How does an induced draft fan operate in a boiler system?

An induced draft fan operates in a boiler system by creating a negative pressure that draws flue gases out of the boiler and exhausts them through the chimney. This function is critical for maintaining proper ventilation and combustion efficiency. By sucking air and exhaust gases out, the fan helps ensure that fresh combustion air can be introduced into the furnace while effectively removing combustion byproducts.

This operation is essential for optimizing the combustion process and enhancing the overall efficiency of the boiler. The induced draft fan also helps in maintaining the correct pressure within the boiler system, which is vital for safe operation.

While the other options represent different aspects of boiler operation and air management, they do not accurately describe the primary role of an induced draft fan, which focuses specifically on removing air and gases from the system to promote efficient combustion and safe exhaust handling.