What can be a cause for a saturated oil burner?

The correct answer identifies moisture contamination in fuel oil as a cause for a saturated oil burner. When moisture enters the fuel oil, it can lead to a variety of problems within the burner system. Water, which is denser than oil, can settle in the bottom of the fuel tank and make its way into the fuel lines, disrupting the combustion process. This moisture can cause inefficient burning, leading to a lower flame temperature and potentially causing the burner to become saturated.

Saturation in oil burners indicates that the burner is unable to maintain an optimal air-fuel mixture for efficient combustion, which results in incomplete burning of the fuel. This condition can lead to an increased risk of fuel accumulation and creates operational issues, including potential safety hazards.

In contrast, excess fuel flow tends to lead to a rich mixture that can cause high emissions or operational inefficiencies, while high draft pressure usually encourages proper combustion by ensuring that exhaust gases are quickly expelled. Dirty fuel lines are more likely to cause clogs or reduced fuel flow rather than direct moisture issues leading to saturation. Thus, moisture contamination is a crucial factor that can significantly impact the operation of an oil burner.