Is EKO the right stove

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TRACTORMAN

New Member
Jan 29, 2008
9
NW WI
Hi, i'm new here been sitting in for a few days. i've been thinking about an EKO possibly a 40. Talked to the folks at Cozy Heat briefly. My house a three bedroom ranch,1300 square feet,2+4 walls lots of windows. I have hydronic baseboard heat with three zones I occasionally heat the basement. If i go with the gassifier i thought i'd start out with it in the basement and think about moving it out side at a later date. I've been thinking up lots of questions as i'm total DIY.Any one have any thoughts as to how long one of these stoves will last.What is the warranty on these units and what parts are replaceable.There seems that there's a lot of tinkering but can i just throw wood in it and forget it.Just a couple questions to start with and thank you Dan.
 
TRACTORMAN said:
Hi, i'm new here been sitting in for a few days. i've been thinking about an EKO possibly a 40 . . . three bedroom ranch, 1300 square feet . . . baseboard heat with three zones . . . heat the basement. If i go with the gassifier i thought i'd start out with it in the basement and think about moving it out side at a later date . . . how long one of these stoves will last . . . warranty . . . parts are replaceable.

EKO 40 owners can respond directly on that gassifier. I have a Tarm Solo Plus 40 (140,000 btu rating). Assuming the EKO has similar capacity, I think this would work very well for you. I'm a little further north in MN than you are, so we run a little cooler than you in winter. Heck we're only headed to -25F tonight with much colder windchills. Almost a heat wave compared to the past couple cool spells.

No wood unit that I know about is throw in a few logs and forget. But, with a sufficient water storage system, I think you can get to one firing per day most of the time, occasionally two firings, and a lot of the time firing only once every 2-3 days or so. A big advantage of the basement install is all heat from the unit itself is delivered to an area you want to heat. This is really nice.

The Tarm has pro-rated warranties ranging from 3 to 20 years; the only replacements likely needed (I hope) may be the refractory and the door seals; and how long everything really lasts lies in the future for me, as I installed my unit only last Sept. Couldn't be much more pleased than I am.
 
Welcome Tractorman!

I've got an EKO 60. Things I think you can expect to replace are the refractory blocks/bricks in the lower chamber. I'm on my third season, and they are starting to crumble. I think that will be the same regardless of brand.

These things are HEAVY. So I'm guessing that once you get it into your basement, you are not going to want to move it. If you need an ASME stamp to put it in your house, the EKO may not work for you. I think the Tarm is, or can be, ASME stamped? Plus, you should check for any local code restrictions. Mine is outside, so I didn't have to worry about this, and I could be a little off here. Just check before you buy anything.

As mentioned above a storage tank is really helpful.

Unless you have an easy way to get wood into your basement, having the boiler in a shed is very nice. No dirt, ash, or smoke in the house.

Good luck and keep us posted of your progress.
 
TRACTORMAN said:
Hi, i'm new here been sitting in for a few days. i've been thinking about an EKO possibly a 40. Talked to the folks at Cozy Heat briefly. My house a three bedroom ranch,1300 square feet,2+4 walls lots of windows. I have hydronic baseboard heat with three zones I occasionally heat the basement. If i go with the gassifier i thought i'd start out with it in the basement and think about moving it out side at a later date. I've been thinking up lots of questions as i'm total DIY.Any one have any thoughts as to how long one of these stoves will last.What is the warranty on these units and what parts are replaceable.There seems that there's a lot of tinkering but can i just throw wood in it and forget it.Just a couple questions to start with and thank you Dan.

Welcome to the forum and to the boiler room. Lots of people here have experience and opinions that may be helpful to you.

I have an EKO 25 and I'm on my third season with it. There are a few things you'd want to make sure of to prolong the life of any boiler:

1) Make sure that the cold inlet stays above 130 degrees to prevent condensation inside the boiler. Prolonged operation in a condensing situation will cause corrosion from the smoke chamber side in the inlet area.

2) Make sure that the water in the boiler and associated plumbing is pressurized and is not changed / replaced. Fresh water has dissolved oxygen which causes corrosion from the water jacket side. Every gallon of fresh water eats a few more iron molecules.

3) Make sure that any PEX plumbing has an oxygen barrier to keep oxygen from infiltrating through the plastic.

