coals, cold chimney and smoke

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Jotul118

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Dec 4, 2013
83
Western Massachusetts
Okay, so here's the situation. If the chimney is cold and there are not many ambers left in the coals do I want to move the coals to the back of the firebox and start a new fire?

I know normally you rake the coals forward to restart the fire, but when I went to do it they actually kicked out a good amount of smoke.

The Carbon Monoxide alarm went off early this morning. This has happened twice. I haven't fully filled the box for a full overnight, so when I come down to check things out, I go to restart the fire and get smoked out.

Do I push coals back and pre-prime flue?

Do I put some paper balled up behind coal pile?

When Carbon Monoxide detector goes off do I just want to totally close down damper and air vent?

I'm taking it that when it's cold, the draft from the cold chimney is carrying the CO2 via: the improper combusting coals into the space.

My girlfriend is a very light sleeper and has to commute each morning and she is at the end of her rope with being startled awake. Then when she is startled awake she rants and raves (brings me to the end of my rope) while I'm trying to get the fire going again to burn off everything. Listening to her while dealing with the plumes of smoke is a recipe for some Jekyll Hyde action. lol

I'm rambling at this point but would love some words of wisdom.

By the way, there is plenty of draft and the chimney height is ample. The chimney is triple lined but does still get cold creating the cold down draft.
 
Somewhat strange scenario as you have some heat in there so it should be hotter than the rest of the house creating draft so there must be a draft issue in the system.

- Try checking the chimney for blockage and run a brush through it
- Open the air all the way for 5-10 minutes before opening the door to get what coals you have left heated back up
- gently open the door and gently move the coals to a pile (front/back/either side/spread around) depending on your needs. The reason we all suggest the front is the incoming air helps them ignite the new load.

If you have decent draft and are patient this should get the flow going in the right direction. If it doesn't I would guess there are other issues?? If no other issues can be discovered then repeat step 2 and after 5-10min throw in a couple balls of news paper to get the flue heated.

These are just my best guess without seeing pics or knowing more.

May be a prevailing wind issue combined with chimney height and roof line etc.. Not enough heat to overcome a steady down draft. In which case adding more chimney may be in order. Take some pics of your set up - inside and out and post them.
 
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What type of flue do you have - internal, external, masonry, lined, insulated etc? How tall is the flue and what type of house ( basement install, two storey home etc)

My guess is your flute has gone cold and there is no draft or draft reversal. In that case, all the standard tips apply - open a window, newspaper fire to restart flue, make sure exhaust fans are off.

In my last house, we had a basement install with a short external steel flue. It would often smoke the room out if I didn't tee prime the flue when re kindling a fire.
 
Thanks for the suggestions as thus far. I'm headed up into the hills to take down a few trees for next season, but when I get back down I'll take some photos of my set up.
 
If possible open up the primary air for a few minutes before you open the door, charcoal burns very clean if given enough air.
It was around 3 am. that I got up and I believe I may have opened up the damper but kept the air intake mostly shut, which I am thinking maybe squelched an already tired bed of coals. I'm thinking that perhaps the coolness of the stack temperature combined with the tired bed of coals is was created the improper combustion that would have spilled the CO2 into the living space?

I'm thinking if I had just left the damper nearly closed as well as the air inlet, there would not have been an issue?

Bear with me because, this is my first set-up with an exterior stainless chimney system.

I'll take photos of my set-up in the morning and post them. I was also high up on a ladder today pruning out some spruce tree branches that are around the structure which may have also been stifling the most efficient flow of air possible.

So much to learn and so fun to learn, but not in the moments like early this am..
 
What type of flue do you have - internal, external, masonry, lined, insulated etc? How tall is the flue and what type of house ( basement install, two storey home etc)

My guess is your flute has gone cold and there is no draft or draft reversal. In that case, all the standard tips apply - open a window, newspaper fire to restart flue, make sure exhaust fans are off.

In my last house, we had a basement install with a short external steel flue. It would often smoke the room out if I didn't tee prime the flue when re kindling a fire.

I'll get more of that info to you in the morning, but it is an exterior, stand alone, triple wall, stainless steel Duravent chimney system. There is one 2 foot section of single wall pipe running from the back of the stove flue into a 9 inch section of Duravent that runs through the wall as part of the T that feeds into the stove pipe. There is 15 feet of chimney and I believe I am within the 10 foot distance they talk of away from the roof. The ceiling is pretty low and being that the space is pretty small and I was able to, I went straight into the wall from the back of the stove and 90 degrees straight up. There are no twists or turns, just straight through the wall and up.

The stove seems to pull a great draft and it just roars along and I definitely need to make use of both the air inlet control in unison with the damper to keep its temperatures where they need to be.

I'm thinking by being half awake at the time and pushing the coal bed back while keeping the air inlet almost fully closed yet opening up the damper all the way, that I created a situation where the coldness of the piping won out over the draft and the fuel being pushed in the back of the stove? I think had I left it alone (damper 3/4 closed and air inlet a finger tips worth open), that it would have just slowly extinguished?
 
Why do you have the air inlet mostly closed when you're starting a fire? Maybe I'm misunderstanding you because that makes no sense to me. Most people not only have the primary air all the way open but crack the door a bit to get a new fire going.
 
