Scary moment tonight when smoke started filling the house...

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Samcanadian

Member
Nov 12, 2019
34
Winnipeg, Canada
So lately we've had some nice weather (finally) and it's been the first three or four days in a row where we haven't had a fire. I even went so far yesterday as to clean out the firebox in the assumption we'd be shut down until fall. Well, I had spent some time outside as the sunset and got a bit of a chill so decided to bring the old boy (the less than one year old Osburn 2000) out of retirement for one more fire.

One thing I think I should mention is that all day today, anytime I would sit in the living room with the stove I would get a very faint whiff of wet wood. Like, as if it had rained on the ashes of an old camp fire. I took my wood-carrying satchel out to the garage because it was covered in soot and I figured that might be the culprit, but I still could smell it and just assumed it could be the fireplace. My other thought was that we had rain last night and I thought that perhaps a little bit of water got down the chimney and all I was smelling was damp ash or something of the like (of course, we had no issue with this all winter, including through heavy snowfalls etc).

Anyway, I lit a fire like I have probably 150 times already and knew something was up immediately as smoke from the lit newspaper didn't immediately begin to draw upwards...in fact, it started to come back into the living room. I shut the door up right away (I usually keep it open a crack for 10 minutes while the fire starts to roar before closing it up) and turned the vent to closed....but smoke still kept billowing through the cleanout at the bottom and through the minimally open front vent. I went to get my fire extinguisher just in case, and basically sat there handcuffed trying to figure out whether to risk opening the box to pull the wood out or else cross my fingers that WHATEVER is plugging up the chimney becomes unplugged. Eventually, enough flame developed and I started to see smoke start tracking up to the roof of the stove and the billowing smoke stopped almost immediately.

We left the doors open for 10-15 minutes and no sooner than it filled, the house was clear of smoke again, and my stove burned happily along as if nothing had happened.

So...any idea what happened? I've never had drawing issues before with this stove, but then again I've never lit a fire in plus temperatures yet. I'm going to let this fire die out and then I'll get the chimney sweep out right away to check the chimney and see what may have happened. I'm wondering if maybe birds took the opportunity to start building a nest on my chimney? We did notice an obscene amount of blue jays, crows etc with grass and twigs in their beaks around our place the last few days...
 
Some stove manuals suggest lighting a single match in the stove first thing you do, to check your draft. I bet you may consider that on warm days!

your draft was reversed initially due to the warmer temps outside, or that plus winds, or could be a few other factors. Smelling the “wet ash” smell is a tip off.
 
Some stove manuals suggest lighting a single match in the stove first thing you do, to check your draft. I bet you may consider that on warm days!

your draft was reversed initially due to the warmer temps outside, or that plus winds, or could be a few other factors.
It was warmer, but still was only 15 degrees C (60 F) at the warmest part of the day. Would that be enough to throw things off?
 
It does seem unlikely that it was the only factor. Any chance there was an exhaust fan running, vent hood, or dryer?
 
It does seem unlikely that it was the only factor. Any chance there was an exhaust fan running, vent hood, or dryer?

There's a chance that my wife had the dryer running, as she's been doing laundry this evening. I haven't had an issue to this point yet with that though when starting fires, but do you suppose that in addition to the slightly warmer temps would be what would make the house fill with smoke like that?
 
Yes, the warmer temps mean a weaker natural draft due to a way lower difference inside to outside. Normally your winter draft pressure was likely overpowering any countering effects. Especially considering the usual winter temps in... Winterpeg!
 
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Yes, the warmer temps mean a weaker natural draft due to a way lower difference inside to outside. Normally your winter draft pressure was likely overpowering any countering effects. Especially considering the usual winter temps in... Winterpeg!
Ok good to know. Would that slight damp, smoky smell be a consistent thing now for us in the summer? It's not overpowering but it's there...and I'm wondering if I should just expect this for the rest of the summer now.
 
Could be. Can be common in summer depending on where your stove is located in the house. Can be remedied to avoid, good idea to do so both for odours as well as potential condensation from the incoming air. Google “stack effect” for interesting info on the issue
 
Ok, sounds like I have a few things I can check on. Sounds like getting a chimney sweep by to do a summer cleaning is first on my list though.
 
You definitely had a downdraft, my solution is to just open a window on the same floor where the stove is to help get the draft going, if its windy open the window on the upwind side of the house.
 
Once you shut down for the season, brush the chimney then put a temp cap or seal on the top for the summer if the smell persists, you might just have one of those houses that has reverse draft when it gets warmer, or more humid / damp outside.
 
We start lots of fires when it’s in the 60s and we have a short stack. Bath fans, hood fans in kitchen, or even dryer can cause this when the loading door is open.

So shut off the fans for a minute, open a door to the outside, and/or shoot your propane torch up the chimney for 30 seconds before turning it in your kindling.

In your case I’m most worried about this happening all summer long and you smelling that stink the whole time. I have a proper outside air connection so no stove or chimney air comes into the home.
 
Classic draft reversal. The odor you detected earlier in the day is a confirmation. It can be exacerbated by many things (eg radon subslab ventilation system, wind, etc), so you don’t necessarily need to have outdoors warmer than indoors to cause it.

Lots of folks block their chimney for the summer, most commonly by stuffing a fist full of insulation into the pipe from below, to prevent smelling the stove all summer. They also make inflatable balloon type products for this purpose, or even top dampers, if you desire. Just make sure to leave yourself a note inside the stove to remove the plug, there’s more than one story of people forgetting and lighting up a plugged stove the following fall, which can create a real mess.
 
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Classic draft reversal. The odor you detected earlier in the day is a confirmation. It can be exacerbated by many things (eg radon subslab ventilation system, wind, etc), so you don’t necessarily need to have outdoors warmer than indoors to cause it.

Lots of folks block their chimney for the summer, most commonly by stuffing a fist full of insulation into the pipe from below, to prevent smelling the stove all summer. They also make inflatable balloon type products for this purpose, or even top dampers, if you desire. Just make sure to leave yourself a note inside the stove to remove the plug, there’s more than one story of people forgetting and lighting up a plugged stove the following fall, which can create a real mess.
Ooof I can imagine lol

So update today: Zero smell. It was another warm day today, but absolutely none of that same wet, fireplace smell as before. We'll see if this lasts. Fingers crossed. If it happens again I'll take your recommendation.
 
Shove a big towel/blanket/pillow whatever, up the flue, to stop the reverse draft. Just, don't forget to remove before your next fire. I have whole house fan that would pull drafts down thru this, and I would actually leave a little string dangling down or something on it, to remind me that's it's there.