How much current does a typical flame sensor produce?

A typical flame sensor produces a current in the range of 30 to 200 microamps. This current is indicative of the sensor's ability to detect the presence of a flame. The operation of a flame sensor relies on the principle of flame rectification, where the ionization of the flame generates a small electrical current. Having the correct range is crucial for the safe operation of gas furnaces, as it ensures that the sensor can appropriately signal whether a flame is present or if there is a potential safety hazard, such as a flame failure. This range enables the furnace control system to react properly to maintain safe and efficient operation. Understanding the typical current range helps technicians diagnose issues with the sensor and ensures compliance with safety standards.