Re: How long is to long for a Dryer vent?
The 90 degree transition adds an equivelant of 5 feet of restriction in the ducting.
When you add 7 feet plus 5 feet ( the 90 degree ) plus 7 feet = 19 feet.
However ... I would suspect there is also a 90 degree elbow coming from the back of the dryer so ... 5 + 7 + 5 + 7 = 24 feet. which should be fine without any additional fan needed.
Besides ... I wouldn't put any type of fan inside the dryer duct since it will add restriction and will get covered in lint which may cause this fan to overheat.
Hope this helps.
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