Hi all, need a little wisdom from anyone who has installed duraplus triple wall pipe to a square support box. My question is.... should my twist lock pipe lock ,and then not spin anymore ,or is it designed to freely spin after being locked together at the support box connection to prevent over-torqueing??? I have two 36" sections attached to a support box,the pipe to pipe locks and doesnt spin anymore,however the pipe to box connection spins but is locked together(wont pull off).looking up the liner all connections look tight and uniform. Is this normal or is it going to pop off on my first burn and torch my house? THANKS,and GOD BLESS!