4) Keep the boiler in an area that's not subject to wide temperature swings, especially if it's outdoors. A thousand pounds of cold steel can attract a lot of condensation on a warm and humid day.

Other free advice, and worth every penny: do a heat load calculation and buy the smallest boiler that meets you needs. Bigger is not better. A small boiler can burn efficiently for much longer periods without having to idle.

You haven't mentioned heat storage. It's something you should at least consider. I started without it and added it after my first season.

I've attempted to collect communal wisdom from this site and other places and compile it into a rough decision guide on my site. It's still unfinished, but may be of some help.
 
Weight - good comment on basement install. The Tarm Solo Plus 40 weighs about 1000 lbs. Need the pervasive but elusive 800 lb gorilla to move it.
 
Welcome to the Boiler Room, TRACTORMAN. I'm very happy with the EKO 60, but I'm sure the 40 (or maybe even the 25) would work well in your situation.

There are surprisingly few moving parts on these boilers and not much that I can see that can go wrong. The electronics are all in the controller, which is a simple plug-in replacement and can be swapped out with new models as they become available.

The EKO has a couple of features that make it easier to use and maintain than some other boilers. For one thing, it has movable turbulators in the heat exchange tubes that allow you to keep the tubes clean by periodically yanking on a handle. The controller has a "puff" mode that kicks the blowers on every 10 minutes or so (it's adjustable) to keep the coals live during idle periods. And the new controller allows you to set the boiler temp as high as 195 (not recommended without hot water storage).

I think the EKOs come with a five-year warranty. They're imported from Poland by New Horizon Corp., which must have hundreds of units installed in the field by now. Good people to work with, as are the folks at Cozy Heat.

The Tarm is also an excellent choice. If you have wood already cut and ready to burn, be sure to check the wood length requirements for any boiler you are considering, as they vary.

Econoburn also has a boiler comparable in design and pricing to the EKO and Tarm lines. You can click the bottom banner for more information about that U.S.-made gasifier. I've never seen one, but have heard good things about their design and build quality.

Anyway, if you're interested in modern wood gasifiers, you came to the right place.
 
Thanks for the welcome.It's -15 with a 25 mph wind, wish i weren't burning gas. I've got a small wood stove in the basement, and it's toasty down there but could use more heat up stairs.Oh yes i have a walk out basement, works good for getting things in and out.I have wood up for next year mostly hard wood cut 16 to 18inches .how do soft woods work in these units? What do the insurance companys think of the gassifiers? I think my info says the 40 will take a 7 inch log seems like alot of splitting. If i could get buy with a 25 would that mean the need for storage and how much? well thats enough questions for now. Thanks again Dan :ahhh:
 
TRACTORMAN said:
Thanks for the welcome. . . mostly hard wood cut 16 to 18inches .how do soft woods work in these units? What do the insurance companys think of the gassifiers? I think my info says the 40 will take a 7 inch log seems like alot of splitting. If i could get buy with a 25 would that mean the need for storage and how much? well thats enough questions for now. Thanks again Dan :ahhh:

The Tarm takes up to 20", but 19" works better. Tarm recommends 5" splits, but I burn some larger splits without a known problem. I think the size of the splits relates to surface area which relates to performance of the gassifers. I burn only pine (red, white and jack), dry, with no difficulty at all. Dry pine tends to burn hotter than some other woods, so I had to give more attention to limiting the forced draft to keep the flue temperature down to enhance efficiency.
 
My EKO 25 is happy with 21" wood. I think it can take 23" without going diagonal.

Something to consider about gasifiers: having a load of all large logs is not good. Most of us are used to thinking that a load of large logs is desirable because it will burn longer. That's true, but it will not burn as efficiently, and you will get less heat than you would if those same logs were split smaller. The ideal fire is short and hot, not long and warm.

Gasifiers depend on having enough exposed surface area to generate the flammable gas that's then burned in the secondary combustion. If you have all big pieces, you'll get less secondary combustion. By the same token, a load of really small pieces, especially with a lot of softwood, will generate too much flammable gas and you'll get puffing.

There's a sweet spot there somewhere. I hope to do some instrumented burns to get a better handle on it, but my gut says that if you have pieces larger than about 4", you want to throw a few smaller pieces in with them. The drier the wood, the larger you can get away with. I would never use a 7" chunk.

