An automatic pilot lighting system for unattended automatic lighting of a standing pilot may include a powered (e.g., battery powered, etc.) circuit. The powered circuit may include an analog timer circuit including a timer switch. A spark ignitor may be coupled with the timer switch. A temperature knob pilot momentary switch may be coupled with the timer switch. An ON/OFF switch may be coupled with the temperature knob pilot momentary switch and the timer switch. The ON/OFF switch may be configured to be operable for selectively disabling and enabling a power source. The analog timer circuit may be configured to be selectively activatable for applying voltage from the power source via the ON/OFF switch for pilot hold voltage and spark ignition for an amount of time sufficient to allow for unattended automatic lighting of the standing pilot and sufficient voltage generation to support standalone operation.

A gas burner controller adapter for use in adapting a gas burner control device, which is configured to be connected to a flame ionization electrode and a separate ignition electrode, to operate in a gas burner that only includes a single electrode serving as both the flame ionization electrode and the ignition electrode.

A dual-gas source gas control system with anti-gas source misconnection and a control circuit thereof belonging to the gas combustion technical field are provided. The disclosure solves unreasonable design and other problems in the related art. The dual-gas source gas control system with anti-gas source misconnection and the control circuit thereof includes a power-on circuit, connected in series with an external power supply and an igniter switch to form a loop, including a self-locking switch triode connected in series with the external power supply and a self-locking amplifying triode connected to a base electrode of the self-locking switch triode; an MCU control circuit, including an MCU control chip, wherein the power-on circuit is connected to a power input pin of the MCU control chip, one pin on the MCU control chip is configured to detect whether the power-on circuit is connected.

A water heater control system comprising an energy storage system electrically connected to a pilot valve operator and electrically isolated from a main valve operator. The energy storage system may be electrically connected to an ignition circuit. A thermoelectric device is in thermal communication with the pilot flame and electrically connected to a main valve operator. The water heater system may include a microcontroller configured to establish electrical communications between the device and the energy storage system, the pilot valve operator, and the main valve operator. The microcontroller may be configured to recognize a call for main burner operation, and may also be configured to check an available voltage of the energy storage system against a setpoint. The microcontroller may establish pilot flame operation with or without main burner operation, depending on whether a call for heat or recharging of the energy storage system is required.

A start system for an expendable gas turbine engine is provided. The start system may include: a tank configured to store a pressurized gas comprising oxygen; a non-pyrotechnic igniter in communication with a combustion chamber of the expendable gas turbine engine; a starter tube configured to feed the pressurized gas from the tank into the combustion chamber; and a valve configured to regulate a flow of the pressurized gas from the tank into the starter tube; wherein, the start system is configured to startup the expendable gas turbine engine by the flow of the pressurized gas from the tank, through the valve and the starter tube, into the combustion chamber and, from the combustion chamber, into a plurality of turbine blades of the expendable gas turbine engine, and by ignition, by the non-pyrotechnic igniter, of fuel injected into the combustion chamber.

Methods and apparatus to indicate presence of a flame are disclosed. An example gas grill includes a burner tube having apertures to emit a fuel for combustion, an ignition element to cause ignition of the fuel emitted from the apertures of the burner tube, a flame sensor to detect the presence of a flame associated with the combustion of the fuel emitted from the apertures of the burner tube, and flame sense circuitry including a flame signal accessor to access a flame sense signal from the flame sensor, and a terminal to output an indication of the presence of the flame, the indication of the presence of the flame output without respect to an open or closed state of a lid of the grill.

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.

A means of detecting the in-situ fuel-to-air-ratio (FAR) in a combustor or flame zone using a Fourier-based flame ionization probe is presented. The use of multiple excitation frequencies and its detection at certain frequencies or combinations of harmonics of those excitation frequencies, namely, the inter-modulation distortion, provides a novel means of extracting a high signal-to-noise ratio (SNR) FAR measurement in a combustor.

A dual-gas source gas control system with anti-gas source misconnection and a control circuit thereof belonging to the gas combustion technical field are provided. The disclosure solves unreasonable design and other problems in the related art. The dual-gas source gas control system with anti-gas source misconnection and the control circuit thereof includes a power-on circuit, connected in series with an external power supply and an igniter switch to form a loop, including a self-locking switch triode connected in series with the external power supply and a self-locking amplifying triode connected to a base electrode of the self-locking switch triode; an MCU control circuit, including an MCU control chip, wherein the power-on circuit is connected to a power input pin of the MCU control chip, one pin on the MCU control chip is configured to detect whether the power-on circuit is connected.

A means of detecting the in-situ fuel-to-air-ratio (FAR) in a combustor or flame zone using a Fourier-based flame ionization probe is presented. The use of multiple excitation frequencies and its detection at certain frequencies or combinations of harmonics of those excitation frequencies, namely, the inter-modulation distortion, provides a novel means of extracting a high signal-to-noise ratio (SNR) FAR measurement in a combustor.