How to clean / sweep double wall pipe?

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GrumpyDad

Minister of Fire
Feb 23, 2022
1,232
Champion, PA
What would be the best method and schedule to clean my setup?

I have 6" double wall stove pipe, that rises up about 8' from the stove before hitting a 45 degree elbow, then another about 4' run before hitting another 45 degree elbow, that connects directly to a ceiling support box. There is a 5' class A stainless chimney pipe with cap.

Im worried about being too aggressive and misaligning my pipe as it was a PITA to get that plumb, and Im also concerned with elbows I complicated my cleaning cycles exponentially.

What are the best brushes/wands to use? Would I get a 6" round brush for 6" pipe?

Also do people use any sort of creosote logs (what if you have a cat installed?)

For my fireplace:
I currently only sweep my chimney for my fireplace about once every 2-3 years. I do see some shiny stuff in there but it's so thin and plastered to the walls, there is just no way of getting that out with the brush that matches the hole. I get MAYBE 2 cups of fine dust falling down after sweeping. It really seems like I'm not doing anything honestly.
 
The stovepipe should have 3 screws, 120º apart, at each joint. That will keep it very rigid. FWIW, our stove has a 45 offset in double-wall stovepipe, and the Sooteater snakes right through it without issue.
 
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The stovepipe should have 3 screws, 120º apart, at each joint. That will keep it very rigid. FWIW, our stove has a 45 offset in double-wall stovepipe, and the Sooteater snakes right through it without issue.
OH I actually have that! I used it one year. A piece of mortar came down and I stopped using it in my fireplace. Doest that make a horrible noise to use? Did you trim the leads so they werent too large?
Also how often do you sweep? Every 2 cords? 3? 5? I know it varies from person to person. Im burning all wood that is under 20% MC.
 
I use a sooteater and I feel like it does a good job. My chimney is straight up so I have no experience going through elbows myself, but I've read on here from several people that this should not be a problem. The sooteater rods do bend quite easily to make the turn
 
I have a nearly identical setup, double wall with two 45's and some length between them, into nearly 30 feet of smooth wall liner. I just use a soot-eater on a corded drill, had to buy two kits to get enough rod (cheaper than extension rods, and you get a spare head).

There's a measurement guide on p.1 of the manual, that shows you the trim length for the whips, for your stovepipe size. I replace the whips after each two sweepings, which is every year for me, as I have two stoves. Rather than buying overpriced whip material from Sooteater, I just bought 1000 feet of the correct string trimmer line from Amazon.

Yes, it will make a heck of a racket going up and down, but no damage done. They make a white rod version now, which is more flexible and designed for stovepipe, but I believe I bought mine back before they had that.

Do note that the sooteater rod joints are not 100% reliable, I have them come apart several times per year, where I have to make a very tight bend in the bypass damper area, no matter how securely they're fastened together. I have nightmares about them coming apart farther up the pipe, where retrieving them would be a major core, but it seems it's only the tight bend at the bypass door that makes them pop apart.
 
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I have a nearly identical setup, double wall with two 45's and some length between them, into nearly 30 feet of smooth wall liner. I just use a soot-eater on a corded drill, had to buy two kits to get enough rod (cheaper than extension rods, and you get a spare head).

There's a measurement guide on p.1 of the manual, that shows you the trim length for the whips, for your stovepipe size. I replace the whips after each two sweepings, which is every year for me, as I have two stoves. Rather than buying overpriced whip material from Sooteater, I just bought 1000 feet of the correct string trimmer line from Amazon.

Yes, it will make a heck of a racket going up and down, but no damage done. They make a white rod version now, which is more flexible and designed for stovepipe, but I believe I bought mine back before they had that.

Do note that the joints are not 100% reliable, I have them come apart several times per year, where I have to make a very tight bend in the bypass damper area, no matter how securely they're fastened together. I have nightmares about them coming apart farther up the pipe, where retrieving them would be a major core, but it seems it's only the tight bend at the bypass door that makes them pop apart.
Yea that would worry me as well. The rods coming apart. I believe I had that concern as well looking at how they assemble. As you are working from the bottom up, there is no pull string to retrieve, requiring disassembly of the stove pipe.

Glad to hear that's what people are using. I will have to look at the manual for how to trim for my smaller stove pipe.
 
The Sooteater head leads should be trimmed to a bit larger than the stovepipe ID. If that is not done it probably will make a huge racket. I run it at a lower speed on my drill and don't find it too noisy. Frequency of cleaning varies a lot with the wood, flue system exposure, stove technology, and how the stove is run. There are too many variables to recommend a set frequency. For a new stove owner, once for every cord burned is a good starting guideline, but someone burning poorly seasoned wood may need to clean every 2-3 weeks. For people burning known dry wood in a secondary tube stove usually once a year is sufficient. Someone burning in a pure cat stove, always on low, venting to a cold exterior chimney may need to do it twice a season. We have been burning long enough with the same species of wood and with good flue temp monitoring to know that as long as the wood is dry, once every other year is sufficient.
 
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Two 45's and snaking around a key damper increases the noise, begreen. It's also relatively quiet on my other stove, with the straight pipe.

I also probably run it faster than you, by your description. I feel it does a better job of cleaning when I run it a little faster, but that's just anecdotal based on what I see coming down the pipe, I haven't set up any real experiment to prove that slower doesn't work. I have it on a corded 3/8" variable speed drill, running around 50% RPM, but I don't remember max RPM on that drill motor. I don't go full motor RPM, because then it whips around a lot, to the point where I'd be concerned about damaging the liner.
 
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Ah, thanks for the heads up. I didn't have a key damper the last time I swept, but I put one in last season so that I could test the effects on the stove and burn. It's not necessary on our 20' flue system, so I did it more for the educational benefit. I'll listen for the added noise.
 
