new wood hydronic boiler

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Wyoelkhunter

New Member
Dec 8, 2018
21
Western wyoming
hello,

Im new here but i am building a new house and have installed hydronics in my entire house in a slab on grade. The house is 2500sf of heated space and i would like to install a wood hydronic boiler but the research has proved daunting. I also own a sawmill so i have a never ending supply of wood scraps to burn so i would defiantly like to go with a wood fired boiler. Can you guys give me some guidance and list some boiler options?

I live in western Wyoming so we do get some pretty good cold spells. We had hydronics in our last house and loved them but they were run off an electric boiler. This one i want to go with a wood boiler for sure and i would also like it to be an indoor boiler. I have been doing hours of research online and i haven't found too many options, it seems like a lot of boiler companies are either out of business or the ones that are in business are crazy expensive. thanks for any help!
 
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Crazy expensive is a relative term. In order to make a EPA compliant wood boiler it needs storage and several firms will not guarantee a wood boiler installation without storage. Hard to beat a Froling from Tarm Biomass.
 
Explain "crazy expensive".
Anything from Tarm is good stuff and their customer service is excellent. Varmebaronen also looked very good when I was doing my research. As I was just finishing up my research and struggling on what to buy a used Tarm unit came up on this site and I bought it and installed it alongside with my local HVAC company who is also a Tarm reseller. My buddy who works for said HVAC company was rather well versed on the install and it works 100% seamless with my LP boiler.

FWIW the Varm guys spoke highly of the Tarm guys and my conversation with them was brutally honest. They pointed me away from some boilers with some good solid reasons.
 
Its confusing but HS Tarm is no longer imported and Tarm Biomass is now selling Frolings.
 
For an indoor wood boiler, the Eko units (linked here) are about as affordably priced as they come. They are gasification units and will require thermal storage. Without storage, forget it. Although they state the 25kW will heat up to 2500 square feet, I would recommend the 40kW unit for your home. The 40 has longer exchange tubes and a larger primary firebox which will make for a faster recharging of the storage tank.

Thermal storage tanks can be purchased, or like some members here have done, acquire decommissioned propane tank(s) and convert to your liking. The Eko line of boilers are very basic and built for the long run. An easier way to go would be with a Garn or Switzer model, they have storage built into the unit and are basically plug and play. The down side is the up front cost of those two manufacturers. They are built for the long run also.
 
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hello,

Im new here but i am building a new house and have installed hydronics in my entire house in a slab on grade. The house is 2500sf of heated space and i would like to install a wood hydronic boiler but the research has proved daunting. I also own a sawmill so i have a never ending supply of wood scraps to burn so i would defiantly like to go with a wood fired boiler. Can you guys give me some guidance and list some boiler options?

I live in western Wyoming so we do get some pretty good cold spells. We had hydronics in our last house and loved them but they were run off an electric boiler. This one i want to go with a wood boiler for sure and i would also like it to be an indoor boiler. I have been doing hours of research online and i haven't found too many options, it seems like a lot of boiler companies are either out of business or the ones that are in business are crazy expensive. thanks for any help!

How much are you expecting to spend?

Anything new you buy will also require dry wood.
 
Well i was hoping to be around the 7k range for a boiler. i priced out the smallest garn and i think they quoted me 13k which is a little more than i want to spend. the switzer sounds sweet too and i sent him an email about getting a price on one of those. eko sound nice, what do those tarm froling boilers run price wise? Also wondering where i am heating a slab on grade do i need as much thermal storage? i know in our old place the slab would radiate for days once up to temp. just wondering how to set this up most efficiently. thanks!
 
The storage allows the boiler to be run flat out for a couple of hours to charge up the storage. Once its warmed up then the boiler isnt run for a day or so. The storage has to be brought up quickly so heating a slab would not work.
 
When you say wood scraps, how small are these pieces? A bunch of small pieces in a gasification boiler don't work as they generate more smoke than what the unit can burn, creating a condition known as puffing!
 
