A digital gas cooking appliance is disclosed. The digital gas cooking appliance has the ability of self-initiating an automatic calibration process to determine an optimum valve position to be used for an electromechanical valve when igniting a gas cooking element by performing a plurality of ignition sequences for the gas cooking element at a plurality of respective valve positions of the electromechanical valve. During each of the plurality of ignition sequences, a respective ignition duration between a start of the respective ignition sequence when an igniter is active and the electromechanical valve is open, and a flame is detected by a flame detector, may be determined.

Various embodiments include a combustion apparatus comprising: a facility for open- and/or closed-loop control of the apparatus; a combustion chamber; an actuator adjusting an air supply; and a combustion sensor in a region of a flame of the chamber. The controller stores a list of support points. A first air supply value is assigned to each support point. A drift test value and an index for ascertainment of a test result are assigned to each support point. The controller: generates a specified air supply; selects a support point as a function of the air supply; and decides on a test result using the index for the support point. To ascertain a test result: receives a signal from the combustion sensor; determines a new test result; ascertains a changed drift test value for the selected support point; and stores the changed drift test value as the drift test value.

A method of calibrating a furnace includes determining a first flame stabilization period for the furnace that avoids detachment of a flame from a burner within a burner box of the furnace, determining a second flame stabilization period that is longer than the first flame stabilization period and avoids emission of a combustion tone from the furnace, and configuring a controller of the same or another furnace to utilize a flame stabilization period that has a duration between the first and second flame stabilization periods. Each flame stabilization period commences upon ignition of a premixed mixture of air and fuel at the burner while an inducer fan operates within a first range of fan speeds, and terminates when the rotational speed of the inducer fan increases to a second range speeds that is greater than the entire first range.

Methods, systems, and circuitries are provided for detecting flame in a fuel oil burner. In one example, a method includes receiving a series of one or more light samples, each indicative of a level of light. When the fuel oil burner is operating in the flame expected mode, the method includes determining whether the values of the one or more of the light samples exceed a flame threshold; determining whether the values of the one or more of the light samples meet secondary criteria; determining that a flame is present when the values of the one or more light samples exceed the flame threshold and meet the secondary criteria; and determining that a flame is not present when the values of the one or more light samples are below the flame threshold or do not meet the secondary criteria.

A gas burner system and corresponding methods include 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.

A gas appliance comprises a combustion device, an ignitor, a gas valve, a blower, a detecting device, and a control device. A control method thereof comprises: the control device is operated in a detection mode in which the control device controls the ignitor to ignite and controls the gas valve as well as the blower to provide a fixed gas flow and a fixed air flow to the combustion device. After igniting the flames, the control device determines burning states detected by the detecting device; if matching a first state, the control device controls the gas valve and the blower in correspondence to a first control data of the first natural gas; if matching the second state, the control device controls the gas valve and the blower in correspondence to a second control data of the second natural gas. In this way, the gas appliance is suitable for burning natural gas generating various heating values.

A gas burner comprises an automatic firing unit for regulating or controlling an amount of gas supplied to the gas burner via a gas control valve and a lambda probe (1) arranged in the exhaust gas flow for measuring a residual oxygen content in the exhaust gas. A method for operating the gas burner comprises a first operating state in which the gas burner is operated in standard mode, wherein the residual oxygen content in the exhaust gas is regulated via the measured value of the lambda probe (1). According to the invention, in a second operating state, the gas burner performs a fault test on the lambda probe (1) involving the steps of: deactivating (S18) a supply of power to a pump cell (PZ) of the lambda probe (1); determining a present test voltage (h) of a measurement cell (NZ) of the lambda probe (1); comparing (S25) the present test voltage (h) with a predefined test setpoint voltage (i) and determining a difference; and if the difference exceeds a predefined limit value, performing a safety deactivation (S29); or if the difference does not exceed the predefined limit value, operating the gas burner in the first operating state.

A method for commissioning a gas valve assembly for controlling fuel flow to a combustion appliance. An example method for commissioning the gas valve assembly may include initiating a commissioning mode in the controller of the gas valve assembly. Once in the commissioning mode, inputting a user defined initial air to fuel (A/F) ratio, activating the combustion appliance, setting a burner load of the combustion appliance to a set burner load, inputting a desired A/F ratio for the set burner load, running the combustion appliance at the burner load with the desired A/F ratio, and observing the operation of the combustion appliance. The method may further include saving the desired A/F ratio for the set burner load to the controller of the gas valve assembly and exiting the commissioning mode.

An electronic control system for a power burner system for use with a heating appliance includes a burner tube, a gas valve for providing gas to the burner tube, an electronic control and a variable speed combustion air blower for mixing air with the gas provided to the burner tube. The electronic control system further includes a control in communication with the gas valve and the combustion air blower. The control may also be in communication with various other devices of an appliance, such as a variable speed air-circulating fan, a variable speed exhaust fan, or various sensors associated with the heating appliance. The control modulates the gas valve and the combustion air blower to maintain substantially stoichiometric conditions of the gas and air provided to the burner tube and as a function of signals from at least one of the devices. In one embodiment, the burner system may be used in a conveyor oven.

Boiler systems and associated control systems, methods for operating same, are described herein. In one example embodiment, a boiler system includes a furnace, an exhaust passage, an air passage, a FGR passage, a flue gas valve that is adjustable by way of a first actuator, a NO.sub.X gas sensor, an oxygen gas sensor, and an additional valve that is adjustable by way of a second actuator. Further, the boiler system includes at least one processing device coupled to the NO.sub.X gas sensor, the oxygen gas sensor, the first actuator and the second actuator. The at least one processing device is configured to generate control signals that are provided to the first actuator and second actuator, and also configured to generate correction factors by way of a calibration process and to utilize one or more of the correction factors in determining one or more of the control signals.