Gasification Boiler Piping Scheme

[Eric Johnson]

I resisted the idea of water storage at first, too, mainly because you can spend upwards of $3,000 for an 800 gallon tank and heat exchangers. Actually, probably more than that now, given the price of copper. And I couldn't see spending that in addition to the cost of the boiler. Plus, I've heated with various conventional wood boilers for about 15 years, and never used storage, except the small amount provided by a 40-gallon water heater.

But--gasification is a slightly different animal from a conventional wood boiler. It has a nice water jacket, but no bed of coals sitting on the grates to constantly generate heat after the fire has died down. The most efficient, cleanest-burning way to run a gasifier, as I understand it, is full-out, balls-to-the-wall. In most applications, that's probably fine without storage when it's below zero (F), but not when it's in the '20s, '30s and '40s. During warmer weather, you're ahead to run it full-out (say) once or twice a day, and store the heat. And in very cold weather, you've got an additional 400,000 btus sitting in the tank in case you need it.

What sold me on the idea, however, was the prospect of firing the boiler up once a week in the summer, banking the heat in the tank, and then living off free DHW for the rest of the week (or however long it takes to deplete the tank). Over time, the cost of the tank comes back in the form of unlimited, free hot water, plus all the additional benefits (mostly in the form of flexibility) that having a hot water storage tank offers.

But the bottom line is that you can run an EKO or a Tarm without hot water storage. I don't know about the Tarm, but they tell me that the EKO will idle well, so it should be fine. If you check out the FAQ at the Horizon website, they say that the only real downside to running without a tank is that you will use more wood. I was going to buy the boiler and think about putting in the tank later, but when I took a hard look at my setup, I decided I could do the tank for around $500. So that's what I'll be doing this weekend.

 

[keyman512us]

Eric:

Good points, elk. The greenhouse loop is not really diagrammed completely. What I need is a reservoir (along with a PRV and gauge), since there’s not very much fluid in that loop to begin with. If I use cast iron radiators instead of baseboard for radiant heat, then I probably don’t need a res. I don’t like messing with glycol, but the greenhouse is just too vulnerable to freezing up, and I don’t want to have to drain the system every time I decide to shut ‘er down. I’ll probably just put in a fill tube and top it off as needed, instead of trying to put in a domestic water feed.

Making the "loop" for the greenhouse? Need a resevoir? You got me thinking on that one Eric...When you proposed your original "Propane tank storage idea" for the heated water...

Here's one for ya:

I use one of these type of tanks as a "portable air tank" and sometimes it gets used on "roofing jobs" as a "rooftop reservoir" to run two to three "air gun nailers"...works slick! Before anyone "chimes in" on pressurizing an old tank the one I use was "hydro-tested" by a friend who is licensed to hydro-test fire extinguishers. It holds 130PSI of compressed air...so a 30PSI (heating system design pressure) rating is no problem.

The "greenhouse loop" is going to be a "separately derived" system filled with Glycol? How about an old "forklift propane tank" for a "fill port/reservoir/expansion/manifold tank"??? Plenty of 3/4" fittings to utilize, great way to get the glycol into the system...even a 3/8" fitting for a pressure gauge...
The beauty is you can do everything you need to for short $$$.
These tanks "after the rated service life" expires (time limit set in stone...not by actual fitness for use) are "stripped" of their fill fittings....but are still in "useable" condition. Can be found just about anywhere that re-cycles or processes scrap. I got this one at a local scrap yard...that had over two dozen in the pile:

 

[Eric Johnson]

I like that idea a lot, keyman. I was thinking about putting a couple of cast iron radiators in the greenhouse (instead of baseboards) and I figured those would work as reservoirs, but an old forklift propane tank would really be the ticket.

 

[keyman512us]

Eric...
Do some searching around your area...I'm sure you can find one to "work with". If you can't...just e-mail me...I'm sure with all the "ports open" UPS would accept the "crated tank for shipment"...if not..I'll throw one in the car and drive out for a road trip.

