Lennox 13H27 Electrode Sensor

The Lennox 13H27 Electrode/Sensor is a safety component in different Lennox HVAC systems such as gas furnaces and oil-fired boilers. It also has the function of a security guard because it identifies the presence of a flame. The sensor produces a little current each time it makes contact with the ions in the flame. This current signal is then taken to the furnace control board to confirm the safety of the burner. If the flame is put off or fails to operate properly, the sensor does not get the current and the control board turns off the gas supply for safety purposes.