This is a no brainer I realize - in terms of my lack thereof anyway. I have been tuning my EKO 60, and for the last week or so, it has been "cooking with gas" as they say. Really nice blue flame, and lots of heat. Today, with the snowstorm we got in the NE, I have barely been able to get the thing to run, much less put out great heat. Dull is about the only word to describe its performance. If I hadn't had the chimney apart last week and found it perfectly clean, I would suspect a blockage. Then it dawned on me the wind was coming in from the NE, over the top of the ridge of the house, so that my wife was complaining of smoke smell. Normally all I get is water vapor out the chimney. In warmer weather, and once in a while on other occasions, I have had the same lazy fire problem. So it finally dawned on me the chimney must be the source of these off and on problems. The 8" metalbestos chimney runs through the house, but extends only about 5' above the roof. It is on the western side of the building, only about 1/3 of the way up the roof. With the normal westerly winds, it is fine, but with the wind shift tonight, it just won't burn, despite a beautiful deep bed of coals. I can barely get a fire out of the nozzles. I know the chimney is supposed to be 10' from the roof on a horizontal - I'll guess mine is only about 6', as that was as much pipe as I had, and I figured it should be good enough. Tomorrow I will find someone who sells the pipe and add another 3' on, and my guess is it will solve these intermittent weak fire issues, that I used to attribute to the boiler and the various settings. I guess this is just a reminder of how important the correct chimney design can be to a wood burner.
Suspect Chimney Height Causing Erratic Poor Burning
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I have come across this one time with my EKO where I could not burn right and nothing worked for me, also serious smoke backup issues, my solution was easy as pie I had reinstalled the chimney plug (cleanout at the bottom of the tee outside) incorrectly, and got a puff it blew my plug right out and it sat at the bottom of the chimney on the ground yeah I felt dumb but very relieved the fix was so easy, Good luck boilerman..Dave
Your chimney could very well be to high. If your getting smoke blown back down the chimney it sounds to me like your to high not to short. The rule of thumb that I use when building a chimney ( I'm a part time mason) is for every 3 feet from the roof peak your chimney is you can be 1 foot below the peak. In other words if your chimney were 3 feet from the peak you should be even with the peak. If you were 6 feet away from the peak you could be a foot below, and so on and so on. I would take a section off and try that first.
Is there a cap on the chimney? Caps do more than keep rain out (and excessive corrosion too)! I don't know the regulations in your area but some municipalities require chimneys to exceed roof peak height by no less than one foot. If shortening is what is needed then make sure there is a cap to prevent down draft pressure from overpowering your chimney draft.
GKG-MO please, if your going to be a part time or full time anything: A) learn the codes 10'-2'-3' and B) don't give advise until you know the codes C) if you really are doing things the way you've portrayed, please stop working on building housing anything alive.
Just to clarify on 10'-2'-3'. The chimney must extend a minimum of 3' above the roof. On a flat roof if you meet this requirement you are fine. On a pitched roof the chimney must extend above the roof 2' within a 10' radius from where the chimney penetrates the roof in addition to also meeting the 3' minimum. On a steep roof that can mean a subsatntial amount of chimney pipe extending up from the penetration, more than 5' and the manufacture I used requires a roof guy(a strap that attaches from the chimney to the roof, not a person who works on roofs). I do believe these code requirements are good because it helps ensure the chimney won't be effected as much by wind currents caused by the roof as wind passes over the roof.
clarkharms and others,
Thanks for the input. Actually, my chimney installation is becoming an issue. Both my wife and daughter really complained yesterday of the smells and smoke buildup in the house, and as I said, I could barely keep a fire going. This is from a unit that was burning perfectly the day before. So it has to be the chimney. I have the EKO shudown, and I am going to fix it today, but I want to make sure I get it right.
It is an 8" Selkirk metalbestos. The structure is a converted 100+ year old 35X75 barn, so it is a steep pitch. The barn runs N-S, and the chimney is on the west side, penetrating the roof about a 1/3 of the way up from the eves. It runs through heated structure for about 18 feet, so there is about 6 ft of chimney above the roof penetration. It has the Selkirk chimney cap. The EKO is in the heated basement, connected by about 6 ft of 8" black stovepipe with two elbows. Out of the EKO with one 90 deg, the smoke pipe slopes upward, then connects to the metalbestos with another elbow. I didn't put in a T. Instead, I just remove the smokepipe to inspect and clean monthly or so. So far, there has been no cresote whatsoever anywhere in either the smokepipe or chimney pipe. I have taped up all the joints, so it has a good, leak free unobstructed run, then straight up the metalbestos. I thought I had a good solid installation, and in most weather, it has worked well. However, yesterday with the NE wind apparently coming up and down over the ridge, it really caused everything to back up so that the EKO wouldn't burn properly, and forced very bad smoke and odor into the house. Basically, my wife and daughter won't allow me to start it up again until I fix the problem, so I face a life sentence of going back to fossil fuel if I don't get it right.
