In theory that would work as long as both fans aren't running at the same time. Each fan will have a flapper to prevent reverse air flow. But if they're both running, neither one will be able to push the air at full efficiency. :no:Can I couple the (2) 4" aluminum vents into 1 common 4" vent?
I agree for new construction or remodeling, but I must admit that for swap outs on service calls, I have run these myself. I usually duplicate the existing setup, unless they just vent into an attic.This is why the mechanical contractor should install the fart fans.
I was planning on doing it like I've always done it.... flexible aluminum.Mag - I've put a "y" connector right close to the exterior vent and then connected two runs into that. Kind of a last resort thing if they don't want two vents, etc.
Also, it's usually far enough down the run that backdrafting would not be a problem.
x2 with that Tin said about low spots. Also, think about insulated ducting if it is in an attic area.
I'll let an HVAC guy answer - just my opinion, but I do not like flexible aluminum - either ridgid or insulated.I was planning on doing it like I've always done it.... flexible aluminum.
Is that bad (really bad!) because the moisture meets the cold in air in the winter?