Also with the increasing concern of radon infiltration fresh air becomes an even greater need.
Fresh air intake into furnace room.
Fresh air is brought in from an outside intake hood and dispensed in the return air duct.
It is then heated by the furnace and distributed through the home.
In many homes the fresh air intake is simply an open duct ran from an outside vent into a basement or any room housing the home s furnace.
Many people erroneously close this one off because it freezes out the basement.
One brings air into the furnace room and dumps it on the floor.
Its function is to provide air for the furnace burner and chimney.
The indoor portion of your unit has an air conditioner return air intake usually located on the ceiling.
Some modern furnaces actually draw air from outside directly into the unit.
With today s homes being built increasingly airtight it is becoming essential to bring fresh air into the home mechanically.
This return air intake grille typically includes some type of filter to keep dust and debris out while allowing air to pass through.
So when you remove the filter from a return plenum in a gas furnace installation in a new home and look closely you ll likely note some kind of system that allows fresh air to be drawn directly from the outside and delivered into the return of the furnace cabinet.
Fresh air intakes can be in multiple locations throughout your home especially in newer homes built to modern building codes requiring homes to be much tighter than older homes.
Unfortunately the fresh air intake you have described is the second type and does not provide direct combustion air to the furnace room as it is directly connected to the return air plenum for.
The purpose of it is with the new homes and energy efficiency of the homes they are sealed so tight that it allows no fresh air to come into the furnace room area to allow fresh air to flow into.
In these cases an air intake will also be used.
There s also a separate fresh air intake which is currently covered with dry wall.
The grill allows air from the rest of the basement into the furnace room.
The air passes through the filter of the unit and quickly passes over the supercooled coils inside.
Without fresh air the home becomes stuffy and deadly combustion gases may build up.
There are often two separate vents that go to the outside for a forced air furnace.