3 cords of wood in a month?

[noiruuk]

I got my EKO-40 working consistently to heat a 3300 sqft home - I have kept the house temp at 74 for the most part, and the water temp is set at 180. I have no water storage (yet). Over the last month we went through 3 cords of wood...does that sound like an extraordinary amount? I've read the sticky (most of it - it's really long) about tuning the burn, and I was wondering if maybe I've got the primary and secondary air set such that it's burning the wood faster than it should.

Right now I've got the primaries at about 10mm, the secondaries at probably more than 4 turns (it is difficult to gauge that), and the blower at 50% power with about 50% of the intake blocked.

Any burn artists out there have any suggestions?

 

[Eric Johnson]

I've got a 60 and heat about 3,000 sq ft. of moderately insulated old (c. 1865) farmhouse which we keep at 75-80, plus DHW. Looks like I'm on track to burn about 14 cords this winter. This season I did fool around with the air adjustments and got the new controller which allow taking the blowers down to 50%, which I think saves a fair amount of wood.

So no, 3 cords in cold winter weather doesn't sound excessive to me under the conditions you describe. But I can tell you that with experience, you'll learn to burn less.

The important question is: How much are you saving on oil/gas vs. what the wood is costing you?

 

[noiruuk]

Well that's what's eating me. I got the boiler so I wouldn't have to pay the electric company so much. But...with that rate of wood burn, we spent $450 on wood last month. I seriously doubt my electric bill would have been that high (my primary heat is an electric heat pump). Well it would have at 74 degrees, but with just electric I would have kept it at 68 in the house.

Next year I'm hoping will be better, as I'll be using all of my own wood. I have 10 acres of trees with several dozen that were pushed down to make the house. I just have to get out there in time and split a bunch. Kind of off the subject, but do you think if a tree has been down for a year or so, and I split it by May, that it will be ready to burn by November?

 

[Kipstr]

[. Kind of off the subject, but do you think if a tree has been down for a year or so, and I split it by May, that it will be ready to burn by November?[/quote]

All my wood was cut and split in May and my EKO is working just fine. And I think 3 cords of wood in one month is more wood then I would like to handle. I'm one track to burn 4-5 cords for the whole season.

 

[noiruuk]

4-5 cords for the season is where i'd like to be. I just don't know if it's realistic for my situation. Does tank storage help you burn that much less?

 

[Tree farmer]

Next year I'm hoping will be better, as I'll be using all of my own wood. I have 10 acres of trees with several dozen that were pushed down to make the house. I just have to get out there in time and split a bunch. Kind of off the subject, but do you think if a tree has been down for a year or so, and I split it by May, that it will be ready to burn by November?[/quote]

I cut and split mine in may and I have been burning it just fine, some is still on the higher mc side but we had a very wet and poor wood drying summer. Your pushed over trees should make great firewood. I have gone through a little over 3 cords since Nov but I only have around 2k square feet to heat and 2 zones. If you are already running the fan at 50% that should have made the biggest difference in consumption maybe 3 cords is not that bad for what you are heating.

 

[taxidermist]

Ok I have to ask is this face cord or full cords? I could see 3 face cords a month but not 3 full cords way to much wood for a month.

Just my .02

Rob

 

[timberr]

I agree with Taxadirmist, 3 full cords is equal to 450 gal. of heating oil. At that rate I would think you would be filling the fire box every couple of hours. Are you cleaning the secondary burn chamber and getting all of the ash out from under the HX tubes? Is your Eko a Super (Has the turbulator cleaner, silver handle on the left?). Have you been cleaning the turbulators?

 

[Tarmsolo60]

I'm heating 2800sf and all my dhw and I don't think I've hit three full cords yet this winter(close though). It gets pretty cold here and the house is kept low to mid 70's

Have also only used about 30 gallons of oil because it changes over automatically when my storage gets to 130F

I'm hoping you are talking face cords. I did burn more in my first year while still learning better operating procedures and had no storage then, but not that much.

 

[Duetech]

I got my EKO-40 working consistently to heat a 3300 sqft home - I have kept the house temp at 74 for the most part, and the water temp is set at 180. I have no water storage (yet). Over the last month we went through 3 cords of wood...does that sound like an extraordinary amount? I've read the sticky (most of it - it's really long) about tuning the burn, and I was wondering if maybe I've got the primary and secondary air set such that it's burning the wood faster than it should.

