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ron ll
12-24-2012, 01:20 PM
I'm old enough to have used fireplaces a lot in the past, but alas it was in the past. We have a nice very seldom used fireplace in the living room that had glass doors on it. It has always drawn well and been fairly smoke free even with the glass doors open. But thru a recent remodel, the doors were taken off to be replaced in the near future. But I built a couple of fires recently and it drew well.

So Saturday night K. had a bunch of her girlfriends over for dinner. I built a small fire and watched it for a while. It was drawing beautifully so I left to meet the guys for a nip. An hour later I get a panic call from K. saying the fireplace was blowing massive amounts of smoke into the room. From my stool at the bar, I hadn't noticed that a brisk wind had come up. By the time I got home, she was right, it was a massive amount of smoke. The fire was out and the doors were open. The damper was still open.

So my question is what went wrong? Obviously fireplaces like this have been used for centuries without glass doors. There has never been a cap on the flue, but again surely many old fireplaces worked without them.

So we'll put new glass doors on it, but I doubt I'll ever light that thing off again.

Paul Girouard
12-24-2012, 01:32 PM
#1: Did you tighten up the envelope during the remodel?

#2: Did you add any new exhaust fans? Bath, kitchen hood, etc?

#3: Did you check the flue for obstructions, (more than likely not the issue if the fire you lite drew well before you left the house)?

My guess is a combination of #1 and #2.

Paul Pless
12-24-2012, 01:36 PM
architects. . .<sigh>

Mrleft8
12-24-2012, 02:56 PM
Doors to the house being opened created a reverse draft.
A poorly designed flue almost requires doors to draft properly. What is needed is a good smoke shelf which forces the heated air in the chimney forward in the flue preventing cold outside air from entering the combustion chamber through the chimney. If doors to your house were opened it was easier for the fire to feed it's self from the chimney, and vent out through the doors.

ron ll
12-24-2012, 02:58 PM
So anyone have any good cures for smoke smell?

Mrleft8
12-24-2012, 03:02 PM
So anyone have any good cures for smoke smell?

Bake cookies.

bob winter
12-24-2012, 03:03 PM
Live with it. Don't ask how I know.

One problem may have been the size of the fire. A larger fire will create a better updraft than a small one will. When I do burn the damned fireplace, which seems to be maybe once every two years, I make sure the fire is good and healthy.

Paul Pless
12-24-2012, 03:05 PM
So anyone have any good cures for smoke smell?Cook some collards and big honking batch of chitlins. :d

George Jung
12-24-2012, 03:07 PM
I'd consider putting a sealed insert in - either wood, or gas.

ron ll
12-24-2012, 03:30 PM
architects. . .<sigh>

Hey. I didn't design this thing. If I had, it would have worked. :)

Paul Pless
12-24-2012, 03:35 PM
Hey. I didn't design this thing. If I had, it would have worked. :)It happens in our home too sometimes. We have a really tight stove that burns very hot with a tall stainless steel lined chimney in our bedroom. I also have a large wood burning stove with a very tall stainless flue in my garage. If those two are kicking its a bad idea to attempt to start a fire in the fireplace in our den as the other two will pull that fireplace in reverse.

Ron Williamson
12-24-2012, 03:40 PM
Too small of a fire that went out before wood got burned up and the draft got going.
I agree with George.
Get a chimney liner too.
R

Chip-skiff
12-24-2012, 03:45 PM
Lay down some newspapers or an old tarp in the fireplace and see if you can see daylight. If not, shine a flashlight up the flue and look for obstructions. In a seldom used chimney, there can be resin and ash crusts that have flaked off the inside, bird or mouse nests, dead birds, etc. You can poke around with a long, flexible rod (bamboo, junker fishing rod, etc.) but don't look up as you do so, or you might get a faceful. Creosote in the eyes will put you out of temper. Another tactic is to find old chain and dangle it down the chimney. Before doing it, tape an extra-large trash bag or sheeting over the fireplace to keep the ash from flying all over the room.

(You can buy flexible rods and chimney brushes at most hardware stores and do a proper job. Or get a local chimneysweep to clean it each fall.)

When I was a volunteer fireman, we used to get called out on Christmas day to put out chimney fires. Folks would stuff those seldom-used fireplaces and stoves with Christmas wrap and boxes, and set off the accumulated resin in the chimney or stovepipe. Good way to burn down your house.

Steve McMahon
12-24-2012, 03:48 PM
Lay down some newspapers or an old tarp in the fireplace and see if you can see daylight. If not, shine a flashlight up the flue and look for obstructions. In a seldom used chimney, there can be resin and ash crusts that have flaked off the inside, bird or mouse nests, dead birds, etc. You can poke around with a long, flexible rod (bamboo, junker fishing rod, etc.) but don't look up as you do so, or you might get a faceful. Creosote in the eyes will put you out of temper. Another tactic is to find old chain and dangle it down the chimney. Before doing it, tape an extra-large trash bag or sheeting over the fireplace to keep the ash from flying all over the room.

(You can buy flexible rods and chimney brushes at most hardware stores and do a proper job. Or get a local chimneysweep to clean it each fall.)

