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In-Line Bathroom Fan

I am remodeling two bathrooms and I would like to put fans with heater and lights in the bathrooms. I have only seen 110 CFM rated fans and since the bathrooms are large I am thinking that installing an in-line fan that would be connected to both bathrooms would be appropriate.
Is there a way that I can control the in-line fan from the two bathrooms (where the individual bathrooms switch would also turn on the in-line fan also).

Re: In-Line Bathroom Fan

The simplest way to control the fan from either bathroom would be to use 3way switches / wiring arrangement between the rooms and fan.
The downside would be if the fan was turned on in one room the switch in the other room would also switch it off -- which also an upside.

Re: In-Line Bathroom Fan

My church has a similar setup, except that the fan is triggered by turning on the light in any restroom.

I believe the way it's configured is that a bank of relays (lighting contactors) is used. The light in each restroom is connected to the coil of a single relay. The "switch" side of the relays are wired in parallel so that if any relay is triggered by the light turning on, the fan comes on.

In this way, four restrooms share a single fan, and the fan runs only when needed. (The restroom lights in the church are motion controlled, so the lights shut off automatically when not needed.)

It also allows the lights and fan all to be on separate circuits if need be, and keeps one light from turning on all lights.

Re: In-Line Bathroom Fan

First of all the bathroom fan is used to remove warm moist air near the ceiling not to evacuate the entire room. That being said, Yes it can be done by using 2 relays however the in-line fan would be sucking air out of both bath rooms when it is on unless dampeners are also used and controlled by the relays. As Canuk said the simplest way would be to control the two fans with three way switches, one in bath room one and the other in bathroom two. Either switch would then turn on and off both fans at the same time or install two in-line fans, one for each bath room.


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