Draught from Cooker Extraction Fan

BarneyMc

Registered User
Messages
201
I have a draught coming in from the extraction fan over my cooker. The duct runs outside and simply hangs down from the roof outside.

I would like to block the duct outside but that would mean I would not be able to use the extractor fan. Any ideas on how to stop the draught coming in but be able to use the extractor fan?