If I can get some time...I'm going to "set one up" to do exactly what you are trying to do...I gotta get ready to tie the radiant loop in for my shed/workshop.

I'll keep you posted...

 

[kc10ken]

The people I've talked to who have gasifiers, both Tarms and EKOs, say that the best way to do it is fire them full bore. So yes, the tank is where you would store your heat. A guy I talked to who has a similar-sized Tarm and an 800-gallon tank says that even when it's below zero, he loads the thing twice a day, max, and can skip a day when it's in the '30s. In the summer, you can run one load of wood per week for your domestic hot water. The Tarm goes out if it has to idle for too long (i.e., when the tank is fully charged and there's no call for heat from the house). The EKO has a feature that blows the fan every ten minutes or so during idle, so that the coals (allegedly) stay alive during idle, as long as there's wood in the firebox. I suspect it smokes a little when that happens, but probably not very much.

In a way, these are more like conventional gas or oil burners, in that there's no big bed of coals to constantly supply heat. When you make the heat, you have to put it somewhere. Hence the tank. I think it's quite a bit different from an operational standpoint from what I have now.

I'm used to tending the boiler when I'm around, so at first I'll probably get into going out there and putting small loads of wood in it all day long, just to see it work. I have enough room to expand the storage tank from 1,000 to about 2,500 gallons, so I might eventually get into a situation where I'm firing the boiler up once every couple of days during average winter weather and maybe once a day when it's really cold. In the summer, it would be so long between firings for DHW that I'd probably forget to do it and catch hell from my wife for running out of hot water.

The guy with the Tarm says that when the fire goes out, all he does is squirt a little lighter fluid on the charred wood remaining in the combustion changer, hits it with a propane torch, and in a couple of minutes he's back in business. Beats fooling around with paper and kindling. Personally, as I've said before, I'm used to firing the boiler up in the fall and keeping it going until the following spring. But, in the immortal words of my main man, Red Green:

I'm a man.
I can change.
If I have to.
I guess.....

Hi.....just wanted to say I've had an EKO-40 Wood Gasification boiler in my basement for 2 years now and I LOVE IT. It works GREAT...just as advertised and I noticed in your post that you said it "allegedly" keeps the hot coals glowing during periods of idle. There's no allegedly about it.....it works ! When I want to shut my boiler down for cleaning or whatever, it takes 4 days at idle to cool down enough for me to clean it out. If I forget to load it and all the wood burns down, there are ALWAYS hot coals in the bottom of the loading chamber...for days.....that ignite nicely any wood I load into it.

I saved $2800 last winter and $2400 the winter before that!

All my wood is FREE and I LOVE THIS BOILER!

 

[Eric Johnson]

Welcome to the board, kc. I'm really happy to hear about your experience with the EKO. Rest assured, I'll be hitting you up for your thoughts and ideas.

 

[kc10ken]

Welcome to the board, kc. I'm really happy to hear about your experience with the EKO. Rest assured, I'll be hitting you up for your thoughts and ideas.

THANKS!


I'm new to all this so go easy on me, however, I have nothing but GREAT things to say about wood gasification heat after 2 years of heating my house with wood. I'm SHOCKED that more American's are not installing these systems with the price of heating oil and gas being what they are.

Oh well....more free wood for me!

 

[Eric Johnson]

Do you get any smoke at all when the thing is running? How about on cold startup?

 

[kc10ken]

Do you get any smoke at all when the thing is running? How about on cold startup?

NO SMOKE! When the EKO-40 is gasifying properly (man, you oughtta see this thing working...it really is amazing cause it burns at like 2000 degrees F) there is no smoke at all.

On cold start up of course there will be smoke and sometimes at idle as well.

Some advice........ALWAYS make sure your chimney is clean. This thing produces a LOT of creosote. I've already had one chimney fire because of it (nothing major, just singed the insulation I had wrapped around the smokestack in my basement). Our smoke alarms went off so my wife went nuts! I also have a draft inducer installed in the smokestack in my basement, this prevents backfiring and I have found it keeps the boiler from overheating. I don't have a heat storage tank in my system so overheating was a problem when I first got this thing 2 years ago.

