Oslo 500 smoking - any ideas?

[bostock]

hey folks wondering if you have any input here: running the oslo all season, no problems with draft. Suddnely draft is BAD, started about a week ago. When i open stove door, smoke rolls out - choosing to roll out of stove rather than draft up. Specs: 6" vent/pipe into 8" SS liner (length of 6" is approx 18"). All vertical. Yes there is a typical draft loss going from 6 to 8 but the chim is approx 25' high and there were no draft problems until just last week. I removed colar and 6" (everything to the liner) and tested with incense - there is some draft up into the liner but not strong - could it be an issue from firebox to collar? I removed the insul blanket, cleaned everything out, didn't make an improvement. I will have chim cleaner come out next week but it's hard to imagine an 8" so full that the draft is that poor (so suddenly).
The wood i burn is a mix - lots of hackberry, locust, oak, most seasoned 18-24 months, some as much as 4-5 years. Any ideas, i would appreciate the help.

 

[Jon1270]

Go outside with binoculars and look to see if the screen on the cap is clogged.

 

[Wood Heat Stoves]

About 95% of the time when someone has symptoms like you describe it's the spark arrestor screen in the chimney cap that's clogged. Creosote condenses on cool surfaces so the smoke ifs probably pretty cool by the time it does from 6" to 8" and up 25'. Other factors that can contribute are damp or poorly seasoned wood-more moisture to condense, and burning the stove at low air settings for extended periods. I have to clean my screen after 2-3 weeks sometimes depending on how I'm burning and my wood. Could also be a down-draft problem, cold air sinking in the chimney, but most likely the screen in the cap (assuming you have one which is required).

 

[firefighterjake]

1) Creosote in the stove pipe, chimney or screen . . . check and clean if needed

2) Down draft if the temp outside is close to the temp inside . . . try to open a nearby window while lighting the fire or reloading

 

[Shari]

Yup - what they said above.

 

[PapaDave]

Agreed.
Have you been burning at a bit lower temps recently due to warmer outdoor temps?
This does sound like the cap is clogging, and once it starts, it can get worse pretty quick, depending on burn habits.

 

[bostock]

i called chim sweep (twice - still no return call)...but i do believe it is clogged cap. Looks clogged when i look with binoculars, anyway. I disconnected at stove - shined flash light up there - can't see any obstructions but i know that may not mean much - but i doubt the entire liner is that full - probably just the cap. No low burns - only typical startup and shutdown). Except the last two burns when i noticed the draft almost depleted to nothing - so no burns now until i get a pro out there. my 32' ladder won't get me where i need to, so i'm waiting for a sweep to come out. I wonder if i should consider a diff chim cap (if that's the prob, anyway - cap getting clogged).

 

[Wood Heat Stoves]

i called chim sweep (twice - still no return call)...but i do believe it is clogged cap. Looks clogged when i look with binoculars, anyway. I disconnected at stove - shined flash light up there - can't see any obstructions but i know that may not mean much - but i doubt the entire liner is that full - probably just the cap. No low burns - only typical startup and shutdown). Except the last two burns when i noticed the draft almost depleted to nothing - so no burns now until i get a pro out there. my 32' ladder won't get me where i need to, so i'm waiting for a sweep to come out. I wonder if i should consider a diff chim cap (if that's the prob, anyway - cap getting clogged).

I can tell when my cap is starting to get plugged by how the stove is acting but I can also see through the screen from my driveway when it's clean. When it's blocked I can't see light through it from the other side. In Cal. a 1/2" mesh is required but may be different where you are. I'm always tempted to take it out but remember a story a guy told me who burnt 1/2 his house down from an ember that landed in his deck. He took his screen out because his neighbor, a fireman, told him to!

 

[Jags]

Depends on local rules (do you need a spark arrestor) and the surrounding area, IMHO. That is a judgement call. I use 1/2" hardware cloth to keep critters out. No plugging after several years of use.

 

[Billybonfire]

What colour smoke is it ?
Black smoke = no Pope
White smoke = new Pope.

Sorry couldn't resist.

 

[PapaDave]

I can tell when my cap is starting to get plugged by how the stove is acting

Ditto.
Time to check and clean when that happens. Mine's easy though, so I tend to do it anytime needed.

 

[xman23]

After cleaning the 1/4 inch screen on my cap, twice in one year, it had to go. That was over 10 years ago. I had a plan to replace it with 1/2 or 3/4 material, but never did. Some here cringe when it is sugested, remove the screen, but others and myself haven't had an issue.

 

[Wood Heat Stoves]

1/4 inch is really small. I can see why you took it out but it should have been at the min 1/2". If you ever decide to try it again use that.

 

[tcassavaugh]

1) Creosote in the stove pipe, chimney or screen . . . check and clean if needed

2) Down draft if the temp outside is close to the temp inside . . . try to open a nearby window while lighting the fire or reloading

i vote on needing a cleaning....if you have been running ok, then it starts backing up its normally in need of running a brush through the system or cleaning the spark arestor.

cass