A facility for control of a combustion apparatus comprising: a memory storing a limit value and a correction factor; a communication connection to a sensor and an actuator; and a processor. The processor: receives an input signal from the sensor; uses the signal to form a measured value specifying a fuel air ratio, an air ratio, and/or an oxygen content; and loads the limit value and compares the measured value with the limit value. If the measured value is less than or greater than the limit value, the processor either loads the correction factor and determines a correction value as a function of the limit value, the correction factor, and the measured value, or loads the stored correction value from the memory, and then creates an output signal as a function of the correction value and sends the output signal to the actuator.

Various embodiments include a combustion apparatus comprising: a control 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 control facility 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 gas-powered appliance includes a main burner for burning gas, a flame sensor assembly, and a controller. The flame sensor assembly includes a probe positioned proximate the main burner and a detector coupled to the probe to receive an alternating current (AC) input, couple the AC input to the probe and generate a variable pulse width direct current (DC) square wave output having a plurality of pulses. The controller connected is to the flame sensor assembly and includes a processor and a memory. The controller is programmed to control the main burner to burn gas, determine a pulse width of a pulse of the DC square wave, and determine based on the determined pulse width a characteristic of the flame on the main burner with greater precision than some known systems.