ALWAYS keep the combustion chamber clean. Clean it out at least once every 2-3 weeks.

NEVER open the loading chamber real fast while the boiler is running or at idle.....you know what a flashover is? I made that mistake only once....I opened the loading chamber door really fast and the combustible wood gasses flashed over and POOF...almost lost my facial hair ! Open the rear flapper door first, wait a few seconds, then SLOWLY open the loading chamber door, just a crack at first.....give it few seconds......if you see flame inside the chamber then it's OK to open because you already have ignition. If you don't, open the door slowly!

I also installed an additional water circulation pump in the system to help circulate the heated water better. It helped solve my overheating problem and the EKO 40 worked a WHOLE LOT better.

I LOVE this boiler!

 

[keyman512us]

KC welcome to the forum...

Eric:

But, in the immortal words of my main man, Red Green:

I’m a man.
I can change.
If I have to.
I guess.....

...Is Red Green still on???

"...Time to take out the 'Handymans secret weapon..Duct tape'..."lol

"...If women don't find you handsome...they outta at least find ya' handy...Keep your stick on the ice.."

 

[Eric Johnson]

Red's on our local PBS station, but I haven't seen it for awhile, so maybe not no more.

Hey keyman, I'm going to be traveling through Worcester in early May on my way to Maine. If you want to sell me one of those propane tanks, let me know and maybe I'll swing by and pick it up--and check out your boiler. I'm thinking a tank like that would be a great place to hang the PRV, the TP gauge, etc.

 

[keyman512us]

Red's on our local PBS station, but I haven't seen it for awhile, so maybe not no more.

Hey keyman, I'm going to be traveling through Worcester in early May on my way to Maine. If you want to sell me one of those propane tanks, let me know and maybe I'll swing by and pick it up--and check out your boiler. I'm thinking a tank like that would be a great place to hang the PRV, the TP gauge, etc.

I'll send a PM and keep in touch...I registered for the EXPO today...Might be going up to Bangor on either the Friday or Sat...gotta work out the details...my buddy George (of the jungle tree Svc) wants to go...

Please PM me any Info/Itinerary on the EXPO...also/by all means "Don't be a stranger when you venture up this way"..."Traveling Tree folks' are welcome in these here parts"

 

[Nicholas]

Do you get any smoke at all when the thing is running? How about on cold startup?

NO SMOKE! When the EKO-40 is gasifying properly (man, you oughtta see this thing working...it really is amazing cause it burns at like 2000 degrees F) there is no smoke at all.

On cold start up of course there will be smoke and sometimes at idle as well.

Some advice........ALWAYS make sure your chimney is clean. This thing produces a LOT of creosote. I've already had one chimney fire because of it (nothing major, just singed the insulation I had wrapped around the smokestack in my basement). Our smoke alarms went off so my wife went nuts! I also have a draft inducer installed in the smokestack in my basement, this prevents backfiring and I have found it keeps the boiler from overheating. I don't have a heat storage tank in my system so overheating was a problem when I first got this thing 2 years ago.

ALWAYS keep the combustion chamber clean. Clean it out at least once every 2-3 weeks.

I LOVE this boiler!

I am looking into Gasif wood boilers (Tarm, greenwood), but now do to your experiance I am confussed ?? both Tarm and Greenwood claim they produce NO creosote and have a clean burn, clean the fire chamber once a year, etc. ???????
If Your experiance is how they are, Why pay all that money when an OWB will do the same thing ?

I'll have to admit, after Your comments, I have that "back to the drawing board" feeling.
Bruce is not going to like this !!

 

[Eric Johnson]

kc actually owns one, so he's more qualified to answer your question, but here's my understanding of how most gasifiers work:

You get a clean burn when the gasification process is underway, which is to say any time the boiler is operating under load and producing heat. And when it's gasifying, it's also operating at about twice the efficiency of your typical OWB. The only time you're going to get smoke or creosote in the stack is on cold startup (before gasification can begin) and during idle. What happens during idle is that the gasification chamber is bypassed and any smoke generated in the firebox goes up the stack, where it can form creosote. You will also get creosote in the firebox under normal operation, since the creosote-laden smoke lingers there before being pulled down into the gasification chamber, and some of it inevitably sticks to the walls.

