Is the rectangular damper needed if there is an external damper already at end of the exhaust duct outside?
This is a 2-part question. The AHDA1 comes with a damper-assemply (rectangular adapter) or a 7 in round connector (no damper). My question has to do with conditions where there is no damper, or alternatively conditions where you may wind up double-dampered. So will there be problems if I use the included 10 x 3.25 rectangular damper-assembly to connect with the exhaust duct when there is already an external damper outside built into the exhaust end cap? And for those who are connecting using the included 7 in diameter connector (no damper) will they need to add a damper somewhere in the duct-work if none exists?
Thank you for your question. The 3 1/4 damper is required if vent outside. If using 7" round duct work, you can use a 7" round in-line damper along with your outside damper. It is normal to have a damper at the unit and a damper outside. For further assistance, contact Technical Support at 888-336-6151.
Date published: 2018-10-29