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How much insulation under your slab?And no your slab cannot be classified as thermal storage.
If you have any plans of a workshop/workspace/garage,plan to put the unit there.
Mine is in a separate building,and i would never build again without the plan to put all fire sources in a separate building.
Pros,
-no chance of carbon monoxide poisoning
-no mess in the house,smoke,ash,bugs and dirt
-Warm workspace 24/7 all winter
-less chance of your house burning down.
Cons,
Havn't got any for you...others may but i don't have any.Even when i walk the 125ft at -40C i still know that i made the right decision.Besides who dosn't want a reason to get alone for a few minutes,or a valid excuse to leave the house when the wifes annoying friends come over.
 
thank you for the info, a lot of my scraps from the sawmill are as big a regular firewood splits and some are too big and still need to be split so the wood should work fine. I do plan on putting it in a separate building off of my garage and i also have a barn i could put it in but its about 80' away from the house but that is where the sawmill is at and my woodpile so that may make sense to put it out there. i do have a finished tool room in my barn that may work perfect.
 
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thank you for the info, a lot of my scraps from the sawmill are as big a regular firewood splits and some are too big and still need to be split so the wood should work fine. I do plan on putting it in a separate building off of my garage and i also have a barn i could put it in but its about 80' away from the house but that is where the sawmill is at and my woodpile so that may make sense to put it out there. i do have a finished tool room in my barn that may work perfect.

Your wood supply sounds good !
 
I've operated a wood gasification boiler (jetstream) with 1,290 gallons of storage for 36 years a boiler that could handle wet wood , but the output is so poor that it made no sense to burn wet wood .
The boiler I like on the market now is ether the Garn 1,500 or 2,000 boilers they have their own storage and are simplistic in design , operation ,maintenance . Although they seem expensive ,a comparable boilers in output and storage will end up costing just as much once you put boiler and storage package together .
This is a good video on a Garn setup .


If the Garn had of been around when I started I would have bought a Garn !
 
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I will share my story and hopefully it will be helpful. I live in cold central Maine. I started with an old used Tarm (not gasification) wood boiler with 820 gallons storage from American Solartechnics(Tom is great, you can check out the website or call him). I did this because I didn't want to afford the 10K or more for a new boiler. I was going to put the boiler and storage tank in another building and I am so glad I didn't. Even with the storage there is quite a bit of tending fire. After a few days of running the system I was happy not to have to walk out to another place. I did lose space in my shop but now it is toasty too. After a few years I found a lightly used Tarm Solo 30(gasification boiler) on CL for $1500, installed it and it is the Cat's Meow! On most cold days I run the boiler for 4 or 5 hours bringing the storage tank up to 170-185degrees and then coast thru the night. We have passive solar gain so on a sunny single digit day the floors are happy and not calling for heat and the house heats up with free solar power. Definitely need to close the shades at night though. Now I am researching the best back up system so I can go away for a week or so. The house is 1400 sq.ft. In the summer I fire up the boiler once a week for DHW. I got all the coils and tank from AmericanSolartechnics.
 
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When you say wood scraps, how small are these pieces? A bunch of small pieces in a gasification boiler don't work as they generate more smoke than what the unit can burn, creating a condition known as puffing!

a Lambda controlled (o2 sensor) boiler can help a lot with this, but even then there are limits. The Fröling S3 also has a "dry wood" setting that helps even more in this situation. For example burning lots of kiln dried cut-offs in a cabinet shop, etc.
 
My boiler is in the basement as well as my storage. The walls are partially insulated and the sills are sprayed with foam. The net result is that if heat does leak from the boiler or storage, it heats the basement and the floor above. I can normally run the boiler at night and charge up the tank to max and then after a half hour of so after the fire is out in the boiler I turn the system off and just run off the warm basement and the heat in the boiler that radiates out. In the AM I just turn the boiler on to supply the zones. If its real cold out I may leave it running t keep the zones on. I would have no interest in going outdoors to feed my boiler. I do have a bulkhead on my basement that used to be a Bilco type door until I replaced it with a full height "doghouse" with a standard door. I have a solid core door from the basement and the dog house is insulated. I just pull the stairs out in the fall and can load in a half a cord using wheelbarrow. If I stacked it I could get more but a lot more work. I just open the basement interior door and grab what I need and then load the boiler. I have never had insect issues. There is no heat in the doghouse so it stays around 45 degrees in cold weather. The only downside is if I add wood with ice on it, it takes several days to melt off

I don't keep much oil in my oil tanks btu wonder if they act as additional thermal storage. I have two tanks (550 gallons). If they were full that would be around 3850 pounds of oil. Its going to slowly heat up when the boiler is running and if the boiler is not running it will slowly give up the stored heat. If the temperature difference is 30 F that's over 110,000 btus

What I really need is low temp baseboards/radiant emitters so I can run my storage temps down farther. Hard to justify the cost as it doesn't cost me much except time to heat the house.
 