So the trick to getting a clean, smokeless fire with a gasifier is to maximize the amount of time that it is running full-bore, while minimizing the idle periods. This is a lot easier with a hot water storage tank or some other heat buffer. You can still run a gasifier with no storage, but you will burn more wood and produce some smoke and creosote, especially during warmer weather. I think the Greenwood gets around the water storage issue with a huge refractory mass built into the boiler. Tarm recommends using a storage tank. There are some design differences between the Tarm and the EKO which makes it easier to start the EKO back up after idle, but with some smoke and creosote as the trade-off. That's my understanding anyway, without having used or seen either in operation.

So to answer your question, the reason to pick a gasifier over an OWB is that for about the same price, you get a clean burn and will use half as much wood.

 

[kc10ken]

kc actually owns one, so he's more qualified to answer your question, but here's my understanding of how most gasifiers work:

You get a clean burn when the gasification process is underway, which is to say any time the boiler is operating under load and producing heat. And when it's gasifying, it's also operating at about twice the efficiency of your typical OWB. The only time you're going to get smoke or creosote in the stack is on cold startup (before gasification can begin) and during idle. What happens during idle is that the gasification chamber is bypassed and any smoke generated in the firebox goes up the stack, where it can form creosote. You will also get creosote in the firebox under normal operation, since the creosote-laden smoke lingers there before being pulled down into the gasification chamber, and some of it inevitably sticks to the walls.

So the trick to getting a clean, smokeless fire with a gasifier is to maximize the amount of time that it is running full-bore, while minimizing the idle periods. This is a lot easier with a hot water storage tank or some other heat buffer. You can still run a gasifier with no storage, but you will burn more wood and produce some smoke and creosote, especially during warmer weather. I think the Greenwood gets around the water storage issue with a huge refractory mass built into the boiler. Tarm recommends using a storage tank. There are some design differences between the Tarm and the EKO which makes it easier to start the EKO back up after idle, but with some smoke and creosote as the trade-off. That's my understanding anyway, without having used or seen either in operation.

Hope I'm not being a pain in the ass by putting my 2 cents worth into this.....if I am, just say so and I'll butt out.

My EKO-40 has been in operation for 2 years now. There were a few bugs to iron out upon initial installation because the plumber I chose to install it had only installed one or two gassifiers prior to mine. Bottom line......it was a learning experience for ALL of us until I got this thing running smoothly.

With a heat storage tank you certainly can run this thing balls to wall full out and then store the heat in your tank....but I do not have tank. The EKO-40 has a computer temperature control system that regulates the blower motor (that blows air into the loading chamber to gassify the wood). I usually keep it set full throttle at 80 degrees Celsius, HOWEVER, if I want a slower burn and a lower temp then I simply set the temp down a little...to around 72 degrees Celsius. This makes the wood last longer but makes your operating temperature lower (so it takes longer to heat your house).

When the EKO-40 is idling, the gasification chamber is NOT bypassed. The smoke created in the loading chamber goes through the nozzle and down into the combustion chamber and THEN up the smokestack via a series of 6 exhaust tubes in the back of the unit. This is why I have found, it is CRITICAL to keep the nozzle (the nozzle is simply a convex shaped rectangular opening in the bottom of the loading chamber) clear and open during idle. Also, when you clean the boiler make sure you clean out the bores of those 6 tubes in the back of the unit. They are easily accessed and buildup does occur.

I do indeed get creosote build up in the loading chamber. I usually clean my EKO-40 about every 3 weeks. The distributor, New Horizon Corp, told me I should never have to clean out the loading chamber....only the combustion chamber....NOT TRUE...at least in MY case. I find creosote build up sometimes as thick as 1/4 " on the loading chamber walls. Maybe I still have to make adjustments to my EKO-40 to avoid this...I really don't know....I'm not an expert.