I will do the measurements, but to meet the 10' rule, it is going to have to have quite a bit more pipe, probably at least 4', for a total of 10' above the roof penetration. There is no way I can bring it fully above the roof ridge, but I can meet the 10' horizontal rule, I think. I am a worried if I will lose draft, with so much exposed cold pipe. The smoke pipe in the cellar only runs at about 300F when everything is humming. Is there a chance the longer chimney will be counter-productive at some point, and cool the exhaust so much I will actually lose draft and create more problems, with such a cool exhaust temp as the EKO has?
Thanks for the input. Actually, my chimney installation is becoming an issue. Both my wife and daughter really complained yesterday of the smells and smoke buildup in the house, and as I said, I could barely keep a fire going. This is from a unit that was burning perfectly the day before. So it has to be the chimney. I have the EKO shudown, and I am going to fix it today, but I want to make sure I get it right.
It is an 8" Selkirk metalbestos. The structure is a converted 100+ year old 35X75 barn, so it is a steep pitch. The barn runs N-S, and the chimney is on the west side, penetrating the roof about a 1/3 of the way up from the eves. It runs through heated structure for about 18 feet, so there is about 6 ft of chimney above the roof penetration. It has the Selkirk chimney cap. The EKO is in the heated basement, connected by about 6 ft of 8" black stovepipe with two elbows. Out of the EKO with one 90 deg, the smoke pipe slopes upward, then connects to the metalbestos with another elbow. I didn't put in a T. Instead, I just remove the smokepipe to inspect and clean monthly or so. So far, there has been no cresote whatsoever anywhere in either the smokepipe or chimney pipe. I have taped up all the joints, so it has a good, leak free unobstructed run, then straight up the metalbestos. I thought I had a good solid installation, and in most weather, it has worked well. However, yesterday with the NE wind apparently coming up and down over the ridge, it really caused everything to back up so that the EKO wouldn't burn properly, and forced very bad smoke and odor into the house. Basically, my wife and daughter won't allow me to start it up again until I fix the problem, so I face a life sentence of going back to fossil fuel if I don't get it right.
I will do the measurements, but to meet the 10' rule, it is going to have to have quite a bit more pipe, probably at least 4', for a total of 10' above the roof penetration. There is no way I can bring it fully above the roof ridge, but I can meet the 10' horizontal rule, I think. I am a worried if I will lose draft, with so much exposed cold pipe. The smoke pipe in the cellar only runs at about 300F when everything is humming. Is there a chance the longer chimney will be counter-productive at some point, and cool the exhaust so much I will actually lose draft and create more problems, with such a cool exhaust temp as the EKO has?
I don't have enough experience with different installations to definatively tell you won't have any problems but I would doubt an extra 4' would cause you any. The SS insulated chimney pipe on my install remains remarkably cool when running, little over ambient. There is an end point but usually adding chimney height actually helps draft, but causes more initial smoke at the unit until everything heats up. When I installed my woodstock into a 35' length of 6" pipe I had overdraft problems. With the EKO install I have going on I have overdraft problems with my bank account! :bug:
Having a chimney exit low on a steep pitched roof is a tough situation at some wind directions. I don't think more length of good quality insulated pipe will lose significantly more heat. You have a Selkirk cap, is it? I don't think you'll get any better cap. Apart from moving the chimney to exit at or near the ridge (would that be enough project for ya?), adding some more height is about your only option. I know of two similar situations that improved a lot by added something more like 8 or 10 feet. Just make sure you use the aluminum angle brackets screwed deep into the roof framing to beef it up. Selkirk makes hardware to do that.
If you have a good hooded parka, next snow blowing out of the same direction get out (with a flashlight at night) and watch how the wind moves the air over the roof. Might give you a better idea of what's going on.
The smell of smoke in the house might not be only from the stove in the basement. If your house is not very airtight, you might be smelling smoke from outside coming back inside!
If you have a good hooded parka, next snow blowing out of the same direction get out (with a flashlight at night) and watch how the wind moves the air over the roof. Might give you a better idea of what's going on.
The smell of smoke in the house might not be only from the stove in the basement. If your house is not very airtight, you might be smelling smoke from outside coming back inside!
Just wanted to give everyone an update. I added a additional 4' section of chimney today, so it is a total of 30', with 9-10' above the roof penetration. The roof was a mess after the snowstorm yesterday, and there was no way I could get up there to unhook and add another length. So instead, with my weightlifting son helping, I broke the chimney in the attic space above the first floor, and had him lift it up until I could put the 4' piece in, then he lowered it down and we joined everything up just fine. I had to temporarily remove the lock ring, so the joint would pass through the flashing, but I was able to manage to wrap a rope around the chimney on top of the roof and hold on enough to re-install the lock ring.