Right now I've got the primaries at about 10mm, the secondaries at probably more than 4 turns (it is difficult to gauge that), and the blower at 50% power with about 50% of the intake blocked.

Any burn artists out there have any suggestions?

If those are 4' x 4' x 8' cords I think you are burning too much wood. Does your unit run full tilt 24-7? I have a 40 and consume about .4 cord per week with dense hard wood (in the worst we've had this year) or less if it's not that cold. If you are talking pine and other soft woods I don't think you are too far off the mark with those amounts but not seasoned dense hard wood. What color is your flame? Positional settings are moot in relationship to the color of the flame, that is, if you don't have the color blue your positions aren't tuned positions they are just pieces parts in a random placement. If you have a blue,blue/white, blue/yellow flame you are certainly in the ball park if you have an orange flame you are off mix and need to tweak some more.
How frequently do you load?
How long are your burns?
Are you getting any idle time?
What type of wood are you burning and at what lengths?
Do you know what your moisture is at?
Is your unit in a heated or unheated building.
NOTE: NOTE:NOTE: If your secondaries are too wide you will blow cool air right up your tubes and actually steal heat from the water even if you have a blue flame. Secondaries can be two faced, they can be your best friend or your worst enemy. Random arbitrary example: you need 4 cfm to achieve max high temp but your unit is dumping 12 cfm that is 8cfm at room temperature which is 2000 degrees cooler than your peak efficiency. What will your temperature be when it gets to the tubes in your exchanger? What if that 8 cfm only mixes 20% with your flame to turn it blue but the rest takes up 66% or 50% of your tube space? Secondary air should only be supplied in the amount necessary to achieve the hottest flame. For my unit (old controller) I have to run volume way down to achieve a gentle pressure with primaries then add secondary air until I get a blue flame (not enough volume at this point I am just getting ratio). Only then can I turn up the volume but even at these blended levels I can supply too much air and rob heat from the boiler and watch boiler temps plummet while looking at a blue torch. (hard evidence can be seen where the secondaries cut holes in the flame i.e. your flame base is saw toothed). My settings will probably not be yours but for a reference: P@6mm, S@2turns and Blower opening @3/8 to 3/4".
Side note: if you are burning full cords (price wise it sounds like you are) I'd be scared I was going to have to pay the oil man. :grrr:

 

[noiruuk]

Yep those are full cords I'm talking about. I do run 24-7 and we have been keeping the house at 74 and the water temp at 180. I've been having to load probably 3-4 times a day...I certainly haven't gotten to the point where I can put a load in every 10-12 hours. My burns have been of various lengths...I've seen it burn all the way through in less than 6 hours, and another time I've put in a full load at 10pm and at 8am there were still coals (but that has only happened once or twice at most). Most of the wood is oak, and probably (guess) in the 18" range. I have seen it idle, but those times are more rare, as usually I will go down to the boiler (it's in my un-heated basement) and the fan will be on and the temp will be in the 150-165 range - however I have walked down in the morning and twice seen "E2" displayed indicating that it turned off so it wouldn't overheat (190 degrees, I believe). I do not know what the moisture content is at, however the wood has been good and I've been trying to let it sit inside for a day before I use it.

From Cave's assessment it sounds like I could have the secondaries far too open. The flame at the top (coming out of the nozzle) is blue normally, tapering to a yellow...though it's not uncommon to see it orange at times. The secondaries are really hard to judge, and I was of the mind that wider is better, so I was only concerned with too little secondary air and not so much concerned about too much....which apparently was faulty thinking.

Is there a best-known-method for adjusting the primary air, secondary air, blower power, and blower intake %? Like I said I did read the long thread on this kind of stuff, and I set out to try to emulate what I read others had. For example, I set the blower at 50% and the primaries at 10mm, and then tried to adjust the secondaries until I noticed a difference. I can't say that I ever noticed an obvious difference when I adjusted the secondaries...and where it ultimately ended up could best be categorized as a guess. I turn the bolt clockwise until I feel it kind of scrape against the secondary tube, and that would be 0 turns, correct? I had been gauging from that point as full 360 degrees in the counter-clockwise direction as a turn, and tried to put it at something around 4 turns. Maybe it would be better to try to gauge it by the flame? But, like I said, I hadn't noticed any obvious change...is there a better technique for judging that? Should the blue-to-orange effect on the flame be very obvious?