One other item we could never get right was the Laddomat mixing valve. It never seemed to work as advertised so I took out all the inners (plungers, valves etc.) so all the return water just mixes in. This MAY be the reason for my creosote.....I don't know. i just know that the Laddomat mixing valve never opened and mixed properly and was causing over heating problems and after I took the inners out my over heating problem went away.

Starting my EKO-40 back up after idle or after the loading chamber has burned down to nothing has NEVER been a problem. As long as there are cherry red coals in the bottom of the loading chamber any wood I put in WILL ignite after a period of time. I have found that if I stuff some old newspapers in with the new wood and throw a match in to ignite the newspapers it fires up and come up to operating temperature within minutes instead of and hour or so with no newspaper.

It's been a learning experience to say the least but I still LOVE this boiler. My wife HATES it because of the smell in the basement. maybe someday I'll get lucky and I'll have to choose between the wife and the boiler.......LOL!!

That's my 2 cents.........

Ken


So to answer your question, the reason to pick a gasifier over an OWB is that for about the same price, you get a clean burn and will use half as much wood.

 

[Eric Johnson]

Thanks for clearing that up, Ken. I find your thoughts to be really helpful to my understanding of how this thing works.

Does the wood gas burn when the boiler is idling, or does the smoke just pass through the heat exchange tubes and up the stack unburned? How can it go down through the combustion nozzle if the fan is off?

The Model 60 I'm getting has a handle on the side that allows you to clean the heat exchanger tubes from the front of the unit by moving the handle back and forth. The guy I'm buying it from said you should yank on that handle every time you load the stove.

 

[kc10ken]

Thanks for clearing that up, Ken. I find your thoughts to be really helpful to my understanding of how this thing works.

Does the wood gas burn when the boiler is idling, or does the smoke just pass through the heat exchange tubes and up the stack unburned? How can it go down through the combustion nozzle if the fan is off?

The Model 60 I'm getting has a handle on the side that allows you to clean the heat exchanger tubes from the front of the unit by moving the handle back and forth. The guy I'm buying it from said you should yank on that handle every time you load the stove.

The wood gas does NOT burn when it's idling. I had a problem with backfiring because the flapper door in the back that opens the loading chamber to the smokestack had a bad seal and was allowing air (oxygen) into the loading chamber while the wood was glowing and smoking ....POOF...backfire. I discovered the bad seal during a cleaning and replaced it. I also found that the backfiring problem was worse when I burned small, very dry logs. For some reason my EKO-40 runs GREAT on very large logs of fresh, moist wood.

The smoke created at idle does go down through the nozzle, and then up the tubes and out the smokestack. There is so little of this smoke generated that you barely see it coming out of your chimney outside your house....it's minimal. Are you sure about that handle? My EKO-40 has only one handle on the front left side and it's for opening the round flapper valve in the back of the loading chamber to the smokestack. I've also experienced flashovers when opening that flapper valve. Flashovers seem most prominent right after a gassification (blower) cycle as the EKO-40 goes into idle mode. I'd be REAL careful opening the loading chamber door or the flapper valve right after a gassification cycle because of flashovers.

Those heat exchanger tubes do get clogged up. My EKO-40 came with 3 long iron stokers. One has a round head on it designed for cleaning out those tubes. I clean them about every 3 weeks when I clean out my unit. It's a dirty job....but I've saved well over $5000 in 2 years and since I live out in the middle of nowhere in upstate New York I have enough free firewood to last me into the 23rd century!

 

[Eric Johnson]

Here's the handle on a Model 40. Orlan makes "super" and "standard" versions of the EKO boilers. The "super" has the handle for cleaning the tubes. They tell me that now that's all they import.

Where you at in NYS? As you can see, I'm just south of Utica. I'm the guy with the 20 cords of dry beech sitting in his backyard.

 

[kc10ken]

Here's the handle on a Model 40. Orlan makes "super" and "standard" versions of the EKO boilers. The "super" has the handle for cleaning the tubes. They tell me that now that's all they import.

