What is the main function of a float switch in an oil burner?

The main function of a float switch in an oil burner is to measure the oil level. This device is designed to monitor the level of oil in the tank and control the operation of the burner accordingly. When the oil level falls below a certain point, the float switch will signal the burner system to shut off, preventing potential damage from running the burner dry. This safety mechanism is crucial in ensuring that the oil burner operates efficiently and safely without running out of fuel, which could lead to other complications including system failures or overheating.

Other options involve different functions that are not directly related to the float switch's purpose. For example, ensuring proper pressure relates more to pressure sensors or switches, which monitor the fluid's pressure in the system rather than the oil level itself. Igniting the burner is typically the job of an ignition system or spark plug, while regulating temperature is the function of thermostats or temperature sensors that monitor and control the burner’s heating output.