Attached is a picture of the damper of a QTR140 Broan bath exhaust fan. The view is from inside the housing with the fan motor and squirrel cage removed. With the fan not running, we feel cold air under the fan in cold weather. With the fan not running, the damper is always horizontal as shown in the picture. A Broan tech rep advised us that this can indicate a damper that was installed upside-down. We sent Broan this picture but apparently they did not look at it. If you’re familiar with these fans, can you tell us if this damper is upside-down?
Fred
Lakewood, CO
Replies
Fred,
Nutone, Bosch or Panasonic butterfly dampers should lift when operating and flop down and close when shut off.
Damn the drywaller for leaving the fan on while sanding also.
Calvin, thanks for your reply. Because accessing the damper will be a nasty job, I was hoping someone could confirm from the picture whether the damper was installed upside-down. As installed, the exhaust edge of the round flap bends up. Do you know if that is correct?
Best regards, Fred
Fred,
Exhaust flapper, closed when down and both halves should fly up to allow the fan air to go up and out of the room.
The blowing air opens the flapper to exhaust the air.
I viewed your picture on a phone and they looked open but without a fan operating, that meant to me that something wasn’t kosher in Denmark.
All the gunk on the flapper won’t help.
The flappers are usually a part of the fan housing but they do make inline flapper assemblies. Which type are we seeing?
Thanks.
Calvin, this flapper is a single piece of round plastic. It is inside a plastic housing (damper/duct connector) that the installer must snap into the steel fan housing. Broan sent us the installation instructions but they do not include a picture of the installed flapper. Attached is a picture with the fan removed and a large wire nut being used to hold the flapper closed for the photograph. The instructions say "Attach
damper/duct
connector.
Snap damper /
duct connector
onto housing.
Make sure
connector is flush
with top of housing
and damper flap
falls closed"
I will probably have to go into the attic to see if the connector is flush with the top of the housing. If not, it must be upside-down.
Best,
Fred
Fred
Sorry for any confusion I’ve caused you.
I think you’re on the right track in the attic.
And do report back!