Clogged cap

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Oh no, the cap screens can easily be clogged every couple of months even when burning good fuel properly. The time to cloggage has to do with size of the mesh, size of the cap, and yes you can gunk it up with poor burning habits. Many of us had screen cloggage while the rest of the flue was very clean.

I understand, regarding the cap screen. That's why I don't have one; I prefer to just deal with birds in the chimney in springtime. My cap has four vent slots near the top, with no screen. Those entire openings were what I had clogged up, with what looked like a wall of solid creosote. With binoculars, I could see crud build-up that had practically filled up all the holes. The chimney itself was remarkably clean, with very little soot or creosote stuck to the interior wall. The Sooteater appears to have whipped most of the build-up out of the vent slots. Just a trace of visible crud in one of the holes now, and looking up the chimney from the bottom cut-out, I see a lot more daylight. And oh yes, the flue draws better now.

I'm curious what kind of poor burning habits could cause the cap vents to clog up while not depositing a lot of creosote inside the chimney itself.
 
I believe mine was just really damp weather. My chimney was just about spotless, but the wire section of the cap was a solid brick of creosote. Wood burned here is all hardwoods, and at least 4 years C/S/S. We start exclusively with super cedars, and nothing else gets burned in the stove either. I have been tempted to toss in the daily junk mail.. but I don't. LOL
 
My screen also got clogged last year so I just removed it. I burn dry wood and the liner had hardly anything in it, so I think it's just the cold air condensing the smoke on the screen/cap.
 
Burning very dry firewood with 600-700 degree flue temps and I no longer have any problems. A few years ('10-11) back I had to bang the top of the cap with an extra long paint pole to dislodge the built up creosote. Not really much accumulation in pipe after using Sooteater but still some build up on cap. A steep metal roof which only the bravest would traverse for a cleaning. The Sooteater is a real godsend.

The last few years have been relatively clean though.
 
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Is paper and cardboard really that bad in causing creosote? Does the shiny, colorful advertisement part of the paper, vs. the regular newspaper, make a difference? I have been heavily dependent on newspaper.
 
Is paper and cardboard really that bad in causing creosote? Does the shiny, colorful advertisement part of the paper, vs. the regular newspaper, make a difference? I have been heavily dependent on newspaper.
My understanding is that cardboard sends big chunks of burning ash up the chimney that is real good at touching off creosote.
 
I never burn paper or any thing than dry wood. Start the fires with supercedars. Wood has been CSS for two years moisture around 12%. I think the last super cold snap caused it -5' F. Sooteater on order, Snow on roof means I can't get up there to properly clean it.
 
Thanks to the people that suggested a Sooteater. It did the job in fifteen minutes, I cut the nylon an extra inch and the chunks of creosote came flying down.
Now have a perfect fire. THANKS for everything!
 
Good news. I'm glad you're up and running again.
 
When my screen pulgged, it was a gooey mess. The chimney was fine. The cap being cold and marginal wood was the issue. My screen was 1/4 inch. Being it plugged half way through the first season, I took off the screen. I assume it may be a code requirement, but it wasn't going to work for me.
 
Every 2 to 3 years for cleaning the cap is indicative of the problem right there.
Should be done every year as should a sweeping of the entire stack.

The debate over screens has been documented plenty enough on here, and my input is proper burning habits and good dry wood provide no issues with a cap screen.
If a screen is clogging, you're not burning dry enough wood, &/or your burning habits need to be rethought and refined.
Another plus to a screen, aside from the obvious critter control, is if it is clogged, it tells you how poor your wood &/or burning habits are, and could be an indicator that the top few feet of flue might have heavy build up also.
Clean every year here, and aside from first year burning less than dry wood and new to adjusting burning habits, never had a screen issue since in 9 years.

Now if the screen has openings less than 1/2", then you may want to consider replacing with 1/2" holes or larger screen. Smaller stuff can clog much easier.
Easy to blame the screen, and not accept that maybe one is not burning as well as they think they are.
 
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Thanks to the people that suggested a Sooteater. It did the job in fifteen minutes, I cut the nylon an extra inch and the chunks of creosote came flying down.

Confused about this- you cut the nylon an inch shorter than it had been? An inch shorter than it came new? Cut them an inch longer than the flue size?
 
I have a 6" flue so I cut them for a 7" as the cap appears a little wider. The screen is 1/4 inch screen, two years ago we cleaned it I thought of making those larger but figured it would be fine. The top of the stack was in good shape not much creosote only got about a small coffee can out of the whole stack, but with the brush I had the screen could not get cleaned. The chimney has to be accessed from the roof and then climbed so we went to bottom up cleaning. The sooteater actually cleans every thing so we won't ever go on the roof again, except to open the screen to 1/2" opening this spring.
 
Every 2 to 3 years for cleaning the cap is indicative of the problem right there.
Should be done every year as should a sweeping of the entire stack.

The debate over screens has been documented plenty enough on here, and my input is proper burning habits and good dry wood provide no issues with a cap screen.
If a screen is clogging, you're not burning dry enough wood, &/or your burning habits need to be rethought and refined.
Another plus to a screen, aside from the obvious critter control, is if it is clogged, it tells you how poor your wood &/or burning habits are, and could be an indicator that the top few feet of flue might have heavy build up also.
Clean every year here, and aside from first year burning less than dry wood and new to adjusting burning habits, never had a screen issue since in 9 years.