When I was a volunteer fireman, we used to get called out on Christmas day to put out chimney fires. Folks would stuff those seldom-used fireplaces and stoves with Christmas wrap and boxes, and set off the accumulated resin in the chimney or stovepipe. Good way to burn down your house.

yes yes yes.

ron ll
12-24-2012, 03:54 PM
Okay, as I get more info it is starting to add up. K. now tells me that she was busy in the kitchen and evidently one of her guests put another log in after the fire had died. So there was no updraft left. That coupled with some wind gusts that blew the smoke in. Then opening the doors exacerbated the problem as some of you have pointed out. Probably a better course of action would have been to light a sheet of newspaper and hold it up to the flue to restart the updraft, and leave the doors close. So now the expensive new remodel has lost that new car smell.

Peerie Maa
12-24-2012, 03:54 PM
Lay down some newspapers or an old tarp in the fireplace and see if you can see daylight. If not, shine a flashlight up the flue and look for obstructions. In a seldom used chimney, there can be resin and ash crusts that have flaked off the inside, bird or mouse nests, dead birds, etc. You can poke around with a long, flexible rod (bamboo, junker fishing rod, etc.) but don't look up as you do so, or you might get a faceful. Creosote in the eyes will put you out of temper. Another tactic is to find old chain and dangle it down the chimney. Before doing it, tape an extra-large trash bag or sheeting over the fireplace to keep the ash from flying all over the room.

(You can buy flexible rods and chimney brushes at most hardware stores and do a proper job. Or get a local chimneysweep to clean it each fall.)

When I was a volunteer fireman, we used to get called out on Christmas day to put out chimney fires. Folks would stuff those seldom-used fireplaces and stoves with Christmas wrap and boxes, and set off the accumulated resin in the chimney or stovepipe. Good way to burn down your house.

Can you get to the roof? Lower a brick down on a rope, then tie a small bush to the top end. After covering the hearth pull the bush down with the rope. Make absolutely sure that the sheet covering the fireplace is secure.

May be the small fire could not compete with all of the cold air being drawn in from the room. With the doors refitted on the fireplace the only air in the chimney will be hot and so will draw better.

Peter Malcolm Jardine
12-24-2012, 04:01 PM
Lay down some newspapers or an old tarp in the fireplace and see if you can see daylight. If not, shine a flashlight up the flue and look for obstructions. In a seldom used chimney, there can be resin and ash crusts that have flaked off the inside, bird or mouse nests, dead birds, etc. You can poke around with a long, flexible rod (bamboo, junker fishing rod, etc.) but don't look up as you do so, or you might get a faceful. Creosote in the eyes will put you out of temper. Another tactic is to find old chain and dangle it down the chimney. Before doing it, tape an extra-large trash bag or sheeting over the fireplace to keep the ash from flying all over the room.

(You can buy flexible rods and chimney brushes at most hardware stores and do a proper job. Or get a local chimneysweep to clean it each fall.)

When I was a volunteer fireman, we used to get called out on Christmas day to put out chimney fires. Folks would stuff those seldom-used fireplaces and stoves with Christmas wrap and boxes, and set off the accumulated resin in the chimney or stovepipe. Good way to burn down your house.

+1.

ron ll
12-24-2012, 04:02 PM
Can you get to the roof? Lower a brick down on a rope, then tie a small bush to the top end. After covering the hearth pull the bush down with the rope. Make absolutely sure that the sheet covering the fireplace is secure.

May be the small fire could not compete with all of the cold air being drawn in from the room. With the doors refitted on the fireplace the only air in the chimney will be hot and so will draw better.

Yes, I agree, if we intend to ever use it again, we need to have the chimney cleaned and lined. It is very difficult to access the top of the chimney. It is in the middle of the roof and the roofing is, believe it or not, aluminum shingles. I had never seen aluminum shingles before we bought this house. But they work great as long as they are not disturbed. But you can't walk on them or they simply bend. Plus it's an 8/12 pitch so it would be tricky even if they didn't bend. It's going to require some kind of snorkel lift and even that is problematic because there is no place close to the house to park it. Maybe next xmas I might just put a picture of a fire in the fireplace.

George Jung
12-24-2012, 04:04 PM
Ooooh, put a large-screen LCD set in there, run a 'fireplace loop', and yer in bizness!

ron ll
12-24-2012, 04:09 PM
Ooooh, put a large-screen LCD set in there, run a 'fireplace loop', and yer in bizness!

You might be onto something. It might be just the place for the TV she won't let me have in the living room anymore since the remodel. I'd much rather watch the Seahawks whip the Forty Niner's butt than a fire anyway.

Mrleft8
12-24-2012, 04:46 PM
A well designed fireplace/chimney reflects radiant heat into the room w/o sucking all the warm air out. You may see residual light from the top of the chimney on the firebox floor, but you shouldn't be able to see the sky up the flue..... That's the kind of chimney that sucks the heat out of a room.

ron ll
12-24-2012, 05:32 PM
you're not kiddin'. The fireplace in my daughter's den is a beautiful field-stone thing... but it is completely unusable. The reason: the chimney barely clears the den's roofline, which is one story lower than the main roof of the house... so it is impossible to develop a draft of any kind, no matter how much we pre-heat the flue. From what I'm told, the chimney would have to be raised another 10 feet, at least, for the fireplace to actually work as intended.

