Flue Liner Installation

[Hedley]

This has probably been anwered on the forum somewhere but I can't seem to find it.

I am contemplating installing a Jotul Rockland 550 insert into an existing woodburning fireplace. I will have it professionally installed. The existing fireplace is a steel heatilator type measuring 36" x 24" x 24". There is a fresh air vent to the front of the firebox. When installing the stainless steel flue liner (which will run to the top of the existing masonary chimney) should the opening through the existing damper be sealed off around the liner. And should the top of the liner be insulated to prevent air returning down around the liner. The installer I am talking to suggests that this remain open to prevent the liner from overheating.

 

[Wood Heat Stoves]

seal it up, high liner temps= clean safe chimney etc

search the question :to insulate or not?:

 

[begreen]

The liner is going to be handling high temp gases for it's entire lifetime. It is made to be hot. You actually want the flue gases to stay hot all the way to the top in order to prevent creosote condensation. If this is an exterior chimney, I would consider installing an insulated liner for best performance, especially if the chimney is old or short.

 

[Hedley]

The installer that I have been talking to is suggesting a flexible liner. Am I correct in assuming that flexible flues are uninsulated. If so can you recommend a brand that would be insulated. Does the damper sealing plate that is shown in the Jotul installation manual come with the unit or is it an extra and part of the chimney installation?

 

[begreen]

With flex liner, the insulation is either wrapped around the pipe or it is poured in after the liner is installed. A damper block off plate is an option for masonry chimneys. It's shown in the manual on page 10 for a stubbed in installation for when the liner does not go all the way to the top of the chimney.

"A sealed block-off plate must be installed at the
damper area of the existing fireplace, unless the
liner is connected to the top of the chimney. See
fig. 8."