Liner question

[adkww]

I have a Jotul F500 wood stove and plan on installing a SS liner into my existing masonry chimney that I built about 7 years ago. It’s a block chimney with a clay liner. Metal pipe exits the stove and goes thru the wall for about 28 in. into the flue tile. From there the run is straight up for 23 ft to the top of the house. Chimney is located on the outside of the house. The existing clay flue liner is 8 x 8 with an actual inside dimension of 6 ¾” x 7”. The sales rep recommended a 5 ½ in liner since the room inside the flue is very limited and if I used a 6” pipe I would probably not be able to get it down the existing clay liner. He also said that since the SS liner has smooth walls and because the run up to the top is a good length, going down to 5 ½ verses 6” would be acceptable and my draft would not suffer at all. Makes sense since I’m going from a square clay to a round metal flue. My draft has always been excellent. I have tried contacting Jotul about this but have had no luck. I also will be adding insulation but since a wrap blanket will not fit, I plan on using the vermiculite/cement mix the company sells for this very reason by filling in the space between the SS liner and clay liner. Anyone out there have any thoughts on all this?

 

[bholler]

I would break out the old liners and put in the 6" with enough insulation there is abosolutly nothing wrong with pour in but for it to be properly insulated you need 1" of insulation that you will never get with your current setup

 

[adkww]

I would break out the old liners and put in the 6" with enough insulation there is abosolutly nothing wrong with pour in but for it to be properly insulated you need 1" of insulation that you will never get with your current setup

I though about taking out the current liner but it is a long way to the bottom and the liner is pretty secure inside. Seems like I would have a heck of time breaking it up and taking it out, that is why I leaned toward leaving it in. Any easy ways to remove it?

 

[pma1123]

I have the same situation as the OP, but on a 7x7 inner dimension tile flue in a vacation home that sees less than a cord per year. What is the downside of not having insulation around the liner? Higher chances of creosote buildup? Can you install the liner and try it without insulation to see how it works and add pour-in insulation later? I understand its not optimal.

 

[bholler]

I have the same situation as the OP, but on a 7x7 inner dimension tile flue in a vacation home that sees less than a cord per year. What is the downside of not having insulation around the liner? Higher chances of creosote buildup? Can you install the liner and try it without insulation to see how it works and add pour-in insulation later? I understand its not optimal.

Yes you can do that but it will not have adequate insulation to meet the zero clearance to combustibles requirement Which means to be to code you would need to have for an exterior chimney a 1" gap between the outside of the masonry to any combustible material.
http://www.rumford.com/code/clearances.html

Any easy ways to remove it?

Yes there are several tool we use to break them up and shovel them out the bottom but it is not really a diy job