7in square chimney, 3 or 4in req. ?

[ridgeracing]

I have a 20-22 foot high 7in square mason block chimney that I used for 5yrs with coal stove. Looking to install pellet stove, would there be any problems using this chimney, I usually do get a very good draft

 

[JRemington]

By rights you should go with a 4 inch pellet pipe and a 4 inch liner. But I think if you run a 4 inch pellet pipe and go into it with a 7 to 4 adapter it will work. If the draft isn't good you aren't out anything because you would need the pipe with the liner regardless. Be sure to clean the chimney first.

 

[ridgeracing]

By rights you should go with a 4 inch pellet pipe and a 4 inch liner. But I think if you run a 4 inch pellet pipe and go into it with a 7 to 4 adapter it will work. If the draft isn't good you aren't out anything because you would need the pipe with the liner regardless. Be sure to clean the chimney first.

Thanks

 

[batchman]

Sounds like a similar chimney to mine, except I swapped out a wood stove for pellet due to bad draft. Actually, it worked fine if you opened the outside door .

Mine flue is "far back" in the chimney so I ran 18" of flex pipe in then turned up. Cut it so I could pull it out to clean, think I have an install thread here with pics. All the professionals thought I was nuts but it seemed to me physics should still apply and the building inspector didn't seem to require full liner; so I tried it. All good and the chimney even stays clean.

May you have similar luck with yours,
- Jeff