Example furnaces and methods related thereto include a burner box including at least one burner configured to combust a fuel/air mixture. In addition, the furnace includes a first blower including an inlet nozzle having an air inlet and fuel inlet. The inlet nozzle is configured such that operation of the first blower is to pull air and fuel into the inlet nozzle to produce the fuel/air mixture at a fuel/air ratio that is configured to produce flue products having less than 14 Nano-grams per Joule of nitrogen oxides when combusted. Operation of the first blower is configured to push the fuel/air mixture into the burner box. Further, the furnace includes a heat exchanger assembly fluidly coupled to the burner box through a vestibule, and a second blower configured to pull the flue products through the heat exchanger assembly.

A method for detecting a flame is provided. The method includes the step of providing alternating current to a flame rectification probe to produce a first voltage as an input for a sense circuit, wherein the flame rectification probe is placed in proximity to the flame. The method further includes the step of conditioning the first voltage using the sense circuit to produce a second voltage. Additionally, the method includes the steps of outputting the second voltage to a microcontroller, and determining with the microcontroller whether the flame is present based on a magnitude of the second voltage.

The present invention provides a gas valve and a control device and a control method thereof wherein the control device receives a detection voltage generated by a thermocouple. the control device outputs the second voltage when the detection voltage generated is greater than a predetermined voltage, and then outputs the first voltage. The control device stops outputting the first voltage when receiving a shut-off signal, and the control device starts counting time and stops outputting the second voltage when the time counted reaches a predetermined time.

The present disclosure provides a burner management system (BMS) for an industrial gas appliance and method for controlling a warm-up operation of the industrial gas appliance. The BMS and control method only requires a subset of the burners to be provided with flame detectors. In accordance with one aspect, the method involves lighting a supervised burner by providing a fuel gas flow thereto; continuously detecting a flame at the supervised burner indicating that the supervised burner is lit; incrementally lighting non-supervised burners by providing the fuel gas flow thereto when a non-supervised burner status indicates a safe lighting condition, the non-supervised burner status being determined by: measuring a total fuel gas flowing to the plurality of burners; and determining the number of the non-supervised burners with the fuel gas flowing thereto from the measurement of the total fuel gas and a supervised burner status.

Exemplary embodiments are disclosed of controls including circuit assemblies configured for determining igniter, inducer relay, and igniter relay faults. In exemplary embodiments, a control for a system includes an input configured to receive a control signal, an inducer relay, an igniter relay, and a circuit assembly. The circuit assembly is configured to be coupled to the inducer relay, the igniter relay, and an igniter of the system. The circuit assembly comprises a plurality of diodes and is configured to enable detection of and distinguishing between a failure of the igniter, a failure of the inducer relay, and a failure of the igniter relay as determined by a waveform of the control signal at the input of the control for a given one of a plurality of operational states of the control.

The present disclosure provides a burner management system (BMS) for an industrial gas appliance and method for controlling a warm-up operation of the industrial gas appliance. The BMS and control method only requires a subset of the burners to be provided with flame detectors. In accordance with one aspect, the method involves lighting a supervised burner by providing a fuel gas flow thereto; continuously detecting a flame at the supervised burner indicating that the supervised burner is lit; incrementally lighting non-supervised burners by providing the fuel gas flow thereto when a non-supervised burner status indicates a safe lighting condition, the non-supervised burner status being determined by: measuring a total fuel gas flowing to the plurality of burners; and determining the number of the non-supervised burners with the fuel gas flowing thereto from the measurement of the total fuel gas and a supervised burner status.

Systems, methods, and circuitries are provided for a controller for a fuel oil burner system that controls a fuel oil burner to perform intermittent ON cycles. In one example, a controller includes a memory configured to store a value for one or more burner control delay periods and a processor. The processor is configured to perform an auto-set procedure in a first ON cycle. The auto-set procedure includes detecting an oil valve in the fuel oil burner; determining that the value for a burner control delay period is a default value; and in response, storing a valve-present value as the value for the burner control delay period in the memory.

The invention relates to a method and a device for determining in a heating appliance whether ignition of the mixture of fluid fuel and air has taken place, comprising the following steps of: applying an electrical ignition signal to a measuring circuit; filtering a combustion signal from the ignition signal; comparing the detected combustion signal to a predetermined pattern; and establishing that the anticipated combustion signal took place during a predetermined period of time.

A locally powered intermittent pilot combustion controller may include an igniter, a thermal electric and/or photoelectric device that produces an electrical signal having power when exposed to a flame, and a local power source for providing power when the thermal electric and/or photoelectric device is not exposed to a flame. In some cases, the intermittent pilot combustion controller may include a memory for storing information about an ignition sequence for igniting a pilot flame, and a controller coupled to the memory. The controller may be configured to initiate the ignition sequence of the pilot flame using information stored in the memory, determine whether the ignition was successful by monitoring the electrical signal produced by the thermal electric and/or photoelectric device, and adjust the information stored in the memory based on whether the ignition sequence completed successfully.

A spark detector indicates the presence of a spark by analyzing sound waves generated when an electrical spark is produced from an electrical spark generator located on an igniter rod. The spark detector includes an acoustic sensor that is in communication with the igniter rod to determine the time for the spark sound wave to travel through the igniter rod to the acoustic sensor. If a spark is not detected, the spark detector may output a signal indicating at least one of (i) the spark was not detected, (ii) to replace the electrical spark generator immediately, or (iii) replace the electrical spark generator soon such as at the next scheduled maintenance. Furthermore, the spark detector may be calibrated based on current temperature of the igniter rod based upon time of propagation of a pulse sound wave, generated by a pulse-echo generator, to reflect off an end of the igniter rod.