Wood boiler recommendation for heating shop and farmhouse?

[Vtheavytimber]

Hello,
I have a shop that is 2800 sf, with 14' ceilings and is pretty well insulated. I plan to enlarge the shop to 3325 sf, as well as add a single story office of about 500 sf. I also have a 1750 sf old, poorly insulated farmhouse that I'd like to heat. The shop will have a radiant floor, and the farmhouse would be heated with radiators. I'm in Vt, so any boiler needs to be EPA rated to step 2 certification, I believe. I'd love to get a Switzer boiler, but I don't think that they have the rating. As a timber framing shop with a sawmill, we have all the wood we could ever need. I think we'll solely be using the boiler for heat, as I don't want to have to fire it in the summer for domestic hot water. I would love if you could give me any recommendations for boilers, or things that I should be thunking about. Thank you!!

 

[peakbagger]

Vermont does not like Outdoor wood boilers. Here is link to review https://dec.vermont.gov/air-quality/compliance/owb/vt-certified-outdoor-wood-boilers

Ideally you want a combination of large thermal storage tank and an indoor wood boiler. The problem is heat demand varies while a boiler is most efficient when running steady state. If there is no storage and the heat demand drops, the boiler has to "slow" down. It not very practical to reach in and take wood out so the only way to reduce load is reduce the amount of combustion air introduced. This can very rapidly change a clean burning boiler into a dirty one.

This free course may be of interest https://www.heatspring.com/courses/hydronics-for-high-efficiency-biomass-boilers

 

[Vtheavytimber]

Thank you! I certainly don't want a smoky outdoor wood boiler, I'm not a fan and my neighbors would quickly come to hate me. As I read the regulations, I'd need to get a boiler that is EPA certified to "step 2", as shown here: https://dec.vermont.gov/air-quality/compliance/owb/new-wood-heater-boiler-regulations. Gary Switzer has recommended I have 1400+ gallons of storage, and I believe that I'd be able to use the radiant floor in the shop as a form of "storage".

 

[salecker]

Plan on storage tanks.
The floor will not be usable for storage. Any heat loss from storage will heat your shop or house depending where you place it.
I used propane tanks for my system.
Make sure you research underground lines before you buy any, as bad ones will rob you of BTU's
You will want to insulate under your slab if it isn't poured already

 

[Tonty]

Yes, if you want to do the system right, you will need storage and like @salecker said, don’t plan on floor pipes as storage. Sounds like you’ve talked to Gary, he makes a great boiler and it would suit you to the T, but you’re right, it isn’t EPA certified. Some of the Polar models are EPA certified and they are good boilers, I believe. I don’t know if they are Phase 2 certified or not.

 

[PassionForFire&Water]

Currently Certified Mid-Size Wood Heating Equipment for VT
There is a 369,000 BTU/hr wood chip boiler on the approved list

• Currently Certified Mid-Size Wood Heating Equipment

https://view.officeapps.live.com/op/view.aspx?src=https%3A%2F%2Fdec.vermont.gov%2Fsites%2Fdec%2Ffiles%2Faqc%2Fcompliance%2Fdocuments%2FApproved%2520Mid-Size%2520Wood%2520Heater%2520Certifications.xlsx&wdOrigin=BROWSELINK

 

[Vtheavytimber]

Yes, if you want to do the system right, you will need storage and like @salecker said, don’t plan on floor pipes as storage. Sounds like you’ve talked to Gary, he makes a great boiler and it would suit you to the T, but you’re right, it isn’t EPA certified. Some of the Polar models are EPA certified and they are good boilers, I believe. I don’t know if they are Phase 2 certified or not.

Thanks. The other boiler I'm looking at is the Froling S3 turbo 50. I need a cordwood boiler as we make plenty of wood "waste" that will work very well for a boiler.

 

[brenndatomu]

Thank you! I certainly don't want a smoky outdoor wood boiler, I'm not a fan and my neighbors would quickly come to hate me. As I read the regulations, I'd need to get a boiler that is EPA certified to "step 2", as shown here: https://dec.vermont.gov/air-quality/compliance/owb/new-wood-heater-boiler-regulations. Gary Switzer has recommended I have 1400+ gallons of storage, and I believe that I'd be able to use the radiant floor in the shop as a form of "storage".

Look at HeatMaster G series...EPA certified, basically smokeless...and no extra storage needed. You would probably be fine with a G4000 in my opinion, the G7000 would work, but they like to be run hard, so I'd lean toward the smaller one...dad put in a G10000 and its overkill for 2 farmhouses and 2 shops, one of them pretty large...a G7000 would have done the job 99% of the time, and they have backup heat, so...

G Series | Wood Burning Furnace Heaters | HeatMasterSS

The HeatMasterSS G Series is widely recognized as THE outdoor furnace of the industry. See why customers choose this wood burning furnace!

heatmasterss.com

 

[salecker]

You may want to see where @ Take no prisoners thread goes first...
Although almost all brands of boilers have a leak thread on Hearth

 

[cumminstinkerer]

yES THE

Yes, if you want to do the system right, you will need storage and like @salecker said, don’t plan on floor pipes as storage. Sounds like you’ve talked to Gary, he makes a great boiler and it would suit you to the T, but you’re right, it isn’t EPA certified. Some of the Polar models are EPA certified and they are good boilers, I believe. I don’t know if they are Phase 2 certified or not?

