I've had this Enviro Windsor pellet stove for a number of years now and now I want to connect it to the outside to take in combustion air. My problem is that the tube that comes out of the back of the stove seems to go nowhere! It's just a metal tube that goes into the back of the stove and doesn't make any connection to anything. It just terminates into a vented heat shield. I looked through the book and I can't find an answer.

Any ideas? Jim