What is mechanical draft?

Mechanical draft refers specifically to the use of fans or other mechanical devices to generate airflow within a furnace or other combustion system. This method is essential for efficiently controlling the air supply needed for proper combustion and enhancing the overall performance of the heating system. Mechanical draft systems can actively draw or push air into the combustion zone, ensuring optimal mixing of fuel and air, which leads to better combustion efficiency, reduced emissions, and improved heat recovery.

The other options, although related to airflow and combustion processes, do not accurately define mechanical draft. Natural draft relies solely on temperature-induced convection without the use of fans, whereas filtering air pertains more to air quality management rather than the mechanical processes used in combustion. The mention of high-pressure steam is unrelated to the concept of draft in the context of airflow and combustion management. Hence, the use of fans to create airflow in the furnace accurately encapsulates the essence of mechanical draft.