Fresh-air inlet | Article about fresh-air inlet by The Free Dictionary
A vent connection to a house drain, on the building side of the main drain trap.
References in periodicals archive
Note the relative positions of the exhaust pipe and the fresh-air inlet
in this Beech Debonair's wing root.
* Moved the fresh-air inlet
to the top of the radiator shroud, eliminating a resonator and baffle
Like a pitot tube or any other fresh-air inlet
on the airframe, if enough ice accumulates at the right (wrong) spot, the opening will become obstructed.