What is one sign of a clogged oil nozzle?

A clogged oil nozzle can significantly impact the burner’s operation, leading to a fluctuating flame or excessive smoke. When the nozzle is blocked, it cannot properly atomize the oil, which is essential for creating a stable and efficient flame. Instead of a steady combustion process, the burner struggles to maintain an even flame, which may result in visible smoke and an instability in combustion.

A steady and consistent flame would indicate that the nozzle is functioning correctly, while the absence of a flame would suggest a complete failure in fuel delivery, such as with a pump issue. Similarly, rapid cycling of the burner generally points to other problems, such as an issue with the thermostat or safety controls, rather than directly indicating a clogged nozzle. Thus, the fluctuation of the flame and the resulting smoke are clear signs of an obstruction within the nozzle, making it the most accurate indicator of potential clogging.