Next time you have your drill in hand, do me a favor and note the RPM on it. I'll try to check mine, next time I'm out in the shop. Although I'm just guessing at "50% throttle", it would be good to see how our speeds compare.

Someday soon I'm going to want to pull the pipe off the bottom of this liner and get a good visual on how it's been holding up the last several years, and if it's beat up at all, we might assume my cleaning practice is to blame for that.
 
My Makita 1/2 cordless drill has a 3 speed transmission. I run it in the low range which I think is 300 rpm at full throttle and I run it maybe at 50% of that? The new ones all seem to have 2 speed transmissions @500 rpm on low. What gauge line trimmer string did you get for your Sooteater head?
 
You made me go check my spools. :cool: It's the .105" Maxi-Edge from Arnold, available in 90 ft. spools for $7 on Amazon. I was wrong about it coming off my 1000 foot spool, as the sooteater called for something different than I run in my regular string trimmers.

I'll try to remember to check my drill motor RPM next time I'm in the shop, but I believe it's somewhere around 2500 - 3000 RPM, based on just looking up spec's on similar DeWalt corded drills sold today. I'm sure the trigger response is not linear (power to rpm-squared type thing), but I'd guess there's no way I'd be anywhere near as low as 300 RPM with sufficient torque to keep the thing spinning, on this drill. Whatever RPM I'm using has always felt about right, I just feather the trigger by feel, but now you got me wondering if too fast

Hey @bholler, what's the recommended RPM on your legit pro whip cleaners?
 
I don't know most of the time I run full speed with a 1/2" corded drill. But it depends what your doing. If I an chipping creosote with chains I sometimes run a faster 3/8" drill
 
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I don't know most of the time I run full speed with a 1/2" corded drill. But it depends what your doing. If I an chipping creosote with chains I sometimes run a faster 3/8" drill
Good to know, I am probably being over cautious. Will be cleaning next week. Looks like colder weather and rain are finally going to show up around the 21st.

Question for Sooteater owners. After how many cleanings should the rods be replaced?
 
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I have the old black rods, which I believe used to be the only model, but are now listed for fireplaces only. They're apparently less flexible than the white rods they make for stoves now, and I bend the hell out of them to get up thru the bypass door and into my flue. Between that, using them on two stoves, and one of them being 30 feet tall, it's likely I'm going to be the first to learn their fail point.

I bought them in 2013, so I probably have about 22 uses on them now, using them twice (x2 stoves) in each of the first two years, and once (x2 stoves) each year thereafter. The joints never popped apart until about two years ago (16th use), and this year I must have had them pop apart at least four or five times.

So, I'd say the joints are failing before the rods themselves, or else I'm just getting less careful with them each year. ;lol
 
During the heavy cleaning season I typically break atleast one 1/2" rod a week. I have only broken a couple of the 5/8" rods in 5 or 6 years and none of the 3/4". The ends on the sooteater rods are definitely where they saved money
 
To the OP: a piece of mortar falling down in the fireplace flue is a concern imo. You don't want any cracks/thinner places where heat can get through.

I use white rods and I have a 90 degree elbow after the pipe goes thru the (concrete) wall into the chimney outside. I don't think stove pipe and class A will be damaged by the soot eater. A (flexible, thinner wall?) liner I'd be a bit more concerned about. But many people use this, and I have not heard of any tearing up a liner.

Do not cut the whips too short - it kills effectivity of the soot eater.

You should not use creosote logs in a cat stove (or so BK tells me).

Finally, when you start burning, and you don't know how your system will behave (with the wood you have), sweep twice a season or every cord (whichever is more often). That'll tell you whether you are doing good. If it's going well (not much, and not shiny), you can slowly decrease the frequency of sweeping. But, I'd say you should only conclude it's safe to do so after two sweepings that are "good", and knowing for certain that the wood you're burning then is at least as good (dry) as the stuff you burned in those first two sweeping cycles.
 
I do a mid year cleaning more for piece of mind than necessity. As for the rods (white rods) and whip, with only twice a year use mine are still in original condition after 4 years.
 
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With my sooteater I run my cordless drill wide open in first gear. Just checked my drill, that corresponds to 550RPM
 
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To the OP: a piece of mortar falling down in the fireplace flue is a concern imo. You don't want any cracks/thinner places where heat can get through.

I use white rods and I have a 90 degree elbow after the pipe goes thru the (concrete) wall into the chimney outside. I don't think stove pipe and class A will be damaged by the soot eater. A (flexible, thinner wall?) liner I'd be a bit more concerned about. But many people use this, and I have not heard of any tearing up a liner.

Do not cut the whips too short - it kills effectivity of the soot eater.

You should not use creosote logs in a cat stove (or so BK tells me).

Finally, when you start burning, and you don't know how your system will behave (with the wood you have), sweep twice a season or every cord (whichever is more often). That'll tell you whether you are doing good. If it's going well (not much, and not shiny), you can slowly decrease the frequency of sweeping. But, I'd say you should only conclude it's safe to do so after two sweepings that are "good", and knowing for certain that the wood you're burning then is at least as good (dry) as the stuff you burned in those first two sweeping cycles.
Well it was sloppy mortar pieces around terracota square pipe that fell, so call it excess mortar. But I didnt want to risk having anymore damage.
 
Yes, but often such pieces rip out mortar from between the seams between the tiles. (Sorry, don't know the right English word for this.)
 
Yes, but often such pieces rip out mortar from between the seams between the tiles. (Sorry, don't know the right English word for this.)
You got it: mortar joints. You could argue whether it's technically bedding vs. pointing, it's really the same thing in a flue tile scenario.
 
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