kitchen exhaust fan
I redid my kitchen in Oct. 2007 (a total gut, remodel). My exhaust hood is over a cooktop and vents to the outside by going down behind the wall into the crawl space and then about 15 feet to vent to the outside. It turns out that for the past year and a half the grease has been collecting on the fan blades and there is nothing in the collection cups. What could be causing this? Could it be caused by the outside vent being blocked by leaves?
Thanks for any help/advice.