I have a large fireplace, with a square 12x12 clay lined flue, which I am shopping for a coal insert to install. I have been pondering what happens to the convected heat inside the fireplace (behind the shroud). My current thought is to install a stainless steel liner the full length of the flue. There does not appear to be a requirement that a liner be insulated for coal exhaust, but I would likely wrap the liner anyway.
Convected heat would rise in the flue and be cooled by the clay tiles, drop then reheat and repeat. Options seem to be that I could plug the base of the flue (around the liner) with mineral wool; OR insulate further by pouring in vermiculite / Perlite insulation between the liner and the tiles. These are open ended ponderings (please comment), but I do have a specific question which is...
Inserts have a pseudo outer shell that fans blow room air through to heat the room with. Why not go a step further and insulate (encase) the insert behind the shroud with mineral wool?
... would this cause more of the heat to be transferred to the room?
Coal Insert, Convected Heat Inside Fireplace
- davidmcbeth3
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One should insulate between the shroud and the chimney bricks .. mine has std insulation to create a "seal" .. for the pipe from the stove to the top of the chimney, mine is insulated.
- McGiever
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Here is a worthy Quote I found while SEARCHING...
Photog200 wrote:Another good insulation for this install would be rock wool. It is made from slag and is fire proof to 2000°. You can get this at Home Depot and Lowe's.franco b wrote:A block off plate is nice but all it needs is to stuff fiberglass insulation around the smoke pipe to seal off the damper area. Much easier.
Randy
- Formulabruce
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When you put in your 6 inch flue pipe, it will be sealed around the top of the chimney before the cap. The heat doesnt escape much. It helps keep the chimney warm though, aiding in your drafting at a slower burn. Most people I know use a rock wool on bottom and sealed at the cap..