You should have chosen a better architect. :)

JayInOz
12-24-2012, 05:34 PM
Ron to access a steep roof here I tie a strong rope to the top of a long ladder, throw the rope over the roof, slide the ladder up until the rope tie is just past the ridge line , then tie off on the other side. You'll need a second ladder to get up to the first, but you'll be able to climb on your roof without damaging anything.
Most people around here (farm country) still have wood fires- we have two plus the wood stove. One cause of smoke entering the room can be poor design combined with a low barometer, but a most common cause seems to be a chimney that's poorly positioned/ built and most commonly a chimney that's too short- turbulence and a particular wind direction can cause problems.
On a farm I owned many years ago I had unlimited firewood from clearing many acres of heavy timber, but a lot of it was forks, stumps etc. I built a three bedroom timber cottage, and built the stone fireplace eight feet wide, almost six feet high and four feet deep. Anything I could physically skull drag through the door would fit on the fire, including stumps that burned for three days :) JayInOz

Chip-skiff
12-24-2012, 08:22 PM
A well designed fireplace/chimney reflects radiant heat into the room w/o sucking all the warm air out. You may see residual light from the top of the chimney on the firebox floor, but you shouldn't be able to see the sky up the flue..... That's the kind of chimney that sucks the heat out of a room.

With the drapes shut in the room and lights off, you can usually see daylight (I didn't say the sky.) If you can't see any light, then there's probably a blockage. Very often, there will be resin crusts, etc. and the first fire of the fall will crack them off. Our tenant just had a chimney fire with the pellet-stove insert we installed.

I recall fondly having to climb up on a snowy steel roof in bunker gear to stand there running a hose with a chimney-fire nozzle down a redhot flue. My feet froze and my face got steamed and smoked. Made me feel merry and bright.

Gib Etheridge
12-24-2012, 09:55 PM
Two things....

I've built a few Rumford fireplaces. The format formulas work perfectly every time so long as you use a damper that slopes forward when opened. In Rumford's time they didn't use dampers. Cold air falls down the back face of the flue, the cross sectional area of which should be close to square and a minimum of 1/10th the cross sectional area of the open face of the firebox. The cold air bounces off of the smoke shelf and moves to the front of the flue where it combines with the smoke and hot air and rises to the top of the chimney, which should be at least 3 feet higher than anything within 10 feet of it. I've repointed some old stone chimneys that were square in cross section and so big that I could climb up from the fireplace to the top and work my way down chipping out the old lime mortar and replacing it with the more modern mortar. Some of them had compartments built into the side walls to smoke hams and such.

Your house was inhabited by K. and "a bunch of girlfriends". She was in the kitchen, so I expect the range hood was running. Usuallywomen use the bathroom more often than men, so there's a good chance the bathroom exhaust fan(s) were on. All of those fans probably created a vacuum in the house, which is probably pretty tight. The air had to come from somewhere and the chimney was wide open. I've seen less than optimally designed fireplaces that would smoke if only one exhaust fan was running. The cure is to open a window. The fireplace/chimney may not be designed optimally as well.

Here's a good illustration comparing modern with Rumford designs. It won't let me copy and paste the picture, but here it is with the text, which is short and worth reading, especially if one is planning to build a fireplace.

http://www.rumford.com/training/design.html

This book tells you everything you need to know to build the best fireplace possible.

http://www.abebooks.com/servlet/BookDetailsPL?bi=9223270604&searchurl=an%3DVrest%2BOrton%26sts%3Dt%26tn%3DThe% 2Bforgotten%2Bart%2Bof%2Bbuilding%2Ba%2Bgood%2Bfir eplace.

Gib Etheridge
12-24-2012, 09:59 PM
Ron to access a steep roof here I tie a strong rope to the top of a long ladder, throw the rope over the roof, slide the ladder up until the rope tie is just past the ridge line , then tie off on the other side. You'll need a second ladder to get up to the first, but you'll be able to climb on your roof without damaging anything.
Most people around here (farm country) still have wood fires- we have two plus the wood stove. One cause of smoke entering the room can be poor design combined with a low barometer, but a most common cause seems to be a chimney that's poorly positioned/ built and most commonly a chimney that's too short- turbulence and a particular wind direction can cause problems.
On a farm I owned many years ago I had unlimited firewood from clearing many acres of heavy timber, but a lot of it was forks, stumps etc. I built a three bedroom timber cottage, and built the stone fireplace eight feet wide, almost six feet high and four feet deep. Anything I could physically skull drag through the door would fit on the fire, including stumps that burned for three days :) JayInOz

Don't tie off to a car unless you remove the coil wire, or lock the doors and put all of the keys in your pocket. :eek::p

ron ll
12-24-2012, 11:15 PM
We've just decided to accept it as the smokey Christmas. I got her some Smokehouse Almonds and she got me a bottle of Talisker single malt scotch. :D

JayInOz
12-25-2012, 02:30 AM
Hahaha! That's the spirit:) JayInOz