Connect each duct to a "Y" connector, then secure it to the inline fan. A single 6-in. duct runs from the fan to the vent hood through the roof. Some inline fans have plugs and others are hard-wired.

Step 6: Air Tight The Muffler Seal the insulation ... And once done, connect the exhaust of the inline fan with the duct. If it still seems tough to deal with noisy inline fans, you can try ...