This gas fired boiler offers good hot water heat for those cold winter days. Hot water heating is very popular and is considered to give the space even heat throughout the space. This hot water gas boiler can also be expected to provide at least thirty years of good heat as long as a good boiler preventive maintenance plan is in place for this hot water boiler. Looking at the front of this boiler you will see a motor in front of the boiler. This is a blower motor to blow combustion air into the boiler combustion chamber for the combustion process. When this boiler is started the boiler technician sets the amount of combustion air the combustion chamber receives from this blower by adjusting some air vanes where the air is sucked into the combustion chamber. It is a part of the process of starting up this hot water gas boiler and is a part of adjusting the gas manifold pressure and other factors that effect efficiency for this hot water boiler.