Clarification on gasification boilers needed

[NE Properties]

Hi everyone,
I have been browsing this forum for a few days and would like some clarification if anyone can help.
I am in the process of looking for a gasification wood boiler. I really liked the EKO 60 which fits my needs perfectly.
I am confused though with the name change or sale of company? Is it now Paxo? They appear to be the same boiler. I did read somewhere that they are being built by a family member etc.
Without getting into the family politics etc, are either or both of these still being made? Are they and the parts readily available?
I have also been looking at some of the bio mass boilers and wonder how do they compare?
I would have liked to do this project now, but am rather uncomfortable with moving forward with this type of capital outlay without having this issue cleared up.
Any advice would be gratefully appreciated.
Thanks,
Pete
NE Ct.

 

[Eric Johnson]

I'm not sure what the situation is with the company that builds (or built) the EKO line, but you can still get a 60 from New Horizon Corp. The Biomass is a very similar design. Others are similar as well. They're all based on the same European downdraft technology. Some are simply knockoffs of other designs.

As to parts, yes, you can get parts from New Horizon as well. I just bought replacement nozzles for my EKO 60. That said, there are very few moving parts in these boilers and nothing that I can think of that can't be easily fabricated or cast or replaced with a comparable component. The controllers, for example, are the same on several different brands, and controllers from other brands and models will work as well. As my old friend nofossil likes to point out--these boilers appear to be very simple devices. The reason they work so well is all in the engineering.

I will give a plug for the EKO 60, even though there are some much more sophisticated units on the market today. It works and it works well. Does what it's supposed to do and does it well.

The main thing to keep in mind about these kind of gasifiers is that they require VERY DRY WOOD to work properly. My guess is that most of the problems people encounters can be traced back to inadequate fuel.

 

[NE Properties]

Thanks Eric,
I am starting to lean towards the BioMass 60kw. I like the idea of option of fuels and the larger firebox.
I am glad to hear that the EKOs and Paxo are still viable options. They sound like a good piece of equipment. Everything I have read so far seems positive. I have only gotten (1) negative comment from a dealer so far, and he was really ready to sell me something else.
Do these boilers work well without thermo storage? It seems to me that the more storage the better. I don't think they would cycle like an oil burner. My house is a 1730s Colonial (3,400 sqft.) and the dug cellar only has access through the house. I have yet to come up with a way to get a large tank or even several small tanks into the cellar. The cellar door being 28" wide and most of the cellar being part of the continental shelf makes for little room down there. I would like to put the boiler in this year and use it. Next year there is a barn going up and I can opt to put the tanks out there I guess.
I guess the question is do I go for it now and renovate the system next year or wait and do it all at once. If there isn't too much inefficiency with a system and no thermo storage, I would do it now. If there is a possibility of damage to the equipment or I end up just sending BTUs up the chimney then I guess I would have to wait. I can't see saving any money or heat with two tanks sitting out in the weather.

 

[Eric Johnson]

I don't have storage and it works well for me. I keep it going like a regular wood fired boiler, only it's a lot more efficient and a lot cleaner burning. When it idles, the temp stays at or near the set point (80 C in my case). So, really not a whole lot lost up the chimney. I think part of the reason I can get away without having storage is that I have a big, old 1865 2,800 sq. ft. Federal with lots of cast iron radiators, large diameter pipe and marginal-to-no insulation, double-hung windows--the works. So, I needs cheap fuel. As long as it's not way below zero, I can load it up before bed and still have a warm house and a boiler full of coals the next morning. We burn about 10 cords of nice, dry hardwood per winter, more or less. You can always add storage later; I don't see a huge downside after doing it this way for the past 8 years. One nice thing about no storage is that I rarely have to start a fire from scratch. I don't know the efficiency hit taken when you bring a cold boiler up to temp, but it's got to be something. Anyway, I've always planned to add 1,000 gallons of storage--just never got around to it, nor do I really see a need.

My general sense over the year that they've both been available is that people tend to be happier with the EKO than the Biomass. I don't have any details and it could just be my own prejudice, but I'd ask around if I were you.

 

[Fred61]

I don't know the efficiency hit taken when you bring a cold boiler up to temp, but it's got to be something.

I think there is a hit on efficiency but probably less than we realize. That cold boiler sucks a lot of heat out of those firetubes early in the fire. Rule of thumb ---- Work with lower temperatures for the highest efficiency.

 

[Eric Johnson]

I think there is a hit on efficiency but probably less than we realize. That cold boiler sucks a lot of heat out of those firetubes early in the fire. Rule of thumb ---- Work with lower temperatures for the highest efficiency.

That's interesting. Are you saying that it's more efficient to run your water temp (assuming you can get away with it) at 170 vs. say, 190?

Fred, are you still using the original controller, or have you "upgraded" to the newer model? Reason I ask is that while I have two of the newer models with blown capacitors sitting on a shelf in the basement, while the original unit is still controlling the boiler. I actually replaced the capacitors recently, so I'm thinking about giving the new one another whirl. More control options as I recall, including the ability to modulate the blower output down in really cold weather. But that all ended when the unit blew. Then, the warranty replacement blew. Back to the tried and true.

