On Mar 3, 9:57 pm, "dave" nospam wrote:
I get a lot of dust in my house. I noticed the front panel on my furnace is
not even close to air tight. I can see through gaps and holes directly into
where the blower is (which is directly over the air filter). So the blower
is sucking in some air from the return line and through the air filter, but
a lot is coming through the gaps in the panel. Should I somehow seal this
panel better and force all air to come from my air return vent which is
located in the center hallway of the house? I don't understand this design
of a furnace which takes no care in keeping dirty air from the garage out.

Thanks,
DaveL

If you have gas or oil, you are "sucking" air into the furnace
room to support combustion and carry the fumes up the chimney.
When running, a combustion furnace attempts to pull a vacuum on the
whole house.

The fact that your furnace panel doesn't seal well doesn't affect that
whole house vacuum. It merely allows the furnace to draw air from the
furnace room and distribute it through the registers.

Building codes demand that garages be constructed to prevent garage
air from entering the house (when any connecting door is closed of
course). If you somehow know that "dirty garage air" is entering
your house, then you have a problem with the doors and walls, not
the furnace.

In any case, around here, outside air is "dirtier" than garage air.

You can seal the gaps in the panel if you wish. That will improve
the ability of your system to heat the upstairs rooms.

Jason