Extending chimney test

[Ctwoodtick]

so I would like to try to extend the liner/ chimney on my Jotul rockland insert. I have about a foot or 2 short of the minimum 15 feet of liner required. The stove functions fine ( to me at least) but often get smoke out of the door when I open it up. Before I pay to have brick chimney and ss liner extended, I wanted to make sure adding length will work. I’m guessing the way to test this is to get adaptor to fit into top of existing liner and attach temporary stove pipe that matches size of existing liner. If that fixes issue
, then go ahead and do it good and proper as a permanent thing. What I have now on top of brick chimney is a double flue cap, for reference. Am I correct with this being how to test this?

 

[begreen]

Depending on the setup and safe access to the chimney, you might be able to get a 3' length of 6" warm air duct pipe from a big box or hardware store. It should be crimped on one end. Remove the liner cap and insert the crimped end into the liner. Don't force it. If it won't fit then the end of the temporary pipe may need to be crimped again. Do this on a calm day. Then test the insert and see if there is a notable difference.

 

[Ctwoodtick]

Depending on the setup and safe access to the chimney, you might be able to get a 3' length of warm air duct pipe from a big box or hardware store. It should be crimped on one end. Remove the liner cap and insert the crimped end into the liner. Don't force it. If it won't fit then the end of the temporary pipe may need to be crimped again. Do this on a calm day. Then test the insert and see if there is a notable difference.

Thanks for the reply, if the 3’ addition does not do it, would you just keeping adding length until in did?

 

[EatenByLimestone]

I'd suspect the addition will help. We're still fairly warm, so you may not see a big change until it gets down to the low 30s, high 20s.

 

[jetsam]

I used a piece of 26g galvanized HVAC duct from home depot as a test. Helped me noticeably on warm days.

 

[begreen]

Thanks for the reply, if the 3’ addition does not do it, would you just keeping adding length until in did?

You could pick up a 2' and a 3' length and try one or both if necessary. Pretty often a few feet can make a nice difference.

 

[fire_man]

I addded 2.5 feet to my 18' chimney and it made a huge difference for the Woodstock Progress.