The highest measured efficiency numbers for these boilers are obtained using wood chips. Doesn't necessarily mean that other forms aren't as good, but that's what was used to obtain the 90% test numbers.
 
It's good to have a mixture. You can put much bigger chunks than 7" in the EKO but, as nofossil explained, that's not always the best approach. I think you can get 30" long chunks in the 60.
 
If I have a big, notty piece that I can't split any smaller, as long as it goes through the door, it gets burned. But, I do put some small pieces under it, then all around it to try to balance it out. Seems to work OK.

Speaking of chips. I usually get a load of logs delivered. After cutting them, the ground has a nice layer of saw chips. Every year I think "How can I collect them up without stones or dirt, keep them dry, then burn them next year? Seems like a shovel full of those chips, if they were dry, would work very nicely in each load. Anyone else try to capture these chips and use them?
 
A little theorizing here on size of wood splits. One of the principles on which gassifiers operate, at least the Tarm, is controlling the oxygen input through controlled draft. On this principle, size of wood splits should make no difference. The supply of oxygen limits the burn.

Also, the size of splits should have no effect on the length of the burn. Only the mass of wood in the firebox, with limited oxygen supply, would control the length of burn. So, the more dense the wood in the firebox, the longer the burn. This means that smaller splits will burn longer than larger splits because less empty space between splits. Or similarly, large and small, to eliminate gaps, will produce longer burns.

Next, if above is true, why smaller splits? I think it has to do with the size of the firebox and the design and sizing of the refractory - gassification area. Smaller splits have more surface area than larger splits. The greater surface area likely is related to maintaining an adequate burn, with limited oxygen, in the firebox to produce sufficient wood gas which then is burned in the gassification refractory.

I suspect that with a different design combo of oxygen supply, firebox, and gassification refractory, plus a few other factors, one could burn any size of wood with highly efficient results. Witness large commercial coal or waste boilers. They also operate at very high gassification temps.
 
Speaking of chips. I usually get a load of logs delivered. After cutting them, the ground has a nice layer of saw chips. Every year I think “How can I collect them up without stones or dirt, keep them dry, then burn them next year? Seems like a shovel full of those chips, if they were dry, would work very nicely in each load. Anyone else try to capture these chips and use them?

For small wood scraps I use paper grocery bags. I fill is about 1/3 full and them roll down the top to seal the bag into a small bundle. I use these all winter long to restart from coals....works great.

So when they ask Paper or Plastic? It's always paper!!

Stay warm!
 
sled_mack said:
If I have a big, notty piece that I can't split any smaller, as long as it goes through the door, it gets burned. But, I do put some small pieces under it, then all around it to try to balance it out. Seems to work OK.

Speaking of chips. I usually get a load of logs delivered. After cutting them, the ground has a nice layer of saw chips. Every year I think "How can I collect them up without stones or dirt, keep them dry, then burn them next year? Seems like a shovel full of those chips, if they were dry, would work very nicely in each load. Anyone else try to capture these chips and use them?

I chip up my limbs That are dryand use them to start a fire and also throw some in on top of the logs. They burn well. I've been doing some thinking on making a grate and a delivery system so I can burn all chips. I've seen one write up on a tarm that was modified to burn wet chips and it was working. The hardest part is the delivery system as you DON"T want a back burn. I just have to many projects and not enough time. I've got a gravity box load of dry chips to experment with and hope to start playing with it this spring.
leaddog
 
Maybe i should chip all my brush piles! I imagion there would be a magic size for the storage based on the load but then that will change with the temp. i was thinking 800 to 1000 gallons. With an un pressurizid tank can you use pex for heat in and heat out?

Thanks Dan

Regency
STIHL 029
STIHL 084
 
You can use pex in pressurized or nonpressurized applications. For pressurized, you probably want something with an oxygen barrier.
 
Chips are great, but hard to dry. I also have bags of chips and bark debris that get burned. A visitor mistook one of the bags for a trash bag and threw in a glass bottle. It melted and created some great gasifier art - I'll have to post pictures.
 
I put the bark sweepings in paper grocery bags and stuff them into the firebox. I have a lot bark and other debris because most of my wood is about 3 years old. The thing I like is that this stuff burns clean, unlike any other woodburner I've ever owned.
 
TRACTORMAN said:
Maybe i should chip all my brush piles! I imagion there would be a magic size for the storage based on the load but then that will change with the temp. i was thinking 800 to 1000 gallons. With an un pressurizid tank can you use pex for heat in and heat out?

