What is a requirement for the draft fan used to increase low draft conditions?

The requirement that the burner must shut off if the fan fails is crucial for safety reasons. In situations where a draft fan is being utilized to improve low draft conditions, maintaining proper airflow is essential for safe combustion. If the draft fan malfunctions or stops working, inadequate air supply can lead to the buildup of harmful gases, including carbon monoxide, or cause incomplete combustion, which poses significant risks of fire and poisoning.

By mandating that the burner shuts off in the event of a fan failure, this rule ensures that the system can prevent hazardous situations from arising. This safety mechanism serves to protect both the equipment and the occupants within the building by ensuring that there is no operation of the burner under unsafe conditions. It emphasizes the significance of reliable operation and monitoring in fuel-burning systems, highlighting the interconnectedness of air supply and combustion safety.