I am installing a kitchen fan about 9' away from the nearest external wall. The wall there is very narrow and all I can fit there is a dryer type vent that works with 4" round pipe. Also, my spacing behind the framing along those 9' allows me only about 4" of space.
Can I exhaust a kitchen fan through a 4" round pipe across 9' linear with only one 90° turn? I'm guessing kitchen fan ventilation is subject to more scrutiny because the fumes contain oils that settle along the pipe, presenting a cloggage (carbon monoxide) and fire hazards.