is it unsafe to run a kitchen fan duct beyond a certain treshold length because, the longer they are, they more grease fumes cool on their way out and collect on the walls, posing a grease fire hazard ?
the ideal would be to situate a stove and its fan right against an outside wall so the duct has a short way out. but that is not the case in my basement kitchen, which is in the middle of the apartment, and it is a city row house, i.e. the other side of the wall is the neighbor's house.
currently, i would have to run the duct about 10 ft, that is the shortest distance between the stove and the outside. is that too long to be safe ? should i consider a fan that just filters and recirculates inside ?