If it has any other usage other than supplying air to the combustion chamber? Will it play any role in allowing a quantity of air to the stack for clearing the exhaust?
yes it help to keep the exhaust exhausting by creating positive pressure in the stack. I am assuming you had problems with negative pressure and it backing up and shutting down your boiler? Forced draft: Draft is obtained by forcing air into the furnace by means of a fan (FD fan) and ductwork. Air is often passed through an air heater; which, as the name suggests, heats the air going into the furnace in order to increase the overall efficiency of the boiler. Dampers are used to control the quantity of air admitted to the furnace. Forced draft furnaces usually have a positive pressure. Thats the definition, But yes it provides the combustion air if you have limited breathing room for you boiler , and keep the positive pressure in your stack.
This Site Might Help You. RE: what is the purpose of a forced draft fan in a boiler? If it has any other usage other than supplying air to the combustion chamber? Will it play any role in allowing a quantity of air to the stack for clearing the exhaust?
FD Fan supplies with air into the boiler. That's what it does, Big time and almost all its life time. Remember that the furnace has high pressure(due to temperature) and its hard or almost impossible for the air way into the boiler without being pressurized hence the FD fan is installed. And again, This whole thing of clearing the exhaust I will presume you mean making the smoke much clearer appearance wise, well it depends. If you run on access air(supplying more are by adjusting your dumpers then the exhaust will be much clearer but believe me you don't wanna run too much excess air into your boiler. It chows efficiency big time, trust me.
