Insulation at fireplace damper

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oldoak

Member
Jun 18, 2014
9
Roanoke, Va
I recently had propane logs installed in a masonry fireplace and have question about insulation. This masonry fireplace is in a finished basement and I have not used it for a couple of years, but last time we used it burning wood. Since that time, I had a piece of R30 unfaced insulation pushed up toward the damper lid as it was slightly warped. When the installer came I had forgotten about the insulation and they removed it during the installation of the logs.
My question is if I can put the insulation back up to the damper? Would the propane logs get hot enough to melt the installation if ran a few hours? I don't know how much hot/cool air escaped through the unleveled damper lid but it made me feel better thinking I was closing an air gap in the house. The house isn't air tight as it was built in 1973 with 2x4 walls and brick veneer, but has new doors/windows. My second idea was to remove the cap off the flue and install the installation at the top of the chimney then reinstall the cap but didn't know how the moisture/rain would fair to the insulation being exposed.

Thanks.
 
You need to have the damper at least PARTIALLY open when burning your gas log set.
The manufacturers include a Damper Clip to keep the damper from closing., which is installed when the logs are
put in. Don't put insulation back in the flue. You need to have Carbon Monoxide evacuated from your home.
If you block it in, you may wake up dead.
 
Thanks DAKSY for your recommendation. The log set stated it can be operated as either vent free or vented, but did not include any damper clip. The manufacture states the flames will be higher using it as vented, but the damper lid doesn't sit flush and has gaps around it already. Since this log set is not being used daily nor as main heat source I was concerned about keeping energy loss to a minimum.