I am replacing my bath fan. The outlet of the fan is nominal 4:” (actual 3.75″) and the vent duct to which it is supposed to connect is nominal 3.5″ (actual 3.25″). Do I 1) get an adapter of some sort (and, if so, where)? 2) slice up the end of the duct to fit over the fan outlet and then use more duct tape than it would otherwise deserve? or 3) do something else? Thanks, Mark
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Replies
If possible find an adapter, but with the expanding aluminum (almost foil) duct material it's fairly easy to "gather" the duct arond a smaller one, with a "hose clamp".
the duct is smaller than the outlet of the fan, which means I need to expand the duct or find an adapter. Or something else. I'm reluctant to go slicing into the flexible duct, just to make it bigger to surround the outlet. But that might be my first and best shot at it.
I was thinking a short piece of the expandable stuff in the larger size, scrunched down on one end.
Barsh
There is available in most places that sell fans, a plastic reducer fitting.
or
An HVAC supply should be able to give you one in galvanized.
They'll call it a 4 to 3", but it will allow you to fit over it. I'd use the alum. foil tape for all connections. Peel and stick paper backing, also available from the above suppliers.
Get the other Fan
As you explained that your duct is smaller than fan so in my opinion you should expand the duct and if you cannot do so get the smaller fan for duct because no other option is there.
Mt
You'd best read the thread again.
It's not my fan.
There is another option w/o replacing the fan-4" to 3" reducer.