What device ensures ignition in an oil burner system?

In an oil burner system, the cad cell plays a crucial role in ensuring ignition. The cad cell, or cadmium sulfide photoconductive cell, is a sensor that detects the presence of flame once the burner is ignited. It is sensitive to the light emitted by the flame. If for any reason the flame goes out, the cad cell will no longer receive light, and it will signal the combustion control system to shut down the burner to prevent any buildup of unburned fuel, which could lead to safety hazards or inefficiencies.

This functionality makes the cad cell essential for safe operation. It not only ensures that the burner lights properly but also monitors the flame during operation. If it detects that the flame has gone out, it takes action to prevent further fuel flow, effectively safeguarding the system.

Other devices, like the thermostat, are important for regulating temperature but do not directly ensure ignition. The combustion chamber is where the fuel and air mix and burn to produce heat, but it does not initiate ignition. The fuel pump is responsible for delivering oil to the burner, but it does not play a part in ensuring that ignition occurs once the burner has started.