 

[Tarmsolo60]

I helped a friend install an eko40 but am not familiar with all the settings. Do you monitor your stack temp with a probe thermometer, that will tell you if a lot of heat is going up the stack because of air settings or if the heat exchangers are dirty. My first year my stack were high because of improper air settings. Maybe other eko owners can tell you what they are running for stack temp.

On the one I helped install the factory had the thermostat contacts jumpered. Could this be making your circulator run too much? With your electric heat pump I'm assuming you have a hot water coil in some duct work for your boiler,does the circ run constantly?

 

[Rob From Wisconsin]

This is all making me very sad, but not surprised.

My brother-in-law also has an outdoor boiler.
A few years back I helped him cut & split 5 Full Cords
of Hard Maple/Ash. It only lasted him 1 1/2 months before it was gone!
Than amount would have lasted me almost 2 seasons in my woodstove!!

On a similar note, our neighbor also has an outdoor boiler, along with approx.
40 acres of heavily wooded land (well, at least it was..). After one year, and 12-15 Full Cords
of wood used-up, he's now travelling about & scrounging whatever wood he can from
people who are willing to let him thin out their woods. It's become more than a Part-time job.

With the above in mind, and pointing the finger at Boiler Mfr's that put-out very inefficient
units (yes, there a some out there that that are somewhat efficient, but even those will probably
put you down 8 cords), are we heading in a direction that will deplete our wood supply??

My Soap Box & 2-Cents worth.......

 

[Tarmsolo60]

This is all making me very sad, but not surprised.

My brother-in-law also has an outdoor boiler.
A few years back I helped him cut & split 5 Full Cords
of Hard Maple/Ash. It only lasted him 1 1/2 months before it was gone!
Than amount would have lasted me almost 2 seasons in my woodstove!!

On a similar note, our neighbor also has an outdoor boiler, along with approx.
40 acres of heavily wooded land (well, at least it was..). After one year, and 12-15 Full Cords
of wood used-up, he's now travelling about & scrounging whatever wood he can from
people who are willing to let him thin out their woods. It's become more than a Part-time job.

With the above in mind, and pointing the finger at Boiler Mfr's that put-out very inefficient
units (yes, there a some out there that that are somewhat efficient, but even those will probably
put you down 8 cords), are we heading in a direction that will deplete our wood supply??

My Soap Box & 2-Cents worth.......

Your talking OWB the EKO is a indoor gasifier.

When the OP gets his problem figured out he will burn much less wood, I heat 2800sf evenly in the mid 70's with DHW with about 6 cords.

 

[noiruuk]

I helped a friend install an eko40 but am not familiar with all the settings. Do you monitor your stack temp with a probe thermometer, that will tell you if a lot of heat is going up the stack because of air settings or if the heat exchangers are dirty. My first year my stack were high because of improper air settings. Maybe other eko owners can tell you what they are running for stack temp.

On the one I helped install the factory had the thermostat contacts jumpered. Could this be making your circulator run too much? With your electric heat pump I'm assuming you have a hot water coil in some duct work for your boiler,does the circ run constantly?

You are correct, I have a hot water coil in my plenum to exchange the heat. Basically I have a loop from the boiler, to the domestic hot water tank side-arm exchanger, to the plenum, and back to the boiler. When the boiler water temp reaches 145 degrees it circulates throughout the loop non-stop...I am hoping that's pretty standard, as I got the design from the seller of the unit (with reference to the boiler manual).

To answer a previous question regarding the heat exchanger cleaner lever on the side...I do run that back and forth several times every loading. I have recently been keeping the lever toward the rear of the unit, however after looking at what it is and what it does, it doesn't seem to me that the position of this lever would make a difference one way or the other. Am I wrong?

 

[Nofossil]

My $0.02:

If you're overheating from time to time, then you're also probably idling a lot. Maintaining constant house temp without storage can create a lot of inefficiency.