 

[maple1]

Next year there is a barn going up and I can opt to put the tanks out there I guess.

I like having everything in my basement - but if I had a basement like what it sounds like you have, and will be building a barn in the near future, I would start designing my barn now so it could hold my boiler, lots of storage, and my entire winters wood in one space. Sounds like a good opportunity for you.

 

[Fred61]

No, I don't follow my own rules. Just sayin that early on the cold boiler absorbs a lot of the heat. I'm still with the same controller (Ekoster 2) which tops out at 180 but I did some modifications. I buried the sensor up in the insulation which allows the boiler to reach about 195F. I transferred the responsibility of the circulator launch over to a Tekmar 156 with the source probe of the Tekmar placed under the clip where the Ekoster 2 controller had been. The Tekmar gives me the differential feature between the tank and the boiler. Only took two attempts to achieve the temperatures I wanted by moving the original probe. I did this all in my determination to achieve 180 degree storage. Having the old controller still gives me the fan speed adjustment feature as well as the out of fuel shutdown feature. It also acts as my on/off switch for my batch burn.

Yes, it is more efficient to run at 170 vs 190 but I can store more btus at the higher temperature. These tactics may or may not work for you as I have that big tank of water that forgives all the inconsistencies.

 

[maple1]

That's interesting. Are you saying that it's more efficient to run your water temp (assuming you can get away with it) at 170 vs. say, 190?

I was thinking that is what I was seeing last winter - and it seemed to get confirmed by others here. The cooler water around the fire tubes should draw more heat out of the gases before they exit the stack. It's only 20° - but, well, it is 20°. My first winter I was always driving my storage up in the 190 range, last winter I didn't push it past 175 or so. It seemed to take more wood to get that last 15° or so, relatively speaking. Since I added the Alpha load circ, I also run my storage down colder - it just runs longer than the 15-58 did with hotter temps, but still keeps the house warm.

 

[Fred61]

It's really expensive to absorb that last 15 degrees.

 

[NE Properties]

Next year there is a barn going up and I can opt to put the tanks out there I guess.

I like having everything in my basement - but if I had a basement like what it sounds like you have, and will be building a barn in the near future, I would start designing my barn now so it could hold my boiler, lots of storage, and my entire winters wood in one space. Sounds like a good opportunity for you.

Right now I have a small 1 car detached garage that holds my wood working and printing equipment. It's a disaster.
The plan is to add the barn next year with the equipment going up to the loft for work space and this building will become designated to wood storage and log splitter etc. I will probably put the water tanks in here. I am also looking at possibly building a unpressurized fiberglass/plywood tank in the cellar. I have access to fiberglass and resins and I could just assemble the entire thing in the cellar and drop heating coils etc into it.
I am leaning more towards the BioMass 60kw as it's range of operation facilitates running it now and still it will be big enough to handle the new building when it comes on line next winter. Plus the flexibility of burning different materials.
Like I said, I am just kicking ideas around. There seems to be MANY options here. I really appreciate this forum. I can't imagine doing this without the feedback of those of you that have already been there.
Of course the other problem is my OCD is kicking in to the point that by the time I cover and research all the options, it will be next year anyway!

 

[Eric Johnson]

I understand the appeal of unpressurized storage, but it's a lot more complicated than you might think. In my view (and limited experience), you'll save yourself lots of money and grief by going pressurized--specifically used propane tanks.

 

[NE Properties]

Thanks Eric. I probably will. There are several propane dealers in the area. I just have to contact them and see what they do with the old tanks. I know for safety reasons, they are retired long before their life expectancy. I don't know if there is a secondary market for them or if they are considered scrap metal after. I wouldn't be surprised if there is some liability issue with using them as a pressure vessel though.
Thanks,
Pete

 

[Eric Johnson]

I've never heard of a liability problem using old propane tanks. I mean, 15 psi with liquid is a lot safer than (whatever psi) with a gas. The main problem is that you need a whale of an expansion tank. I've thought about using a water heater tank, but a 160-gallon propane tank seems to be a popular option. You get it from the same place as the bigger tanks, so it's a one-stop shop.

 

[aeblank]

I have an hs tarm and they used to sell a collapsible kit. It was a ring with a huge bag in it.

 

[NateB]

I wouldn't throw out the idea of unpressurized storage. I don't think it is more complicated. It sounds like it would be a good fit in your basement, and your heat loss from the tank would be in your house not in a barn. Things to consider are, do you have access to someone who can weld your propane tanks to suit your installation, do you want to heat your domestic hot water with your boiler, would you ever want to use solar to heat your DHW in the summer? How will you protect your storage from freezing if something goes wrong? what is your current heating system? After you answer these questions. Look at the solutions on each type of storage. I found unpressurized more suited to my setup. I am by no means an expert. I am still setting mine up, but these were questions I have ask as I was buying all the parts.

