Boiler Advice

[rreihart]

As I've read through the forums I see most of the discussion pertains to stoves and fireplaces, but there are some who use wood burning boilers. I've been looking at, reading about, and researching wood boilers quite a bit. I really like the gasification types, like the EKO, but I'm having trouble convincing myself that they're worth the extra cost. From what I've seen they're about twice the cost of a standard wood boiler, maybe a little more. I have two issues that I'm looking for some advice on.

First, is the more efficient gasification boilers worth the extra cost? Does anyone have experience with both? How much less wood do you burn?

My other issue is the size of the boiler. I've been considering 140kbtu and 200kbtu units. Initially, I would be heating a house that requires about 90kbtu so both would be overkill. I would like to eventually have the ability to heat the basement and a separate building (about 150 feet away). What and how serious are the drawbacks to having too large a unit? Would you expect too much down time that would be smoldering and causing creosote? Would heat storage cancel out the drawbacks and make the larger unit a better option?

Any input would be appreciated. Thanks.

 

[Eric Johnson]

I'll have better answers to most of your questions in a few weeks when I get my new boiler going.

However, I can address a few of your concerns.

I think a standard, conventional wood-fired boiler runs around $4,000. I paid about $6,000 for my EKO 60 (delivered) from cozyheat.net. I think the current delivered price is $6,250.

They're supposed to burn about half the wood as a conventional unit (40% vs. 91% efficiency) and do it with little or no smoke. The convenience alone ought to be worth the extra cost, not to mention savings on the wood. I've used conventional wood boilers for about 12 years. This winter will be my first experience with a gasifier.

Gasifiers need very dry wood to work properly, however, so you need to have that onhand or you won't have much luck operating one. You can also burn dry corn cobs, wood pellets, shavings, etc. Anything solid and dry that was once alive, including soft coal.

Water storage is highly recommended with any gasifier, and if you oversize it, it becomes even more desirable. As I understand it, the EKO can idle alright, but it's better to run it at or near capacity and charge up your tank, than trying to supply heat from it on demand. As I understand it, the Tarm lacks a feature that the EKO has that allows it to idle indefinitely. The Tarm goes out eventually when there's no load. I'm not sure which approach is better, but with the EKO, you have the option of doing it either way.

According to the manufacturers, running without a storage tank is possible, but your wood consumption will be higher. I'm not sure exactly why this is, but that's what they say.

Ideally, if you have a big enough tank, you can fire the boiler up once a day and charge up the tank, then let the boiler go out and live off the stored heat. According to the manual, it takes about a half hour to fire up the EKO from a cold start, and you need to tend it until it gets going. Then it supposedly will burn clean for as long as there's some load on the boiler and you keep putting dry wood into it. Personally, I'm hoping to start it up once in the fall and never let it go out. That's basically how I ran my other boilers.

As to creosote, you shouldn't get any in the chimney or heat exchanger tubes under normal operating conditions, though you will always get some in the firebox, since the smoke being produced there contains creosote and some of it accumulates on the walls before it can be sucked down into the gasification chamber. They recommend scraping it out periodically.

 

[rreihart]

Eric, I hadn't heard anything on your install lately. I was wondering how that was going.

How often would you expect to load a standard boiler? From what I read, I would expect to load a gasifier twice a day?

I've looked at Harman boilers for right around $3000, that's where the twice as much comment comes from.

My concern about creosote during idle comes from a post I read here. I was having trouble finding it but finally did. It was in a thread started back in April and was posted by kc10ken. Should this be a concern since I would be idling a lot with a bigger unit, until I would add heat storage?

 

[Eric Johnson]

I've been out of town for a couple of weeks. I should have it hooked up the weekend after next. Carpniels is going to bring a pallet jack over, and hopefully we'll get 'er installed and pressured up.

I had a 70K btu Marathon boiler for about 10 years, heating an old 1,800 uninsulated farmhouse, and we burned about 10 cords of dry wood per year. I would say we filled it 4 or 5 times per day, though oftentimes you do more because you want a small, hot fire to keep the chimney relatively clean. But if you were able to jam it full of wood every time, then probably 3 times a day. I had a 150 K btu boiler heating about 3,000 square feet of pretty well insulated 150-year-old house, and we burned about 16-18 cords annually. Probably loaded it six or seven times a day, again, depending. That includes all domestic hot water in both cases.

I'm told that you jam gasifiers full of wood and go about your business, so two or three times a day sounds reasonable. Me, I'll be fooling around with it constantly.

I remember kc10ken's posts, too. I'm not sure what the problem was, but I suspect it's because he didn't have hot water storage and the thing was idling a lot. Everyone I've talked to since then tells me there's no creosote accumulation in the chimney or heat exchanger tubes, so I really don't know. One thing about ken's boiler that's different from the ones being sold now is that his didn't have the lever-activated heat exchanger cleaners. All the EKOs sold by New Horizon now have that as standard equipment, and it saves you having to clean them manually every couple of weeks. That's a dirty job, as he said.

You might want to check into New Horizon's new boiler line, the BioMax. It looks almost identical to the EKO line to me, but it's made by a different mfg. and has a fancy, curved firebox and gasification chamber. I don't know what the pricing is on that.

Anyway, hang in there for a couple of weeks and I'll give you a first-hand account of how it works--right out of the box.

 

[rreihart]

That's a lot of wood and a lot of loading, with a conventional boiler. So I guess a gasifier would have a distinct advantage in usage and loading frequency. I'm still a little stumped about the oversizing. I want to have the ability to cover additional future usage and I sort of like the idea of having a larger box that can maybe be filled less frequently. By going big I will be creating a lot of idling until I incorporate storage, which may not be until next year. I could have the same problem as ken.

