Lost my draft

So for no apparent reason I lost the draft on my stove tonight. This chimney has always had good draft. It had an oil fired water heater that used to be hooked to it and would pull a draft no problem at humid 100 degree outside air temps with a barometric damper besides.

Today’s conditions was 53 degrees outside. Stove was idled down with 110 degree stack temps and 220 stove temp. Ash pan vents open about a pencil tip worth (hardly at all). We were out putting up the Christmas lights. Wife goes in and comes back out says the house smells like a stale fart. I walk in and knew right away what it was. Walked downstairs and the Mano was at 0. Opened the basement door and ash pan door. Draft instantly jumped to -.04 Left the ash door open for about 30 seconds and closed. Left basement air out while I serviced the stove and brought coal in. Everything settled back in about -.015. Nothing was running in the house at the time to cause a vacuum. The proceeded to turn on bathroom fan and power vented water heater. Draft held -.012. I have no idea what cause that chimney to stall out with a live fire. Although slight, this chimney historically has draft even when nothing is hooked up (will Draw dust into itself). I have an 8’ long stove pipe run on a 45 degree angle as seen in the pics, hooked to an 8x8 masonry chimney approx 22 feet tall. The digital reading was taken with the water heater still running.

Here is the correct picture

Lack of make up air is my guess.

Above 45 degrees and I have to crack a window to maintain a draft.

B, sometimes weird, unexplainable things just happen--believe me, I know with mine!! LOL Tomorrow she'll be fine. Don't panic--YET! Try crackin ash door vents a tad more.

Cracked a window and cracked the ash door vents to about 1/3 of a full circle. The co monitor started to register but I caught it in time and ventilated before they went off. The part that bothers me is if we weren’t home and this happened it could have killed my dog. He’s afraid of smoke alarms (and they say Rottweilers are fearless) His hiding spot is in the basement by the coal stove.... The only other time this happened to me was when the stove was on the much bigger 12X12 chimney and it was 80 degrees outside in the middle of February so I was anticipating it and caught it instantly

That elbow didn't possibly get nudged further back in the thimble!!!!!!!!!!!!!!!!!!!!!!!! That's a long run--everything is clear? No birds, etc. gotten in chimney??

About as clean as it gets. I replaced all the stove pipe this year and lit it up with charcoal. Stove has only been burning since Monday so clean as a whistle. F good suggestion on the 90 in the thimble but also good. This setup was the same last year and all was good. Even when we had heat waves in the middle of winter and hit 70 degrees. It could be that my dumb ass didn’t have a window cracked which I think I did all last winter but can’t remember

Also I have a cap on the chimney and sent the brush down it 6 weeks ago for good measure to knock the dust down then vacuumed out the chimney crock

Give that window a shot & hopefully she'll be good. Not to worry, both my 100 lb. dogs have their own hidin spots when I test CO alarms--puppy is just realizing he don't fit under the bed any more!!! LOL

The good Lord was watching over us last night. Got up at 245 to take a leak and thought something didn’t seem right. Bedroom CO detector was reading 61 and hallway detector was reading 67. Opened the whole place up and was clear in about 45 min. The whole time I was doing this the stove HAD draft. -.014 as read on my digital and confirmed by the Dwyer. I went around the pipe joint connections with a lighter and found two spots where the flame would draw in so I put some furnace cement in those places. I’m at a loss for how CO got out while under a draft unless the draft stalled or reversed before I woke up and was corrected by the time I saw it. Going on the roof today to look down the chimney and probably going to pull the chimney elbow even though the stove is running so that should be a good time...

Sounds like a good plan B. Be careful!! Gotta be somethin goin on there. Check back in the bi-metallic flap.

How old is the stovepipe? The only time I had that smell with my handfed was when I ended up having pin holes in my pipe.

Good point N--those are sometimes real hard to see.

If you have a clean out door for the chimney it might not be sealed tight.