I don't know what your heat load is, but the EKO 40 is probably way too big on all but the very coldest days.

Perfecting your technique might make a big difference. Here's the goal: Never have the boiler idling. Without storage, the only way to do that is to have a series of small fires matched as well as possible to the house's heat loss.

I did this for a season and burned less that 3.5 cords. Here's what I did:

- Let the house temp fall to the lower comfort level (about 68 degrees) by late afternoon / early evening.
- Open the fan shutter to 50% (full throttle for mine). Build a fire that has enough fuel to last 1-2 hours. Let it die down. This should get the house back into the comfort zone and leave plenty of coals for the next step.
- At bedtime, close the fan shutter to about 3/4". Load it up with enough wood to last 4-5 hours. That will heat the house for the night and hopefully leave coals in the morning.
- In the morning, restart the fire if necessary. If I'll be around during the day and it's cold, I'll add just enough wood for an hour burn. I'll repeat in a few hours as needed.

The basic idea is never to put in a lot of wood at one time unless the heat load is very high. You want a series of short hot fires with quiet time in between.

The fan shutter is in effect a throttle and can increase or decrease the BTU/hr output of the boiler to some extent. Close it too far and the nozzle velocity drops to the point where you get puffbacks. Some folks close off one nozzle on the larger boilers to reduce the heat output.

If you have the new controller, I think you can adjust the amount of time the fan runs after the outlet temperature falls off. You'd like the fan to shut off after it's down to a bed of coals so that you can restart by just throwing in more wood.

This takes a bit of futzing around and learning to estimate demand, but it's not too big a deal if the boiler is inside. In my view the biggest advantage of storage is that you can just build one fire at whatever time is convenient, and the house stays the same temp all the time.

 

[leaddog]

I have a eko-80 and I don't burn that much. I don't know what is happening but I don't see how you can put that much wood thru your unit. Even with bad gasification it shouldn't burn this much. I'm thinking there must be several problems.
If you are burning oak it may be that the moisture is high. Oak takes longer to cure than most other woods
I don't know what your heat load is but you may be so undersized that you aren't running your boiler temp high enough to get good gasification. If your return temps are low your boiler can't get up into the 180* range. I have mine set so my outlet water is 185*. My pump doesn't come on untill the boiler temp is 170* and no water leaves the boiler untill it is 185* and then I control the water outlet to hold that temp. It runs more efficient that way do to a combination of things. Higher intake air temp, higher primary chamber temp,(better breakbown of the wood into gas).

I think that if you can get it dialed in you will find out you will use alot less wood.
Are you getting bridging?
What color is the sides of the secondary chamber walls?
Do you shake the turbulator lever each time you fill?
When you open the bottem door will you find that it is gasifing or are you getting smoke---at different times in the burn?
The answer to these will give us a idea what is happening.
leaddog

 

[noiruuk]

My $0.02:

- Let the house temp fall to the lower comfort level (about 68 degrees) by late afternoon / early evening.
- Open the fan shutter to 50% (full throttle for mine). Build a fire that has enough fuel to last 1-2 hours. Let it die down. This should get the house back into the comfort zone and leave plenty of coals for the next step.
- At bedtime, close the fan shutter to about 3/4". Load it up with enough wood to last 4-5 hours. That will heat the house for the night and hopefully leave coals in the morning.
- In the morning, restart the fire if necessary. If I'll be around during the day and it's cold, I'll add just enough wood for an hour burn. I'll repeat in a few hours as needed.

The fan shutter is in effect a throttle and can increase or decrease the BTU/hr output of the boiler to some extent. Close it too far and the nozzle velocity drops to the point where you get puffbacks. Some folks close off one nozzle on the larger boilers to reduce the heat output.

If you have the new controller, I think you can adjust the amount of time the fan runs after the outlet temperature falls off. You'd like the fan to shut off after it's down to a bed of coals so that you can restart by just throwing in more wood.

This takes a bit of futzing around and learning to estimate demand, but it's not too big a deal if the boiler is inside. In my view the biggest advantage of storage is that you can just build one fire at whatever time is convenient, and the house stays the same temp all the time.

