How to use a chimney plug in my chimney, if my fireplace flue has 4 slanted walls? Does a Chimney Balloon really work in this fireplace, or should I make a DIY chimney plug?

Q:  I am trying to use a chimney plug to seal an 11 inch diameter circle damper situation with the rod handle, as you can see in the picture. My goal is to primarily seal the flue from insects and pests and second reason is energy efficiency.
Would you please let me know how to use a chimney plug in my chimney, and which chimney plug and size is best for my damper handle situation. Thanks! – Ibrahim

A: Hi Ibrahim, I would recommend you use the 12″ round Flueblocker above the flue damper. That will work better than a Chimney Balloon in this fireplace. In order to install it, you will tuck the wool pad past the open damper without the handle attached. Then spear the Flueblocker handle into the wool pad clamp and tighten the handle by turning it to thread it into the hole on the clamp. One it is threaded you can use the leverage of the Flueblocker handle to push the wool pad into place above the chimney damper. It will look like the photo below. It will do a great job stopping bugs and drafts. – Jason R

Flueblocker installed in round chimney

Flueblocker installed above the damper

Contact us if you are wondering how to use a inflatable chimney plug or wool fireplace plug as a chimney draught stopper in my chimney?