Hello.. I just purchased a new to me pellet stove and I’m planning my install. I’m planning on switching my old wood stove to a pellet stove, England stove, and I just had one question. I’m reusing a chimney flu which I will line with 4in liner. My stove “requires” an OAK but my run of the 2” pipe would be 12’. Is it okay to have a run that long? I can only find 10’ lengths, I’m planning on using a piece of exhaust pipe as a union to extend that. Also is there any required clearance of the intake pipe (combustibles) ? My code book doesn’t mention it at all. Thanks!