burner load. If the flow rate is insufficient to meet the current burner load, the valve member of the valve assembly may be positioned in a fully open position to at least partially meet the current burner load. If the flow rate is below a minimum flow rate threshold, the valve member may be moved to a fully closed position.

Described is a device for controlling a fuel-oxidizer mixture for a premix gas burner, comprising an intake duct, which defines a cross section for the passage of a fluid inside the duct and includes an inlet, a mixing zone and an outlet, an injection duct, connected to the intake duct in the mixing zone, a monitoring device, configured for generating a control signal, representing a combustion state in the burner, a gas regulating valve, positioned along the injection duct, a fan, positioned in the intake duct for generating therein an operating flow in an inflow direction, a control unit, configured to control the rotation speed of the fan, a regulator, coupled with the intake duct for varying the cross section. The control unit is configured for controlling the gas regulating valve in real time.

A method includes identifying a first steady-state gain associated with a relationship between a characteristic of a furnace and a setpoint used by a controller that is configured to control the characteristic of the furnace, The first steady-state gain is identified using data collected when the furnace is not suffering from flooding. The method also includes identifying a second steady-state gain associated with the relationship during operation of the furnace. The method further includes comparing the first and second steady-state gains and identifying actual or potential flooding of the furnace based on the comparison.

A gas burner system has a gas burner with a conduit through which an air-gas mixture is conducted; a variable-speed forced-air device that forces air through the conduit; a control valve that controls a supply of gas for mixture with the air to thereby form the air-gas mixture; and an electrode configured to ignite the air-gas mixture so as to produce a flame. The electrode is further configured to measure a flame ionization current associated with the flame. A controller is configured to actively control the variable-speed forced-air device based on the flame ionization current measured by the electrode so as to automatically avoid a flame harmonic mode of the gas burner. Corresponding methods are provided.

A method includes identifying a first steady-state gain associated with a relationship between a characteristic of a furnace and a setpoint used by a controller that is configured to control the characteristic of the furnace, The first steady-state gain is identified using data collected when the furnace is not suffering from flooding.

The method also includes identifying a second steady-state gain associated with the relationship during operation of the furnace. The method further includes comparing the first and second steady-state gains and identifying actual or potential flooding of the furnace based on the comparison.

A fuel regulator, such for use in a commercial boiler, can include a control valve plumbed between a source line and a feed line. The feed line can be coupled to a burner configured to burn fuel supplied thereto at a range of pressures and the source line can be coupled to a source of fuel configured to supply the fuel at a pressure higher than the range of pressures. One or more sensors can be configured to detect an operating level of the burner. One or more actuators can be configured to control the valve according to the sensor and thereby control a flame from the burner.

A water heater including a tank configured to hold a fluid, a burner configured to manipulate a temperature of the fluid within the tank, one or more sensors configured to sense one or more characteristics of the burner, a fuel injector position upstream of the burner, and a controller. The controller includes an electronic processor and a memory. The controller is configured to receive one or more signal from the one or more sensors corresponding to the one or more characteristics, and control the fuel injector based on the one or more signals.

A regulation device for regulating a mixing ratio (x) of a gas mixture comprises a first conduit (1) for carrying a flow of a first gas (e.g., air) and a second conduit (2) for carrying a flow of a second gas (e.g., a fuel gas). The first and second conduits (1, 2) open out into a common conduit (3) in a mixing region (M) to form the gas mixture. A first sensor (S1) is configured to determine at least one thermal parameter of the gas mixture downstream from the mixing region. A control device (10) is configured to receive, from the first sensor, sensor signals indicative of the at least one thermal parameter of the gas mixture and to derive control signals for adjusting device (V1) acting to adjust the mixing ratio, based on the at least one thermal parameter.

A gas meter includes a flow rate measuring part configured to measure a flow rate of gas flowing through a flow passage, a shutoff valve configured to shut off the flow passage, a wireless communicator configured to periodically perform wireless communication externally, and a communication interval setting part configured to set a communication interval in the wireless communication. The communication interval setting part is configured to set the communication interval according to the flow rate of gas measured by flow rate measuring part.