A while back I needed to take an air tube out of my Regency i2400 insert. I was told to place a wrench on the tube and bang it to the left with a hammer. But this thing didn’t budge. Stove is only a year old. Is there some kind of trick? Do I have to twist it or something first, or was I doing something else wrong? I don’t need to remove it now, just curious for the future if I ever do again. Thanks.