What does a bimetal flame sensor do?

A bimetal flame sensor is specifically designed to prove the existence of a pilot flame. This device typically consists of two different types of metals that are bonded together. When heated by the presence of a flame, the bimetallic strip bends due to the differing expansion rates of the two metals. This bending action can either mechanically or electrically signal that a flame is present, which is crucial for safety in gas appliances.

The primary function of the sensor is to ensure that there is an active pilot flame before allowing gas to flow to the main burner. If the pilot flame is extinguished, the bimetal flame sensor will detect this condition and can trigger a safety mechanism to shut off the gas supply, preventing the risk of a gas leak or explosion.

The other functions listed as options do not accurately describe the role of a bimetal flame sensor. For instance, while it can indirectly contribute to safety by enabling or disabling gas flow based on flame detection, its main purpose is not to monitor temperature, ignite the pilot light, or directly control gas flow without first confirming flame presence.