If I had to go outside to load my boiler or get my wood I wouldn't. No way, no how.
It was 0::F on Saturday and -2::F Sunday mornings when I restarted the boiler. I spent most of the weekend in the basement rewiring a couple of breaker panels in a tee shirt.
 
I will share my story and hopefully it will be helpful. I live in cold central Maine. I started with an old used Tarm (not gasification) wood boiler with 820 gallons storage from American Solartechnics(Tom is great, you can check out the website or call him). I did this because I didn't want to afford the 10K or more for a new boiler. I was going to put the boiler and storage tank in another building and I am so glad I didn't. Even with the storage there is quite a bit of tending fire. After a few days of running the system I was happy not to have to walk out to another place. I did lose space in my shop but now it is toasty too. After a few years I found a lightly used Tarm Solo 30(gasification boiler) on CL for $1500, installed it and it is the Cat's Meow! On most cold days I run the boiler for 4 or 5 hours bringing the storage tank up to 170-185degrees and then coast thru the night. We have passive solar gain so on a sunny single digit day the floors are happy and not calling for heat and the house heats up with free solar power. Definitely need to close the shades at night though. Now I am researching the best back up system so I can go away for a week or so. The house is 1400 sq.ft. In the summer I fire up the boiler once a week for DHW. I got all the coils and tank from AmericanSolartechnics.
What everybody dosn't get,or chooses to not remember is if your windows allow heat in"passive solar gain"
They also allow heat out "passive heat loss" at the same rate as they allow heat in.
I have Quad windows,and on a sunny summer day with the sun blasting through the window for hours i can lay a chocolate bar on the dark stone window sill and it will not melt.
 
What everybody dosn't get,or chooses to not remember is if your windows allow heat in"passive solar gain"
They also allow heat out "passive heat loss" at the same rate as they allow heat in.
I have Quad windows,and on a sunny summer day with the sun blasting through the window for hours i can lay a chocolate bar on the dark stone window sill and it will not melt.

Glass windows have all sorts of selective coatings that do different things in different areas of the country. In a sunny warm area of the country the coating may be "tuned" to reject UV and Infrared from the outdoors to reduce cooling loads while a coating system up north may be set up to let in the UV and infrared and keep if from leaving. I remember when these coatings came out folks didn't understand them and I remember a few folks calling them "plant killers" as UV screening screens out a lot of the frequencies plants want.
 
thank you for all of the info, i do like the idea of the boiler being inside, i have a loft above my garage and thats where the kids rooms are so it may be a good place for the water storage so at least the heat is not wasted it should heat up a little of the garage and help the upstairs temp stay a little more consistent.
 
anybody running a wood gun?

Yes, a few. Maybe one of them will catch this thread.

Have a friend who has had one for a few years now, seems happy with it.
 
There are guys with woodguns on here, muncybob will probably chime in.
My advise is if you go indoors, go with a suction draft unit or you'll be eating smoke if you reload mid-burn. It doesn't matter in an outdoor shed. Consider where you will store all the wood.
A big advantage to outdoor units is if set up right you can handle the wood only once.
If you're willing to shell out the cash and have the room, I like the simplicity and efficiency of the Garn design. Froling with tank(s) are another great but also pricey choice. If the economics are important to you, look closely at the return on investment. It takes a long time to recoup $20K.
Depending on your boiler, you don't "need" to have storage. If you want any efficiency you shouldn't be burning it when it's 50* out without storage. But you can just burn oil on the warmer days and for domestic water in summer.
Dry wood is number one - particularly to see the efficiency benefits of a gasification unit.
I suggest you plan on a backup source such as oil also. If you get injured and can't handle wood for months you need an alternative.
In the end, I couldn't justify a Garn and went with a lower $ EKO 60 9 yrs ago and I think it was the right move for me.
Be realistic about what you're trying to accomplish and good luck!