Good stuff, Nofossil. Is there a different effect when I use the "fan shutter" (which I assume is the sliding panel that blocks/opens the fan air intake) versus the actual blower power? I am guessing I have the newer controller, since I can adjust the fan power in 10% increments from 50-100. I've currently got the fan at 50% power, and the shutter at about 50% closed.

Smaller, more frequent fires is an idea that I will try, also. Up to this point I have been loading it full every time.

The good thing from all this feedback is that it sounds like I *should* be able to significantly reduce my wood use. That's a relief, and makes the last month wood expense feel less like a waste, and more like a learning experience.

Anyone have any suggestions on a good method for determining the secondary air flow? I have a mind to keep the fan power at 50%, open the shutter all the way (100% open), set the primaries at something less than 10mm (where I have them now), close the secondaries and get a flame going and slowly open the secondaries. Sound about right?

How important is it that both secondaries be equally open?

 

[Tarmsolo60]

Does anyone think that running the circ to the hot water coil only on a call from the house tstat instead of when the boiler is hot enough would stop some boiler cycling some. yes, it would probably idle more but it would fan the fire less often?

 

[Fred61]

Everyone says that you will burn less wood after a while and that's true. The one problem that comes to mind after reading the above posts is that as soon as someone starts burning wood, they try to raise the temp in their living space to an unreasonable high temp. It's like as soon as we start burning wood all other criteria is out the window. It's like the new vegetable gardener who's first priority is to raise a tomato the size of a small watermellon or one who's shape looks like his brother-in-law.

When I started reading about solar and other alternate energy in the early seventies, the general rule was to keep the temperatures as low as possible to avoid loss and to absorb more energy. It takes a tremendous amount of energy as we go higher in temperatures.

If I kept my living space at 74* I would be stripping down to my skivvies. I do heat with radiant floor and that's a big help but my house is well insulated which not only slows heat loss but protects the body from radiational cooling. In a well insulated home a person can feel comfortable at 70* but that same person may need to have the temp at 72* to achieve the same comfort level in a poorly insulated home. A simple shade on a window with almost no R value will stop some of the radiational cooling on a body. Drafts and leaks are not the only players.

Perhaps the money spent on more wood and more hardware for the heating system could be put on conserving the heat we are now making.

 

[noiruuk]

Are you getting bridging?

What is bridging and how do I determine if I'm getting it?

What color is the sides of the secondary chamber walls?

The bottom chamber walls I have never noticed any color change...black I would guess is the best description. The flame shooting out of the nozzle does, however, make the U-shaped ceramics glow red (at their top at least).

Do you shake the turbulator lever each time you fill?

If by "shake" you mean run the handle back and forth from front to back (the natural motion of the lever), then yes. I don't really rattle the lever around or anything. Is there a technique to using that lever?

When you open the bottem door will you find that it is gasifing or are you getting smoke---at different times in the burn?

I'm going to play dumber than I actually am, and ask this question: Am I seeing gasification if when I look in the bottom chamber there is flame shooting out of the nozzle? If so, then yes I do see that every time. If you can get that flame shooting out and still not be gasifying, how do I determine that? Oh, and no I can't say I see a lot of smoke coming out of the bottom chamber (particularly after getting the chimney cleaned last week).

 

[stee6043]

Everyone says that you will burn less wood after a while and that's true. The one problem that comes to mind after reading the above posts is that as soon as someone starts burning wood, they try to raise the temp in their living space to an unreasonable high temp. It's like as soon as we start burning wood all other criteria is out the window. It's like the new vegetable gardener who's first priority is to raise a tomato the size of a small watermellon or one who's shape looks like his brother-in-law.

When I started reading about solar and other alternate energy in the early seventies, the general rule was to keep the temperatures as low as possible to avoid loss and to absorb more energy. It takes a tremendous amount of energy as we go higher in temperatures.

If I kept my living space at 74* I would be stripping down to my skivvies. I do heat with radiant floor and that's a big help but my house is well insulated which not only slows heat loss but protects the body from radiational cooling. In a well insulated home a person can feel comfortable at 70* but that same person may need to have the temp at 72* to achieve the same comfort level in a poorly insulated home. A simple shade on a window with almost no R value will stop some of the radiational cooling on a body. Drafts and leaks are not the only players.

