A fuel nozzle assembly includes one or more tapered fuel nozzles. Each tapered fuel nozzle includes an acute trailing edge or tip at a top portion of the fuel nozzle. One or more fuel orifices are arranged proximate the acute trailing edge or tip. A tapered fuel nozzle having a toroidal airfoil structure includes a fuel channel to distribute a fuel to the fuel orifice(s). The fuel nozzle assembly may be provided as part of a burner system, including a perforated flame holder, and associated method, in which the fuel nozzle assembly is oriented to direct fuel form the fuel orifices toward the perforated flame holder.

The invention relates to a water heating device, comprising a burner (20) and a flame current measuring device (100) for measuring a flame current, which measuring device comprises two electrodes and a voltage source (14), wherein each of the poles (18, 19) of the voltage source is connected to one of the electrodes. The water heating device further comprises a heat exchanger (40) which is electrically insulated relative to the burner. The burner and the heat exchanger here form the electrodes of the flame current measuring device. The heat exchanger functioning as electrode can be earthed (41). The measured flame current can be used to determine the excess air factor of the combustion. The water heating device can further comprise an air/fuel controller for controlling the air/fuel ratio, wherein the air/fuel controller uses the determined excess air factor to control the air/fuel ratio. The invention also relates to a method for measuring a flame current in a flame.

A method for determining an change in an operating condition of a gas burner appliance. In some instances, a calibration of a gas/air mixture may be performed when the combustion quality of the gas burner appliance diminishes. This may be accomplished by adjusting a throttle position of a throttle valve that throttles the gas to the gas burner appliance. After calibration has been performed, a throttle position of the throttle valve is determined, and based on the throttle position determined after calibration, a change of an operating condition of the gas burner appliance is detectable.

A method for regulating the combustible mixture such as air/gas, air/methane gas or the like fed to a burner, the method including measuring a flame signal correlated with the composition of the mixture fed by feed members controlled by a combustion controller arranged to regulate the combustion on the basis of the flame signal. During burner operation the mixture feed conditions are modified within a narrow time interval to obtain a flame signal variation; a ratio between values of this the flame signal at the end and at the beginning of the interval is compared with a predetermined reference value; and, on the basis of the deviation of this ratio from the reference value, the flame set point is regulated, as consequently is the air or gas of the mixture if this is rendered necessary.

This invention relates to the field of sensing flames in equipment using a combustion burner such as gas furnaces by using the electrical properties of flames. In a first group of embodiments flame rectification is used to cause distortion of a signal having a selected waveform. A harmonic of the distorted waveform is detected thereby providing flame proof. In a second group of embodiments flame rectification is used as a mixer to cause two signals having selected waveforms to produce sum and difference signals. The sum and/or difference signals are detected thereby providing flame proof.

A flame sensor assembly includes a flame sense rod and a flame sensor body. The flame sense rod includes a flame sensor end and a coupling end opposite the flame sensor. The flame sensor body defines a receptacle for receiving the coupling end of the flame sense rod, and includes an adjustable positioning bracket. The assembly also includes a wiring adapter for connecting the flame sensor body with a flame sense signal connector, and a mounting bracket adapted to mount the flame sensor body to a heating device with the flame sensor end of the flame sense rod positioned adjacent a flame of the heating device. Methods of replacing a flame sensor assembly for a heating device are also disclosed.

A device for igniting/re-igniting the flame for a gas burner, for example for a cooktop, is capable of receiving a supply voltage from a supply source. The device is furthermore configured for receiving a signal representing the presence of the flame. The flame ignition/re-ignition device is configured for activating a spark activation circuit (70) configured for generating sparks for igniting the flame when the signal representing the presence of the flame indicates absence of flame, and interrupting the generation of sparks when the signal indicates presence of flame. Furthermore, the flame ignition/re-ignition device comprises an anti-inversion circuit (40) configured for uncoupling the flame ignition/re-ignition device from the direction of insertion of a supply plug for the device into a domestic power outlet, making the device insensitive to the polarity adopted in the connection between the plug and the power outlet.

The present description discloses a combustion type water heater that heats water by burning fuel. The combustion type water heater includes: a burner that generates combustion gas by burning the fuel; a heat exchanger that exchanges heat between the water passing through on an inside of the heat exchanger and the combustion gas flowing on an outside of the heat exchanger, an exhaust pipe that discharges the combustion gas after the heat exchange in the heat exchanger as exhaust gas; an exhaust gas temperature detector that detects a temperature of the exhaust gas flowing in the exhaust pipe as an exhaust gas temperature; a clog degree detector that detects a degree of clog in the exhaust pipe; and a scale buildup determiner that determines whether or not scale has built up inside the heat exchanger based on the exhaust gas temperature and the degree of clog in the exhaust pipe.

A gas burner system includes a gas burner through which an air-gas mixture is conducted; a variable-speed forced-air device that forces air through the gas burner; a control valve that controls a supply of gas for mixture with the air to thereby form the air-gas mixture; an electrode configured to ignite the air-gas mixture and produce a flame, wherein the electrode is further configured to measure an actual flame strength of the flame; a controller; and an input device for inputting a calibration command to the controller. Upon receipt of the calibration command, the controller is configured to automatically calibrate and save the target flame strength set point and thereafter automatically regulate a speed of the variable-speed forced-air device to cause the actual flame strength to achieve the target flame strength set point. Corresponding methods are provided.

A water heater monitoring and notification method includes determining that an intake pressure switch of a combustion system of a water heater or an exhaust pressure switch of the combustion system of the water heater is open and shutting down a blower of the combustion system in response to the intake pressure switch or the exhaust pressure switch being open.