Now if the screen has openings less than 1/2", then you may want to consider replacing with 1/2" holes or larger screen. Smaller stuff can clog much easier.
Easy to blame the screen, and not accept that maybe one is not burning as well as they think they are.

I used to believe this. Until mine clogged. I can very easily look right up my chimney, takes about 1 minute to get the pipe disconnected. Last year when I had sudden draft issues, chimney was very clean, could see bare metal in most of it.. but no light at the top. So I climbed up there and removed the screen, it was solid. I banged it out and replaced it. At the beginning of this season, I swept the chimney, and removed the screen. 26 feet total chimney/flue. It was two years between cleanings, because visual inspection showed it to be clean. We do burn 24/7 in season.

This is the result of that cleaning, less than a cup of soot from two years burning, including the coldest, longest winter in decades... IMHO, my burning practices are good, and so is my wood.

2014cleaning_zpscd48fec0.jpg
 
I'm curious what kind of poor burning habits could cause the cap vents to clog up while not depositing a lot of creosote inside the chimney itself.

You made a leap there. I never said that poor burning habits could cause the vent to clog while leaving a flue clean. I said that poor habits could clog a screen. Good burning habits can also clog a screen but the flue will be clean.

Easy to blame the screen, and not accept that maybe one is not burning as well as they think they are.

Everybody gets an opinion. I have personally witnessed screen cloggage despite clean flues which tells me that the burning habits are not the problem.

Regardless, the sooteater invention sure solves the problem of cleaning these things if you still have one without getting on the roof.
 
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I used to believe this. Until mine clogged. I can very easily look right up my chimney, takes about 1 minute to get the pipe disconnected. Last year when I had sudden draft issues, chimney was very clean, could see bare metal in most of it.. but no light at the top. So I climbed up there and removed the screen, it was solid. I banged it out and replaced it. At the beginning of this season, I swept the chimney, and removed the screen. 26 feet total chimney/flue. It was two years between cleanings, because visual inspection showed it to be clean. We do burn 24/7 in season.

This is the result of that cleaning, less than a cup of soot from two years burning, including the coldest, longest winter in decades... IMHO, my burning practices are good, and so is my wood.
If you cleaned every year, the cap screen might not have been an issue.
Don't know what & how you burn, and you feel you have good wood and burning practices, so seems you are happy with your habits and outcome.
I don't have clogged screen issues, except as I stated, my first year of burning less than dry wood and green burning habits.
Burning 24/7 here with 27' of liner, have never had a screen issue since, other than the screen eroding after 9 years, so I just replaced it this last fall. And I will admit a couple of those years were not the most optimal wood I have burned, not the worst but not the best I have burnt. Even so, no issues with screen clogging.

I will continue to clean every year, as for me it is easy insurance against any issues that may arise. Between waiting 2 years, and visual inspection appearing clean, something failed, as your screen was clogged. Visual inspections from the ground may not be good enough, who knows. Myself, I will clean and inspect every year, and burn comfortably knowing it is has been cleaned and checked. No surprises there.
Stay warm and enjoy.
 
If you cleaned every year, the cap screen might not have been an issue.
Don't know what & how you burn, and you feel you have good wood and burning practices, so seems you are happy with your habits and outcome.
I don't have clogged screen issues, except as I stated, my first year of burning less than dry wood and green burning habits.
Burning 24/7 here with 27' of liner, have never had a screen issue since, other than the screen eroding after 9 years, so I just replaced it this last fall. And I will admit a couple of those years were not the most optimal wood I have burned, not the worst but not the best I have burnt. Even so, no issues with screen clogging.

I will continue to clean every year, as for me it is easy insurance against any issues that may arise. Between waiting 2 years, and visual inspection appearing clean, something failed, as your screen was clogged. Visual inspections from the ground may not be good enough, who knows. Myself, I will clean and inspect every year, and burn comfortably knowing it is has been cleaned and checked. No surprises there.
Stay warm and enjoy.

LOL.. OK.
 
The only bird I have ever had in mine is chimney swifts. They fly down into the chimney, but the interior wall of the stainless steel tube is too slick for them to hold onto, so they slide all the way down to the bottom. Their only exit is through the stove. I keep the damper open so they don't leave a mess inside the AB and damage the very fragile combustion package, plus this allows them to exit the stove pipe into the fire box, as they see daylight coming through the glass door.
Chimney swifts can fly straight up the chimney are you sure they were swifts?
 
The screen is 1/4 inch screen, two years ago we cleaned it I thought of making those larger but figured it would be fine.
I think 1/4" screen is to small we always use 3/4" expanded metal screen and usually our customers don't have issues with clogging as long as they are burning right. But it can still happen if the conditions are just right to cause it
 
I think 1/4" screen is to small we always use 3/4" expanded metal screen and usually our customers don't have issues with clogging as long as they are burning right. But it can still happen if the conditions are just right to cause it

I believe the optional OEM Simpson cap screen was a 1/2" wire mesh, not diamond expanded steel but like a wire screen. Hard to remember and it has long been trashed. It's a filter so the more porous the filter, the longer it should last.
 
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