Perhaps the money spent on more wood and more hardware for the heating system could be put on conserving the heat we are now making.

+1, Amen, Preach On, and all of that good stuff. I know several folks that upon getting a wood burner up and running would keep the house in the mid 70's and pretty much hold that temp 24/7. I for one still use a programmable thermostat to drop my house temp to 63 at night and during the day when only the dogs are home. The temp comes up to 68 just before I get home from work and then again goes up to 71 a few hours later to take us through the evening hours/dinner/TV watching. I'd keep it even colder at night but I've found that anything less than 63 and my blower/pump have to run too hard to get caught back up. The jump from 63 to 68 is quick and 68 to 71 takes no time since the boiler is always running by this time....

 

[noiruuk]

We have a tight house - it was built last May. I have set my programmable thermostat similar to what you mention, in that it'll be cool during the sleeping hours and warm up as we're waking up, so I'll see how much of a difference that will make. I appreciate the suggestions on better insulating the house and such, however I'm really looking for advice on the boiler operation - as I believe I just am too inexperienced at this point to be confident that I have the set-up just right. All good suggestions, and we are working to that end, but configuring the boiler is something I can try this weekend without spending more money on drapes

 

[leaddog]

ok, Bridging is when you have had a fire going for a period of time and you open the upper chamber you can see the nozzels with wood on top, The coals have burnt away from the nozzels. also the wood is hanging up and not falling down. This this caused by a couple of things, (1) to large of pieces and not enough coals (2) Not enough coal bed with wet wood on top. (3) to much secondary air under to much force blowing up into the primary chamber.

If your bottem chamber walls are black and not a lite gray or gray then you are not getting good gasification. You may be getting flames out the bottem but are not getting complete combustion. This again leads me to think the wood is 30% or more. At that point you are using 1/3 of you heat to evaporate the water and you are cooling the gas flame. With not dry wood you can never get blue flame untill the moisture is boiled out and even if you are getting flame out the bottem it will be a cooler flame and leave carbon on the walls (black)

shaking the turbulator levers is just moving it back and forth a few times and it sounds like you are doing this right.

Going back to your saying that it as over heated a couple of times also leads me to believe that those times you had the boiler running right but was over filled for your heat load. You happened to get into some dry wood, had a good coal bed (3 to 4in) and it started to really gasify. I don't know what your overheat setting is set on your controller is but I think the default is 210* Unless you didn't shut the damper TIGHT even then the boiler shouldn't have over heated as the fans should have shut down and with the pump running you wouldn't have over heated. So another thing to look for is if your damper is closeing completely. You may be just sending the heat up the stack. The older ones had a gasket on the damper but the new ones don't have anything just metal to metal and they need to shut tight.

Try using some small splits like about 2 to 3in dia. that you have and see if that helps. They will burn faster and hotter and give you a good coal bed and then put some of the larger pieces on top.
Another thing, if you are used to burning wood try and forget everything you thought you knew about burning wood and starting fires. IF YOU DO NOT HAVE A GOOD COAL BED YOU WILL NOT GET GOOD GASIFICATION AND IF YOU FILL THE UPPER CHAMBER UP WITH WOOD IF WILL BURN LIKE A OWB AND SMOKE. REMEMBER, THESE BOILERS WORK BY GASIFING THE WOOD IN THE UPPER CHAMBER JUST ON TOP OF THE COALS AND THAT GAS THEN IS FIRED BY FLOWING THRU THE COALS AND BEING MIXED WITH SECONDARY AIR. If you have alot of fire in the top you not gasifiygood.
hope this helps and keep us posted and we'll have you burning down soon.
leaddog

 

[noiruuk]

awesome stuff and very much appreciated! I am entering this weekend with a little bit more knowledge and a re-energized sense of confidence that I can make this beast burn like I want it to. I will definitely respond with my results.

This bridging, as you describe...yes, I can say I've seen this often. Far too often I'll go check on the boiler and it says "Fuel", and I open the top chamber and there's wood there but not a whole lot of coals under the wood. I can usually remedy this by sticking the poker down there and fussing some coals from the edge down to the nozzle, then things usually catch on and it resumes its over aggressive use of my wood.