How do I size up a coal burning fireplace with no damper for a Chimney Balloon plug?

How do I size up a coal burning fireplace with no damper for a Chimney Balloon plug?

Q: Jason, We have a coal-burning fireplace that we will never use. The chimney has a smoke shelf and (as far as I can tell) no damper. The chimney measures 14 X 16 just above the smoke shelf. I guess that means we will need to order a custom Chimney Balloon. How much would that cost and how do we go about doing it? – ST

A: ST, Just to be on the safe side I would go with a 15”X18” custom Chimney Balloon.

FYI, If your smoke shelf is far up your chimney you can also measure the space below the smoke shelf and before the damper if that allows enough space for the Chimney Balloon. The most important thing is to look for the most convenient space to reach. If the best location is higher than 12 inches past where you can touch with your hand, consider purchasing an HEK Extender with your Chimney Balloon. – Jason

How to air seal a small coal burner fireplace with cast iron insert?

How to air seal a small coal burner fireplace with cast iron insert?

Air seal a small coal burner fireplace

Q: I have an old coal fireplace, with a cast iron insert. The chimney itself has no damper but the insert does have a narrow flap that I suppose is used as a damper (though a very inefficient one when it the fireplace is not in use). I had to slide the insert out to see what the chimney looks like from the inside, as there was no way to see through the damper slot (which measure about 20″x2″).

The highest and narrowest part of the chimney is 9″x9″. Then it looks like it’s relatively straight/slightly sloping at about 9″x15″. And then slopes again over about 20″ to it’s the largest point of 9″x20″, just above that damper slot in the insert.

From what I’ve read, you don’t recommend positioning the Chimney Balloon on the slope. I’m almost positive I wouldn’t be able to get the Chimney Balloon up to the 9×9 spot (certainly not without removing the insert every time, which I want to avoid).

So, a bunch of questions:
1. What’s the likelihood of me being able to maneuver the Chimney Balloon through the damper slot in the insert?
2. What’s my best position?
3. Related to #2, what’s my best sizing?

4. Oh, and I think the 9″ is really more like 9.25… how exactly are you Chimney Balloon sizes?
Thanks for your help! – ZE

A: Dear ZE, We spoke on the phone briefly about how your coal inserts slide into the fireplace.  Considering there is significant clearance between the top of the insert and the 9×9 fireplace flue area, you will find the 9×15 area to be the best location to install the Chimney Balloon. I understand the walls of this area taper upward on two sides and are vertical on two sides in this area. The Chimney Balloon will grab and hold firm on the two parallel and vertical walls, and it will seal the two slanted walls as well.

Once in place, it is possible to uninstall the Chimney Balloon through the very small 2″ damper opening, but honestly, it is not easy to do. You will have to reach the Chimney Balloon through the damper so you can open the air valve. Once the air valve is open you will have to give the Chimney Balloon 5 minutes or more to release its air. Then you slowly and carefully thread it down through the damper little by little. Fortunately, a 9×15 is a relatively small Chimney Balloon, so there is not a lot of Chimney Balloon material.

If I can be of further assistance to you in this coal fireplace insert application please let me know. – Jason