I was at an expo a few weeks ago where NewHorizon was with a couple of distributors. They had the EKO and BioMax boilers there so I was able to check them both out. Pretty similar, but the BioMax had a few small things that seemed to improve on the EKO. The BioMax 60 is what I'm leaning toward right now.

 

[Eric Johnson]

I'll let you know about how a big boiler handles light loads. I have plenty of potential demand (big house, tank and a greenhouse), but I can bypass the tank and the greenhouse, so we can see how it handles a light load.

What kind of heating units do you have--cast iron radiators or baseboard or in-floor radiant? Also, do you plan to put the boiler in your house or in an outbuilding? How about domestic hot water?

What's the pricing difference between similarly sized EKOs and BioMaxes? Features?

 

[rreihart]

Boiler would go in the basement, beside a Buderus oil boiler (98kbtu). Domestic hot water is from a 30 gallon indirect. Main part of the house, about 1100 sq ft, has cast iron baseboard and an addition, about 700 sq ft, has infloor radiant. I almost bought a conventional wood boiler last fall when I was replacing the oil system but I ran out of time. Till I had put in a new oil boiler, re-did all the distribution piping, and installed the radiant in the addition, I had enough for a while.

I certainly don't need a 200kbtu boiler for my house, but I'm thinking about the possibility of supplying mom's house which is about 150-200 away. We would probably start using some of the basement if I could heat it without buying oil. I would also at some point in the future like to re-do the driveway and am intrigued with the thought of putting in a snowmelt system. That would be way down the road.

I'm pretty sure the EKO and BioMax are the same price from New Horizon. I talked to Zenon, the owner of New Horizon, at the expo and he showed me both models. Right now I can't think of the differences and its hard to find them on the website. There were I few things that pushed me toward the BioMax. Nothing huge, but a few things that sounded a little better. One thing the EKO has on its side is that its been around and its proven. I'm pretty sure the BioMax is new.

 

[Eric Johnson]

I probably wouldn't need the 200K either if I wasn't interested in heating the greenhouse. But since I can't afford to heat it with natural gas, I figured I'd go for the big rig and sink any excess heat into the greenhouse. I get free firewood and like to garden, so why not?

Looking at both the EKO and the BioMax in some detail, I think they're similar enough so that my experience with the EKO ought to give you a pretty good idea of how the BioMax would perform. They have the same controller and the basic design looks almost identical. If you can wait a few weeks, we should have some answers. I suspect the bigger boiler will be the logical choice in your case.

Zenon seems like a pretty good guy. "I am straight shooter," he says to me; "I don't screw around."

 

[rreihart]

Update on my boiler search. Last saturday I drove to WV and met Zenon of New Horizon. Wasn't exactly sure what I was hauling back, but determined to bring something home. Zenon was quit helpful in taking 3+ hours of his Saturday to show and explain a number of things and finally to load up a BioMax 60. The trip was going pretty smooth until I got home and had no good way of getting my 1500# baby to the earth. I'll try to attach a photo of the help that arrived the next day. A friend came out after church with his rollback. It may have been a little unconventional, but it worked.

I've managed to get the boiler into its new home in the basement and I've knocked a hole through the foundation block and chimney brick into an existing, currently unused flue. The flue has a 9" square SS liner in it, but I think I'm going to make a 6" diameter rigid liner and run it from top to bottom. There's an outlet from the first floor to the 9" liner, so I'd rather not take a chance on how well that's sealed or any other seems that I don't see.

Beyond the flue liner, I still have a lot to figure out with piping into the existing system and the associated controls. I definitely understand the need for hot water storage. I like the idea of using pressurized vessels so I've been searching some different outlets to see what I can come up with to use. Long way to go, but I have taken a step or two.

Thanks to those on the site for all the great info and feed back.

Rob

 

[kc10ken]

It's winter time again!

Just fired up my EKO 40 yesterday for the first time this season! Ahhhhh....the smell of gasifying wood!

YES...the gasification boiler is worth the extra cost!! What are the EKO 40's going for these days? I only paid $3000 for mine 3 years ago but I can imagine with the price of fuel being what it is the price is through the roof these days.

This year, since heating oil is around $3.00 a gallon here in NY, I anticipate saving at least $3000 this heating season.

As Jackie Gleason used to say....."How sweet it is"

 

[kc10ken]

Update on my boiler search. Last saturday I drove to WV and met Zenon of New Horizon. Wasn't exactly sure what I was hauling back, but determined to bring something home. Zenon was quit helpful in taking 3+ hours of his Saturday to show and explain a number of things and finally to load up a BioMax 60. The trip was going pretty smooth until I got home and had no good way of getting my 1500# baby to the earth. I'll try to attach a photo of the help that arrived the next day. A friend came out after church with his rollback. It may have been a little unconventional, but it worked.

I've managed to get the boiler into its new home in the basement and I've knocked a hole through the foundation block and chimney brick into an existing, currently unused flue. The flue has a 9" square SS liner in it, but I think I'm going to make a 6" diameter rigid liner and run it from top to bottom. There's an outlet from the first floor to the 9" liner, so I'd rather not take a chance on how well that's sealed or any other seems that I don't see.

Beyond the flue liner, I still have a lot to figure out with piping into the existing system and the associated controls. I definitely understand the need for hot water storage. I like the idea of using pressurized vessels so I've been searching some different outlets to see what I can come up with to use. Long way to go, but I have taken a step or two.

Thanks to those on the site for all the great info and feed back.

Rob

You'll find Zenon VERY helpful during the installation and afterwards. He walked us through every step until I had my EKO 40 up and running. Hat's off to him!