It really helped - probably 95% better. I think it is 100% fixed, but my wife is convinced she can still smell a little smoke occasionally. We are still getting these darned NE winds. In still air, the vapor plume goes right up and over the roof ridge. When the wind shifts so it comes over the ridge from the NE, the plume is very good - but every once in a while with an odd downdraft, it will want to push towards the eves and the ground. I don't have roof supports on it yet, and won't be able to install them until there is a break in the weather sometime this winter. However, the installation is still rock solid and very strong, so short of a hurricane, I am not too worried about supporting the chimney stack.
The fire is burning much, much better, with nice gasification. I cut the fan speed and shrouds back to where I had them in calmer weather, and it is gasifying perfectly. Somewhere along the line, I will probably try to add another 2' section, but not until I have the weather to put in the roof supports.
Last time I ever install a chimney on the west side of a steep roof. If everyone keeps complaining of the smoke, I may just build a nice spacious furnace room/wood shed off the side of the building where the old milkhouse is now. It is a little too late now though. Personally, I don't smell anything, but then I would probably put liquid wood smoke in my aftershave if they had it, as I think it smells great. However, not everyone has such a refined nose, and once they got smoked out yesterday, it is hard to convince them that the problem is really solved.
It really helped - probably 95% better. I think it is 100% fixed, but my wife is convinced she can still smell a little smoke occasionally. We are still getting these darned NE winds. In still air, the vapor plume goes right up and over the roof ridge. When the wind shifts so it comes over the ridge from the NE, the plume is very good - but every once in a while with an odd downdraft, it will want to push towards the eves and the ground. I don't have roof supports on it yet, and won't be able to install them until there is a break in the weather sometime this winter. However, the installation is still rock solid and very strong, so short of a hurricane, I am not too worried about supporting the chimney stack.
The fire is burning much, much better, with nice gasification. I cut the fan speed and shrouds back to where I had them in calmer weather, and it is gasifying perfectly. Somewhere along the line, I will probably try to add another 2' section, but not until I have the weather to put in the roof supports.
Last time I ever install a chimney on the west side of a steep roof. If everyone keeps complaining of the smoke, I may just build a nice spacious furnace room/wood shed off the side of the building where the old milkhouse is now. It is a little too late now though. Personally, I don't smell anything, but then I would probably put liquid wood smoke in my aftershave if they had it, as I think it smells great. However, not everyone has such a refined nose, and once they got smoked out yesterday, it is hard to convince them that the problem is really solved.
I know NOTHING about EKOs . . . are they anywhere as touchy abought draft as the GW? Have you actually measured the draft?
ISeeDeadBTUs,
I haven't measured the draft, and have no clue as to how I would do it.
I have been studying the vapor plume coming out of the chimney, and I think I just put the chimney in a touchy place. There are tall trees all around, and the structure is a large barn with a fairly steep roof. It seems as though the chimney is in a kind of air pocket. It is doing much, much better with the added height, but with gusts from the wrong direction, it still wants to curl downward, although 95% of the time now, the smoke trails up nicely out of the top. On a clear day or with the normal breeze from the west, there is no problem at all, and I have been burning since Oct with only 2 times where I have had this lazy flame/smoke issue. I don't know if the Eko is more or less sensitive to poor draft instances than any other wood burner. With the blowers and the sealed chambers, I am kind of amazed that it cares about draft at all, as I would think it would be closer to a forced draft type appliance. However, that doesn't seem to be the case.
In any event, my local hardware store has an 18" section in stock. I will add that on when I can, to see if that gets the cap above any turbulent zone. After that, I may just hang it from a hot air balloon, and run it up really, really high.
I haven't measured the draft, and have no clue as to how I would do it.
I have been studying the vapor plume coming out of the chimney, and I think I just put the chimney in a touchy place. There are tall trees all around, and the structure is a large barn with a fairly steep roof. It seems as though the chimney is in a kind of air pocket. It is doing much, much better with the added height, but with gusts from the wrong direction, it still wants to curl downward, although 95% of the time now, the smoke trails up nicely out of the top. On a clear day or with the normal breeze from the west, there is no problem at all, and I have been burning since Oct with only 2 times where I have had this lazy flame/smoke issue. I don't know if the Eko is more or less sensitive to poor draft instances than any other wood burner. With the blowers and the sealed chambers, I am kind of amazed that it cares about draft at all, as I would think it would be closer to a forced draft type appliance. However, that doesn't seem to be the case.
In any event, my local hardware store has an 18" section in stock. I will add that on when I can, to see if that gets the cap above any turbulent zone. After that, I may just hang it from a hot air balloon, and run it up really, really high.