 

[Eric Johnson]

I built an unpressurized tank out of an old cistern in my basement, lined it with rubber, built an elaborate copper heat exchanger and finally decided to scrap the whole project. My concerns were: Lack of confidence in the hx, which was fabbed out of copper pipe soldered together, lack of confidence in my tank's ability to hold 1,000 gallons of water without caving out, and lack of confidence in my ability to adequately seal off the lid. Other than those items, I thought it was a pretty good idea. Obviously, the problems were all of my own design (or lack thereof), but it all got me thinking that by the time you build the tank, buy or build an adequate heat exchanger, seal everything up and get it plumbed, it's probably a lot cheaper and easier to adapt a propane tank. There's a photo of the (two stage/reverse flow) heat exchanger around here somewhere. Most of it is intact and still sitting in my basement.

If I were going to go that route, I'd use a couple of big cast iron radiators for hx.

Here's what the hx looks like. I don't have the heart to scrap it.

 

[woodsmaster]

I have a biomass 60 and it works fine. Its about like the eko but has a couple upgrades. It has fines in the lower chamber to extract more heat and has a viewing window in the lower door. I think it was worth the 2 or 3 hundred more than the eko, but that's just my opinion as I've never had an eko. Storage adds much convenience but is not a must if you size the boiler to the heat load or a little smaller. Its the shoulder season and being over sized that gets you into trouble without storage. With storage I can do 1 fire every 2 or 3 days in the shoulder season with no idling or using another heat source. I even heat my domestic hot water in the summer and that just wouldn't work well without storage. It's nice to be able to sleep in in the morning or go away for a couple days and still have a warm house when you get up or come home. Also with storage you don't have creosote to clean out of the boiler or chimney. I haven't cleaned my chimney in three years and it still don't need it.

 

[NateB]

I would go with American solartechnics for tank and HX.

Eric was your cistern concrete? How did you keep the heat in it?

 

[Eric Johnson]

I never used it, but I built it with a layer of 3" foam board between the concrete walls and the rubber liner.

 

[jeffesonm]

I would put the whole thing, with at least some storage, out in the barn next year. Remember you will need to haul literally tons of firewood to this thing, 100+ lbs/day, and I would not want to do that up and down stairs through the house.

 

[Eric Johnson]

I also poured vermiculite into the part of the wall made of cinderblocks.

 

[Tennman]

Zenon will tell you that the BioMass was designed with the EKO as the design start point and adding features of second generation gasification boilers he saw emerging at the shows. I drove up to New Horizons with my mind made up to pick up a EKO 60 because of it's reliability history and many satisfied users here. Since this was our first boiler I was only interested in the EKO, BioMass, Attack price point. After comparing all of the boilers Zenon had on hand I decided to take a chance on the reliability of the BioMass. Glad I did. My biggest concern was hearing about some boiler designs rusting out. I figured everything else could be replaced or fixed, but if the case rotted out we'd be screwed. Now in the 6th season and finally running storage I'm seeing the full potential of our 60. Long story, but I basically had it so choked trying to extend burns for our mild climate and lack of storage, it never operated anywhere near it's potential. We're now seeing/hearing that afterburner flame and sound. For the price point, I'd make the exact same decision. Now with the knowledge that my wife and I enjoy heating with wood, I'd probably spend the money to go to the next level and get lambda control. Like all boilers, there are some folks who struggle getting it running correctly, but from following these individuals and the posts on the BioMass sticky, its almost 100% user error. To my knowledge the frustrated BioMass owners who sold their boilers, the new owners are now running them successfully. From my experience any BioMass negatives are most likely related to customer service. For many first time boiler operators spending several thousand more on a higher end boiler gets you a system from a supplier with enough margin to fund support. Without the guys here, including the many kind EKO owners, I may have also punted as a DIY'er gasification boiler installer/operator. Plan on storage, it transforms wood boiler operations. Best wishes. If you have specific BioMass questions feel free to PM me.

 

[Tennman]

Absolutely "Amen" to what Jeff said above about climbing stairs.

 

[Trex83]

...Now with the knowledge that my wife and I enjoy heating with wood, I'd probably spend the money to go to the next level and get lambda control. Like all boilers, there are some folks who struggle getting it running correctly, but from following these individuals and the posts on the BioMass sticky, its almost 100% user error. To my knowledge the frustrated BioMass owners who sold their boilers, the new owners are now running them successfully. ....

Side note to this, we are still running the same lambda probe on the MTX-L for my dad's setup. He's come to the same conclusion, he would have spent the 1k$ for the lambda control and the second temperature probe that goes in the water storage and the third sensor that goes in the flue to shut-off the boiler's pump.
I would give a call to your insurer, he might give you a heads up with what he's comfortable with or not. He may like better the barn to burn down than your house. You'll just have to ditch more money for insulated underground piping.

If you are not tight on cash and plan to live 10+ years where you are, buy a smaller FHG (40/50) and get more storage. If you want a less complicated system, get a biomass60 but spend 200$ to get the MTX-L oxygen sensor.

You wont have to read posts past midnight to understand why you don't have a nice flame down there or try to measure the air openings with a caliper in a dark basement...

Cheers,
Trex83