I'm redoing the pipe from the stove to the snout inside the thimble. Doing this to increase my distance from the masonry wall. I read that the male end should go into the stove back. This to allow and liquid to drain back into the appliance. I can't seem to get the 6" pipe to go into the stove to allow this process. I can get the pipe to go over the stove back exhaust port. Am I missing something? I'm trying to use Ventis black 22 gauge welded seem pipe.