Yes, the polars are Phase 2 compliant, and are built like tanks, I have been running mine now for I a bit over two years and love it, have had a couple gaskets leak air but no other issues, load it and forget it! I am running a G2+ with 1500 gallons of insulated storage

 

[peakbagger]

Someone has a complete system for sale on craigslist in Ogunquit Maine, A Tarm Solo 40,a 1000 gallon stainless storage tank and three heat exchangers. 15K

 

[oaksplitter]

I have been very happy with my Froling S3 Turbo 30 with 820 gallons of storage for my farmhouse. I would definitely recommend the older cast iron radiators or modern fan driven convectors for heating the addition you mention. Both work better at lower water temps which will get you more out of your storage. The in floor will do fine. The folks at TARM were great help for my DIY install

 

[SRSTUDIO]

Hi,

I am new to this forum so please apologize if this is not the appropriate thread. I am building my woodshop, 1800 sqft, steel structure with R-19 insulation walls and roof. Only 4 windows and insulated rollgate and 1 insulated personnel door on 4" slab. We are laying the pex for hydronic radiant system. I am trying to figure out the most efficient heat source. I live on the MAINE coast outside PORTLAND, so we are a but high to rely on PV panels exclusively, but I have considered doing a system with 6, 4x8 panels and a 15KW electro industries boiler as a backup. I doubt I will get much solar as I hear on a good day maybe I can get 18000 btus and my draw is likely 50,000 btus on coldest days.
I wanted to do a wood boiler and found 92% efficient MBTEK which i really like but then comes all the labor etc. CAN ANYONE PROVIDE FEEDBACK ON BEST WAY TO HEAT WATER FOR A RADIANT HYRDONIC SYSTEM?

 

[hyfire]

Do not buy an MBtek customer service is poor and if you want smoke this the boiler to use. They are up draft boilers so each load the wood must ignite 1st producing smoke. Then each time you add wood it smokes again. The burn times are not accurate, you be lucky to get 2 hours out of it in real life. If you choke it down on a full load to get a longer burn it will just smoke. Spend the money on a gasifier.

 

[peakbagger]

Hi,

I am new to this forum so please apologize if this is not the appropriate thread. I am building my woodshop, 1800 sqft, steel structure with R-19 insulation walls and roof. Only 4 windows and insulated rollgate and 1 insulated personnel door on 4" slab. We are laying the pex for hydronic radiant system. I am trying to figure out the most efficient heat source. I live on the MAINE coast outside PORTLAND, so we are a but high to rely on PV panels exclusively, but I have considered doing a system with 6, 4x8 panels and a 15KW electro industries boiler as a backup. I doubt I will get much solar as I hear on a good day maybe I can get 18000 btus and my draw is likely 50,000 btus on coldest days.
I wanted to do a wood boiler and found 92% efficient MBTEK which i really like but then comes all the labor etc. CAN ANYONE PROVIDE FEEDBACK ON BEST WAY TO HEAT WATER FOR A RADIANT HYRDONIC SYSTEM?

The wood boiler is actually just one component of much larger system. To start with the best heating system is designed to run with the lowest temperature water. Hydronic is quite good at that as there are no ducts to deal with but you need to go with low temperature radiant emitters, typically european designs, or go with walls floors and even ceilings with radiant tubing and proper heat reflectors inside them. Standard slant fin style baseboard was designed to take up space and be supplied 160 to 180 F hot water from an oil boiler. Ideally you want a heating system that can heat the space with 90 deg F water via radiant heat transfer. That means a lot more surface area of heating. If its new space, there is lot to be said for a very well insulated slab with radiant tubing poured into it. The problem is most folks go cheap on insulating slabs and once they are poured the insulation cannot be upgraded as its under the slab. Most slabs in Maine are woefully under insulated if at all and insulation around the edges of slabs seem to be dark art that few care to master.

The next component is thermal storage. A wood boiler wants to burn hot at full capacity, there will be some "turn down" on a boiler but its not wide of a range. So the best wood boiler burns full bore to charge up a thermal storage to high temp and then the boiler is allowed to go out. The building space is heated from the thermal storage plus heat radiating off the wood boiler during an after operation (assuming its inside the heated space).

Unless you want a new boiler, there are frequently good deals on craigslist. Heating a boiler with wood is more complex and has more labor than flipping a switch and it takes the right person and attitude to do so. When the are no longer able or interested or a house is being sold, these systems on occasion get sold with plenty of life left on them. I would not worry about slight differences in boiler efficiency for modern wood boilers, the methods used to the test tend to vary between brands and the configuration of the system can change the overall system efficiency.

If you go with new equipment plan on $15 to $20K for the boiler, storage tank, circulators and basic controls