On Dec 18, 9:33 am, John McGaw wrote:
shederr wrote:
On Dec 17, 1:10 pm, John McGaw wrote:
shederr wrote:
We recently moved into a home (built in 1982) and it has a wood
burning fireplace. We love having a wood burning fireplace, but
we've recently noticed the hearth gets very cold and there's quite a
draft coming from the fireplace. We've read and been told to close
the flu and hold a tissue in the fireplace to see if it moves
(indicating a draft through the flu). We've done that and the tissue
does not move. We've used fireplace caulking around the fireplace
between it and the brick surround.
The draft seems to be coming from the vents underneath the fireplace
(sorry, not sure what that's called). It's as if the area around the
fireplace itself is letting a draft in. We want to continue using the
fireplace and hate to block these vents, but we've covered them with
towels for now while it's not being used. Is there a way to remove
this vent covering and insulate underneath there or is there something
we should do at the top of the chimney that will solve this?
Replacing the insert is a bit costly for us right now. Is there
anything else we can do to cut down the draft from under the
fireplace?
Thanks in advance for your help!
I'm having a hard time figuring out what you might mean by "vents
underneath the fireplace". Three possibilities I can see are 1) an ash
pit 2) air vents from outside which provide makeup air to the fire and
3) some sort of heat circulation arrangement but these probably aren't
all the possibilities.

What sort of firebox does your fireplace have (steel, masonry?). Where
are these vents located relative to where the logs rest on the grate or
andirons? Are there other vents than the ones you mention (like above
the firebox opening)? Is this fireplace a pre-fabricated unit that was
inserted into an opening in the wall with bricks added for decoration?

--
John McGaw
[Knoxville, TN, USA]http://johnmcgaw.com

The firebox is steel. I don't have a picture, but found a couple
through MSN images that are close to mine.
The urls a
http://www.royalhomes.com/options/im...-Fireplace.jpg
and
http://www.fireplacesnow.com/gif%20files/11bgd48n.jpg
Hopefully you can get to these url's.

Anyway, the vents that seem to be drafty are below the box area where
you place the logs. There are also vents just inside the doors on
both sides. They each have a chain coming through them with a pull
that says "pull to close". I'm not sure what those are supposed to be
closing. There are also vents at the top above the box but there is
no draft from there.

The unit is not set into (flush with) the wall, it sticks out from the
wall.

If the doors are airtight, or nearly so, then the side vents inside the
doors may be for makeup air for combustion. It seems a good chance that
the vents above and below the firebox are connected and are for
extracting heat from the metal enclosure (in at the bottom and out at
the top when the metal enclosure is hot) to heat the room. I'd certainly
close the side vents when there is no fire, just in case they are part
of the problem.

You can probably get closer to figuring out what paths the draft is
taking if you can obtain a "smoke pen". This item can probably be found
at a well-equipped hardware store although I haven't actually looked for
one myself. It might just be that the firebox is cold enough that air is
naturally entering the upper vents, going behind the firebox, and then
falling out the bottom vents. Of course it could also be that there is a
humongous hole back there somewhere leading to the outdoors. Does
anything show outside the house near the fireplace -- like a screened
air intake?

--
John McGaw
[Knoxville, TN, USA]http://johnmcgaw.com

John,
I'll take a look at it tonight and see if there is a screened air
intake outside the house. What if there is?