You make some good points, but I don't think that a pellet stove sucks that
much air. That being said, why worry about any outside air connection?
I'll be running a 4 inch exhaust pipe up an 11 inch chimney liner. So why
not draw down outside air around the 4 inch exhaust? Does it make sense? I
guess it depends on the "air tightness" of your home. The manufacturers
stipulate that an outside air connection is absolutely mandatory in a mobile
home installation. My question then is: why not in a non-mobile home? If
you have modern windows (which I am in the process of installing), any home
could be air tight (not just mobile homes). And if you're running the
pellet stove 24 hours a day, it might deplete a significant amount of air if
there's no outside connection. Of course, all houses leak to some degree.
My original question deals with whether not it's advisable to provide an
outside air connection in a home that's not a mobile home.
"Goedjn" wrote in message
...

I'm installing a pellet stove insert in a masonry fireplace that is
located
in the center of my home (no access to an outside wall) and would like to
add a outside air connection. I'm installing the exhaust flue (probably
4")
inside of a 10 inch diameter SS re-lined chimney. Can I terminate the
outside air connection inside of the chimney just above the damper
blockoff
plate, assuming that I run the exhaust flue all the way up the chimney to
the cap (about 15 vertical feet)?

If you suck the outside air down alongside the exhaust pipe,
you'll cool the exhaust pipe. I don't know if that's
an issue with pellet stoves, but it would be with a woodstove.
Also, unless you put some sort of baffle at the top, you risk
sucking the rapidly cooling exhaust gasses back down the
chimney as they exit the exhaust pipe. I can't offhand
think of any terribly awful consequences of that, but it's
probably not the behavior you want.