Bitter wood aftersmell. Exhaust fan installed helps but sucks cold out

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dizwiz21

New Member
Feb 6, 2018
3
Northeast ohio
Hello, greetings.

This is my first post to this forum.

Help me with wood odor...

I have a 16x20 ft great room with a big opening fireplace in the center of one of the 20 ft wall. Cathedral maybe 12 ft tops. Chimney is about 15 ft tall total.

Previous owner admitted the fireplace flue is not wide enough for the fireplace opening size. Its looks to be a fairly standard square cross section liner. Perhaps maybe 12” by 12” or whatever size is common.
He installed a smoke guard to cut down on the fireplace opening.

Had it swept when we first moved in 2013, has got 3.5 solid seasons of use on it (fires 1x a week for 12 weeks in winter).

Installed, at high expense, a fan on the top to force a draft out.

Its always a fine line adjusting the rotary dial between Too much airflow - and suck all heat out. Or too little and get an odor.

Fans are not a perfect solution.

I have another fireplace in my office. It drafts amazing. The fireplace opening is smaller, and the chimney is way higher. Prob 20 feet tall. There is never any issue with smell there. But to be honest, i rarely ever use that fireplace. It has a similar 12” square cross section clay liner all the way up the chimney. I also had it swept in 2013.

The smell from main fireplace can stick around a while even after sweeping out all the ashes. A few weeks.

I use split, seasoned logs from my own property. I couldnt tell you what kind of trees they are.

Ill admit when i first moved in, i was dumb about splitting and seasoning, sometimes using wood recently cut and not split enough. I dont do that anymore.

At one time i noticed a creosote build up so i sprayed creosote cleaner and built a hot fire. It turnes any shiny black creosote into flakes that crumbled.

I am simply wondering what else i need to do to avoid wood odors inside.

Is it the type of wood im burning that smells bad?

Is the creosote lingering in my chimney making it smell? (Its hard for me to imagine drafts pushing the odor past a closed danoer into my home, but i guess anything is possible)?

Do i need to have a brick mason extend my chimney taller to ensure perfect drafting?
We did have a power outage once, stopping the chimney fan and making house stink. Lol

I dont mind spending the money to fix it. I love the look and feel of a real wood fireplace (my wife wishes we had gas. Lol).
 
Last edited by a moderator:
I measured my fireplace opening sizes:
Great room (16x20 ft room)...40” tall with smoke guard x 48” wide
With 16 ft tall chimney


Office fireplace. 26” tall, 30” wide
With 20 ft tall chimney

Both look to have the same square cross section flue clay chimney liner appr. 12” by 12”
 
So a rough rule of thumb is that the ratio of fireplace face opening to chimney flue area should be no more than 10:1 By your measure, the Great Room fireplace to chimney ratio is 13.3:1. That is likely to cause the fireplace to emit smoke into the room under some conditions. That's probably why a fan was suggested and installed. You may want to consult with a chimney sweep or mason familiar with fireplace construction about possibly rebuilding the fireplace to make its face area smaller so that it will fall within the 10:1 ratio. Or better yet, install a wood stove, and insulated flue liner and actually get good usable heat from burning wood. Modern wood stoves with glass in their doors can be even more mesmerizing than a fiireplace fire.
 
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Made think about a insert with 6" stainless steal liner for the great room?
 
One other concern with a flue fan. What happens if you have a nice e fire burning in the fireplace and there is a power outage?
 
One other concern with a flue fan. What happens if you have a nice e fire burning in the fireplace and there is a power outage?

Room fills with smoke, you throw a bucket of water on the fire, and the house warms up for the first time in a month because that huge hole in the roof is finally not pushing out so much air?
 
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