Thanks Dan

Regency
STIHL 029
STIHL 084

I cut my large trees in the winter and cut them up. The big wolf trees are out in the open so the limbs dry all summer long. I modified a corn chopper and chip up all the limbs then. The chips a nice and dry that way. I blow them into a gravity box and store them there. It is a lot of work and time to do for the amount of wood you get but I want to clean up all the brush. If you could burn wet chips most places you could get them free from tree trimers or very cheap from saw mills as they chip up most of the scrap. Some day I think there will be a big market for wood chips as a bio-fuel. There is a LOT just rotting down out there.
leaddog
 
Im still figuring out the surface area deal. Just keep a tight wood load then right?

Ive got a 60 Tractorman, this is my 3rd season, and still tinkering with different plumbing and storage ideas. Take time and look at any interesting thread here, cause its full of great info. Take notes on what you like. Many of us wish this forum was here several years ago.
 
Thanks, lots of info here. I've got a question on 25 or 40? If a 25 would heat my house would the only disadvantage of the 40 be wasting some wood ? would one be easier to operate than the other? I'm not retired so being gone for 10 + hours a day i'm looking for something thats not to diffacult to run.

Thanks Dan.
 
TRACTORMAN said:
Thanks, lots of info here. I've got a question on 25 or 40? If a 25 would heat my house would the only disadvantage of the 40 be wasting some wood ? would one be easier to operate than the other? I'm not retired so being gone for 10 + hours a day i'm looking for something thats not to diffacult to run.

Thanks Dan.

I'll venture out on a limb and say yes, the only disadvantage of the 40 would be wasting some wood. Some folks with bigger boilers have blocked one of the two nozzles, turning a 60 into a 30.

My ideal would be a 25 with a bigger firebox and air inlets down low in the firebox like they have them in the Biomax.
 
Hope you are still with me here . How many feet of coil would i need inside the storage tank? And how many feet will a pump push through 1'' pex?

I've got an idea for a tank what can i use for a liner?

Thanks Dan
 
As to selecting a smaller (25) or larger (40) gassification boiler, amount of wood used is a factor, but one of the most important factors is long burn times to maintain a high level of efficiency. I define "long burn time" at a minimum to be one full load of wood which burns to conclusion with no idling of the boiler. Each idling period increases the inefficiency of the burn.

If your heat demand, including storage, can be well met by a smaller boiler, normally that would be the better choice, as installing a larger boiler likely will result in periods of idling and lower overall efficiency. There may be other advantages to the larger boiler in a particular application which outweigh the efficiency consideration.

For a practical example, I have a Tarm Solo Plus 40 (140,000 btu). I heat primarily to storage, and then draw heat as needed from storage. My storage is the boiler (50 gal) + 800 gallons of water. If I draw water from the storage tank at 90-120 through the hx, the Tarm will burn continuously, with return water to the tank through the hx at 150-170. If I draw water from the tank above about 120, in raising the temp of the water to return to the tank I cannot strip through the hx all the btu's the Tarm is producing, and I begin to have idling periods (usually about 15 min), with the periods increasing and longer in length as the temp of the water to be heated continues to rise. Obviously, if my heat demand were higher and supply water to the hx did not go higher than about 120, any idling would be unlikely.

As to a tank liner, EPDM is frequently mentioned as suitable, but see the the post Selecting Tank Linings in the Boiler Room for technical info which may aid in your decision.
 
jebatty said:
If I draw water from the storage tank at 90-120 through the hx, the Tarm will burn continuously, with return water to the tank through the hx at 150-170. If I draw water from the tank above about 120, in raising the temp of the water to return to the tank I cannot strip through the hx all the btu's the Tarm is producing, and I begin to have idling periods (usually about 15 min), with the periods increasing and longer in length as the temp of the water to be heated continues to rise.

What sort of heat exchanger are you using - coils inside the tank? Or a flat plate or sidearm? What about the diameter of the feed pipe from boiler to tank?

I am in the processing of spec-ing out a very similar setup (Tarm Solo 40 with roughly 800 gallons of storage) and was assuming the boiler would never idle until the storage reached full temperature. Not so, huh? Or are there ways to increase the heat exchange capacity to overcome this choke point?
 
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