Try finding a wind directional cap AKA a "rooster tail" the cap always twists to face away from prevailing winds, increases draft wonderfully. I used to get them from a guy in Washington state, Stevens , I think was the name of his company. The guy had a great product, but was to hit or miss for me to keep dealing with him.
Hey, clarkharms...
Just to clarify on 10'-2'-3'. The chimney must extend a minimum of 3' above the roof. On a flat roof if you meet this requirement you are fine. On a pitched roof the chimney must extend above the roof 2' within a 10' radius from where the chimney penetrates the roof in addition to also meeting the 3' minimum. On a steep roof that can mean a subsatntial amount of chimney pipe extending up from the penetration, more than 5' and the manufacture I used requires a roof guy(a strap that attaches from the chimney to the roof, not a person who works on roofs). I do believe these code requirements are good because it helps ensure the chimney won't be effected as much by wind currents caused by the roof as wind passes over the roof
A quick rule of thumb for solid fuel (Class A) chimney clearances...to approximate the 10'-2'-3' requirement.
Take the top number of the roof pitch, multiply by 10 & add 24" to it.
As an example, say we got a 7 on 12 pitch..
Take the 7 & multiply x 10 = 70"
Now add 24" to the 70 & you get 94" out of the roof...
This formula will get you close enough to meet code...
It doesn't exactly work for a flat roof, but you need to be 3' minimum out of that one anyway...
Just to clarify on 10'-2'-3'. The chimney must extend a minimum of 3' above the roof. On a flat roof if you meet this requirement you are fine. On a pitched roof the chimney must extend above the roof 2' within a 10' radius from where the chimney penetrates the roof in addition to also meeting the 3' minimum. On a steep roof that can mean a subsatntial amount of chimney pipe extending up from the penetration, more than 5' and the manufacture I used requires a roof guy(a strap that attaches from the chimney to the roof, not a person who works on roofs). I do believe these code requirements are good because it helps ensure the chimney won't be effected as much by wind currents caused by the roof as wind passes over the roofA quick rule of thumb for solid fuel (Class A) chimney clearances...to approximate the 10'-2'-3' requirement.
Take the top number of the roof pitch, multiply by 10 & add 24" to it.
As an example, say we got a 7 on 12 pitch..
Take the 7 & multiply x 10 = 70"
Now add 24" to the 70 & you get 94" out of the roof...
This formula will get you close enough to meet code...
It doesn't exactly work for a flat roof, but you need to be 3' minimum out of that one anyway...
Hey, clarkharms...
You're welcome! I use it all the time when a customer comes in & wants to cost out a woodstove with a new Class A chimney system...
As long as they know the pitch of their roof I can get them close...
It's pretty surprising how many homeowners don't know what the pitch of the roof on their house is or how to measure it...
You're welcome! I use it all the time when a customer comes in & wants to cost out a woodstove with a new Class A chimney system...
As long as they know the pitch of their roof I can get them close...
It's pretty surprising how many homeowners don't know what the pitch of the roof on their house is or how to measure it...
humpin iron said:
I was a full time mason for years but I only do it now and then for extra money now. Not sure what the codes are in your area but around here that is how everyone builds chimneys. It easily passes any building inspection with no problem. I can see a dozen chimneys from my upstairs window and not one is OVER the peak of the roof. The cap is a very good point though. If you dont have a cap, your chimney could backflow pushing the smoke down the chimney rather than pulling it out.
I have had the same issues you describe with both the EKO and my PE woodstove. I am in the worst possible location for downdraft: at the bottom of a hill (1000') next to the water and surrounded by tall trees. The wind sweeping down over the tops of the trees naturally downdrafts to the house all the time. My solution, after much experimenting with taller chimneys, shorter chimneys , etc. was to purchase a venturi chimney cap. Cost was about $200 and it is designed to produce a negative pressure in the stack no matter what direction the wind is blowing. It works beautifully, but requires frequent cleanings. It is the only part of my PE chimney that ever gets any creosote buildup. I usually clean it every two months in winter.
When I decided to put the EKO in, it was a no-brainer; I put up the chimney to code, then got the venturi cap. No draft issues, even when the smoke is blowing straight down to ground level. The caps are worth every penny if downdrafting due to location or roof pitch is an issue.
See below.
http://www.inandoutlifestyles.com/vastchcap.html
When I decided to put the EKO in, it was a no-brainer; I put up the chimney to code, then got the venturi cap. No draft issues, even when the smoke is blowing straight down to ground level. The caps are worth every penny if downdrafting due to location or roof pitch is an issue.
See below.
http://www.inandoutlifestyles.com/vastchcap.html
GKG- National building codes says a chimney must extend 2 feet above anything within a 10 foot radius, as well as be 3 feet above where it exits the roof. It doesn't necessarily need to be taller than the peak, as long as it meets the 10-2-3 requirement.
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