How do I seal my damper?

[atcomo]

My woodstove is vented into the fireplace chimney. The flex pipe
runs thru the damper. How do I seal the damper where the
flex pipe enter thru it. Do I use insulation? What should I do?

 

[Fsappo]

If it was me, I would use a heavy piece of sheetmetal with rock wool on top and rock wool used to seal off any gaps

 

[Fsappo]

Oh, Shirley, Long Island. I was an East Patchogue guy for about 10 years. Howdy ex neighbor

 

[CarbonNeutral]

Pictures of my block-off plate later in the slideshow (1:01). I have rockwool stuffed above it as well. It's tapconned into the mortar in the firebricks as best as possible, along with high temp silicone around the edges.

 

[CarbonNeutral]

Plus, there are lots of threads - search for damper block off plate