What type of draft fan is located between the chimney and the boiler furnace?

An induced draft fan is designed to create a negative pressure in the furnace, helping to draw gases through the combustion process and ensure that flue gases are effectively vented out of the boiler. By being positioned between the chimney and the boiler furnace, this fan aids in removing exhaust gases from the combustion chamber after the fuel has been burned.

This type of fan is crucial for maintaining safe and efficient operation of the boiler system because it ensures that the necessary airflow is present, allowing for proper combustion while also facilitating the expulsion of spent gases. Proper operation of an induced draft fan is essential in achieving optimal efficiency and preventing any back drafts that might compromise the combustion process.

In contrast, other options like forced draft fans are typically located before the combustion chamber to push air into it, while combustion air fans are primarily designed to supply air for combustion rather than to manage exhaust flow. Exhaust fans have a different application as they usually deal with ventilating spaces rather than managing the draft conditions in a boiler system.