Where you at in NYS? As you can see, I'm just south of Utica. I'm the guy with the 20 cords of dry beech sitting in his backyard.

OK then.....never really took a close look at the EKO-60. man that's a huge boiler!

I'm in Goshen.

20 cords? Holy Moly! I only used about 6 cords this winter! I usually don't fire her up until the temp goes down below 40 degrees.

Don't split your logs too small.....I found she runs better on larger logs (6-8" diameter).

 

[webbie]

Here's the video I wrote, produced and star in about the Tarm Gasification boilers:

(broken link removed to http://video.google.com/videoplay?docid=110585530348764525&hl=en)

Have some laughs at the good lines in there! When I have time, I'll string the funny scenes together in a short version - until then, you have to watch the whole ten minutes:
(broken link removed to http://video.google.com/videoplay?docid=110585530348764525&hl=en)

 

[webbie]

Here's the southern equiv. of the Tarm Video:
(broken link removed to http://video.google.com/videoplay?docid=3005961029383795932&hl=en)

 

[begreen]

:lol: :lol: pure southern comfort

 

[Eric Johnson]

That's cute, Craig. You should check out the Adobe boiler video to the right of this one. It's pretty cool. I might run over to the plant when I'm up in Bangor for a look-see.

A couple of observations on your Tarm video:

1.) I think Grizzly Adams should have tossed that cigarette into the boiler instead of carefully putting back into his pocket. Or was that a joint?

2.) You took a completely gratuitous swipe at the logging industry--using fear tactics in a craven attempt to sell stoves. You mentioned a shortage of timber as an environmental reason to buy a Tarm boiler and thus burn less wood. I think burning less wood is a good idea for a number of reasons, but there's no shortage of low-grade timber in this country. On the contrary. What we should be doing is cutting more low-grade timber, creating healthier forests in the process and letting our better trees grow longer. Good markets for fuelwood, pulpwood and other low-grade products take the pressure off sawtimber, in other words.

A depressing number of people seem to equate wood burning with "murdering" trees and clearcutting. Statements like the one you made in the video serve to perpetuate misconceptions like that.

Other than that, I think it was a pretty informative video. Hard to argue with the disappearing smoke.

 

[webbie]

Yeah, I figured you'd pick that one up Eric!

Then again, on a worldwide basis it probably has some accuracy. Europe cut down 100% of it's forests for heat, cooking, building and charcoal. Logging is a BIG problem in many countries where virgin forests and rain forests and being removed - as the video says - "Far faster than they are growing".

Even in the USA we cut down the vast majority of the forests - for heat in inefficient fireplaces as well as building.

So, in the video, it's a quick way of saying that our natural resources all need to be used efficiently because there are so many of us and a relatively finite amount of them.

I'm not familiar with current numbers, but I assume we are still importing a lot of lumber from Canada, Europe, etc. which may also mean we are using more than is being grown here. It's a subject for a different thread, but it would be nice to know the actual numbers as far as lumber, paper, etc.

Of course, firewood is hardly even a blimp on the chart and today (in the USA) is not responsible for deforestation.

 

[Eric Johnson]

Everybody's got numbers to prove whatever case they're trying to make. However, it's a generally accepted fact that forest in America are growing at a much faster rate than they are being cut. That's been the trend for generations, as previously-cleared farmland reverts back into forest. Just drive the length of the Mass. Pike or the NYS Thruway and try to tell me we're running out of trees.

I agree with your point about deforestation in some parts of the world. That's what they get for following our example.

In this country, however, the problem is more a question of poor (or no) management, resulting in catastrophic wildfires, disease outbreaks and insect infestations, not overcutting as a rule. And the more forestland you either lock, up or neglect to manage, or watch burn, the more pressure it puts on the remaining acreage. Our appetite for wood grows, in other words, as we're actively taking more and more of it out of circulation.

Looking back to Europe, you only have to go as far as Scandinavia to see how to intelligently manage a forest for a wide variety of uses.

People forget: It's a renewable resource.