Carbon Monoxide after fire goes out

Hi everyone,

I have a Dutchwest Majestic Cat Stove from 1996 and it's been burning great. However, every time the fire dies out, my CO alarms go off in the room. I've tried sealing everything and re-gasketed the entire unit. It's very frustrating and I'm not sure how to prevent it. My chimney is an exterior setup that skirts up the side of the house (pics included) so cold-chimney syndrome might be at play here. I can see the little red embers still glowing inside the stove and I'm afraid the gasses aren't rising up the chimney. Has anyone else experienced this problem or know of a fix? Thanks.

fatjay said:

Is your chimney double wall insulated? Sounds like when the fire gets cool enough, all it takes is a gust of wind to blow the cold air down, the cool air feeds the fire, and blows the byproduct of the burning embers into the house. I get this from time to time, so I try to keep it hot, or shut it down entirely.

Click to expand...

Yes, it's a Selkirk Super-Pro double wall. How can I shut it down entirely?

Another instance is when the house cools down (around 4 in the morning) and the T-stat kicks the heat on, the central air unit sucks air from the center of the house. It's sucking air from the wood stove and spreading the CO all throughout the house. I guess wood stoves and central air units don't mix?

Thanks everybody for all your input!
The stovepipe is cold by the time the CO alarm starts going off, yet there are traces of red embers still left. I now have to make sure the central air handler for the furnace is turned off, both on initial startup of the fire and when the fire starts dying down. Otherwise it'll suck air upstairs from everywhere. The furnace and blower are located in the attic of our bi-level home and the wood stove is downstairs. I have read about negative/positive pressure zones and that very well may be the case. I've done toilet paper tests and it's shown that air is getting sucked into the house through downstairs windows, and pushed outside in upstairs windows. Neutral is between 4ft and 5ft up from the ground on the second floor.
All of our appliances are electric, so I wouldn't think there would be an issue there. I made sure that no blowers throughout the house turn on in the morning, so I don't think they are associated with the CO issue.
Fatjay, I have no vents to close on the chimney. From the stove, the pipe goes up, then a 90 into the wall, into a tee, then up the house. Should there have been some sort of shut-off valve installed?
Kennyp2339, there is no outside air kit for this model stove. The non-cat stove has one, however.
Velvetfoot, I've thought of that, but that's a little over-budget for us at the moment. That probably is the best solution though, before installing a chimney inside the home.

I have noticed when I leave a downstairs window open overnight, the CO alarms don't go off in the morning. The resolution seems to be to provide make-up air downstairs. However, it's freezing in the morning when I leave a window open and completely nullifies the advantages of having the wood stove... HELP!

Mellow, yes it's single wall going into class A through the thimble. I can try switching over to double wall, but I'm afraid to spend the money when I'm not sure that little bit of extra insulation will make a difference. Right when the chimney exits out through the wall, it's completely exposed to the cold air outside, which is where most of the chimney is.

rwhite, I think you're absolutely right. Once the fire dies, the CO starts pouring out the air intakes of the stove due to the cold chimney/negative pressure. Unfortunately, there is no OAK for my model; only the non-cat model. Attached is a basic layout of the home. If the furnace turns on in the morning, the upstairs CO detectors go off around 4-5am, both in the hall way upstairs and the bedrooms. The lower one only goes off if the furnace is off, around 8-9am. We do not load any more wood after 11pm. What happens is the furnace sucks air from the intake in the hallway and dumps heat and CO into the three bedrooms upstairs first along with the living room/kitchen/dining room (because of the proximity of the bedrooms).
Again, thank you everybody thus far.

fbelec, I remember the top being pretty high when I was last up there, but I will take some measurements and verify. Thanks. I found this site and took a photo of it, and describes exactly what I'm experiencing. Last night I had the fire die down overnight and left a window open... No CO alarm. But, it was FREEZING downstairs. It really is a shame that's what I have to do.