Why do you have the air inlet mostly closed when you're starting a fire? Maybe I'm misunderstanding you because that makes no sense to me. Most people not only have the primary air all the way open but crack the door a bit to get a new fire going.[/quote

Yes, you misunderstood or I need to back to school for how I try to describe things. lol

I only dial down the air inlet and damper when I turn in for the evening for a longer burn time.
 
OK, my bad. Glad to know I'm not trying to talk to a crazy person.==c

Can't help you with your draft/smoke/tight house problem, I'm afraid. My 200-yo house breathes very nicely, so I have no experience with any of that more complicated set-up.

I am, however, entirely incapable of reloading a stove competently in the middle of the night, so it could be your guess on that score is the right one. Personally, I wouldn't even be able to remember in the morning what it was I'd done in that state of fog.
 
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Here are the photos of my stove and chimney set-up. Left a window cracked downstairs last night which seemed to help along with my also filling the box with more wood. Someone had brought up the length of flue section which is interesting, because as you can see in the photo, it is not only on the shorter side but also single wall to help with more radiant heat. I didn't think about its being single wall effecting things. I read up a little bit on negative pressure and stack effect. I have had a window cracked open upstairs for fresh air, but I'm taking it, that that can draw draft away from the stove. It made sense to me in reading that structures are, indeed, a chimney of sorts.
P1050797.JPG P1050798.JPG P1050799.JPG
 
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Here are the photos of my stove and chimney set-up. Left a window cracked downstairs last night which seemed to help along with my also filling the box with more wood. Someone had brought up the length of flue section which is interesting, because as you can see in the photo, it is not only on the shorter side but also single wall to help with more radiant heat. I didn't think about its being single wall effecting things. I read up a little bit on negative pressure and stack effect. I have had a window cracked open upstairs for fresh air, but I'm taking it, that that can draw draft away from the stove. It made sense to me in reading that structures are, indeed, a chimney of sorts.
View attachment 120433 View attachment 120434 View attachment 120435

Thought I'd share a couple photos of a work in progress.

P1050804.jpg

P1050806.jpg
 
What a pretty stove! Have you looked in the manual for clearances? I'm pretty sure you can put it a lot closer to the wall, which will reduce your horizontal run and help with draft.
 
The straight back section off the stove is part of the problem. Ideally it would have had some up slope before the thimble.

Might be just the picture but it almost looks like it slopes down.
 
Might be just the picture but it almost looks like it slopes down.

Right. It needs 1/4" rise per foot of horizontal according to code. Ours is 1/2" rise per foot and works fine.

I don't think the single wall pipe is a problem so long as you have some rise.
 
Thank you all so much. A friend helped me install it and long story short, there is a bit of a drop rather than the appropriate rise. I thought it may have something to do with things early on, but after thinking about what might be involved to rectify things I kind of put it out of mind for my own sanity at the time.

Any ideas aside from basically taking everything down and carving out more of the wall out to nudge the whole Through The Wall kit up? I'll check my clearances because I like that idea, would that help things a bit more?

How does that slight of a drop effect things? In layman terms please! lol
 
Flue gases travel along a horizontal run of pipe in a different fashion then a vertical run so you need the rise to help the movement of the gases.
 
When I saw the pic what would be involved in getting rise in that pipe was the first thing I thought off. And frankley with that thimble height do not have a clue. That is one of the lowest rear exit height stoves on the planet.

Saying, ya need it but I don't know how you get there from here. Wish to heck you had been here when you were planing that flue installation.
 
Flue gases travel along a horizontal run of pipe in a different fashion then a vertical run so you need the rise to help the movement of the gases.

Question answered like a seasoned teacher! Thank you!
 
When I saw the pic what would be involved in getting rise in that pipe was the first thing I thought off. And frankley with that thimble height do not have a clue. That is one of the lowest rear exit height stoves on the planet.

Saying, ya need it but I don't know how you get there from here. Wish to heck you had been here when you were planing that flue installation.

Me too! I am happy to be here now though!

It's a bit annoying but all in all the stove is working out great. I hope I have the stove for quite a while because I don't want to think about constructing a whole new chimney system. Because of the low ceilings in the space (just under 7 feet), this set-up was great in theory and doesn't take too much away from a small floor plan.

When I was looking online originally I really didn't see any examples of straight horizontal stove pipe runs going into the flue. I noticed the slight downward slope after everything was said and done on the day of installation, but I was too tired and wanted to believe it wasn't a big deal.

Live, Learn and Look Forward as they say!
 
One creative pondering I have sitting in front of the stove at this moment it chiseling down into the marble with a slope, so I can still move the stove up and out to take apart the components for cleaning and as well as resolving at least some of the drop in the small section of stove pipe leading to the flue.

I guess that those with longer stove pipe sections leading to the flue are able to wiggle sections apart to clean between the box and flue? I would love to think there's an easier way to approach mine with the build up adapter from the stove to the stove pipe and then between the damper and flue.
 
A big concern is that CO levels are already way up there before they set off the alarm. Get one with the digital read out that will let you push a button and see the highest reading that didn't set it off.

CO will flat kill ya. Period.
 
Put the front legs of the stove up on a couple of firebricks and see what it does to the angle of the pipe to the thimble. At this point straight into the thimble would be better than what ya got.
 
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