Gasification boilers

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Quincy

Member
Sep 26, 2012
30
Ontario
Happy Holidays everyone just a question for Those folks using a gasification wood boiler . What is the realistic burn time of a boiler such as a froling or tarm ? How many degrees would it drive up a 1000 gallons of storage in one load ? Thanks
 
I think 3-4 hrs is typical of most gassers. Output depends on boiler rating (firebox size). Could do some math on that and get close on temp rise of 1000 gallons.
 
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What size boiler? There are some buffer tank sizers online, this one from Lochinvar.

I used 1 55,000 BTU/ hr input, with one small 10,000 load calling while the tank was charging.

Usually if it is a cold, near design day you will have some heat load at the same time you are trying to charge up the tank, so you need to put some more numbers to the question.

The load of the building in BTU/ hr, the actual output of the boiler would be needed to get a close answer.

A 40 KW boiler running at 80% efficiency would have an output around 109,000 BTU/hr. If you keep it fueled up and running at full capacity.
 

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Was thinking about this on the way to Xmas eve service. And while there too actually, tsk tsk. My quick ballparking round number mind games came up with 50 degree temp rise for 1000 gallons for 120kbtu boiler at 80% efficiency on a really full load.
 
Thanks for the replies. It's funny where our minds go when we have idle time such as Xmas service. I was doing the same thing. Those are some pretty impressive real life numbers. A 50 degree temp rise is very impressive on a single load. I know there are a lot of variables but it's nice to see some real numbers before committing to a true gasification wood boiler. I've been struggling along with an approximately 60,000 btu home built seton and 1000 gallons of storage for years now. The boiler works good but the constant tending every hour or two to drive the tank temp up is getting old. So with a 50 degree temp rise are you guys only firing once a day or twice a day? Do you get much heat coming directly from the boiler? My boiler and tank sit in a separate out building approx. 700 sq ft which I like to keep heated from just the boiler heat loss itself.
 
Quincy, I have a home built Seton 130 with 500 gallons of storage (pressurized) and it takes me about 2 hours to go from about 150F to 190F. When its really cold ( like now, 3F ) I will fire it up 3X a day: morning, mid afternoon and about 10PM. When its mild outside , say mid 20's or warmer, just a morning and early evening fill is all I need.

I always have some hot coals I stir up to re-ignite the next burn, so I rarely have to light a new fire. I doubt if I could get a 50 degree rise on a single load with 1,000 gallons, but with 500 gallons it would be easy. It seems a little odd that you have to fire up that often, even though you only have a 60K BTU boiler. I would have thought maybe only 1 additional loading to get up to temp?

Pat
 
I've been heating up 600 gallons for a dead cold start place used weekends for now and it's 3 loads with a load at LP-wood changeover then 1.5/2.0 loads a day but that was in single digits and below 2 weeks ago. House was very toasty and the basement was almost 80.
 
It is nice to have a storage calculator, but there are some other parameters I would suggest considering.
First is what is the minimum storage temperature that you want the tank to go to.
That is based on the minimum heat distribution temps. For example, a radiant slab could be functional with 100F water while most
HWBB would not work below 140F. Are you taking DHW from that tank? Then under 120F is trouble.

Second would be how long are you considering in between firing? This is simple arithmetic. A gallon of water raised one degree F, holds 8.32 btus.

All something to calculate once the holiday is over.

Merry Christmas and a Warm New Year!
 
Merry Christmas Quincy. One load, not jam packed in my Tarm Solo Innova 50, brings a 1000 gallons of storage from 140::F to 180::F, while simultaneously heating the home during the burn. Never really timed it, maybe three hours, more or less.

Mike
 
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Merry Christmas Quincy. One load, not jam packed, in my Tarm Solo Innova 50 brings a 1000 gallons of storage from 140::F to 180::F, while heating the home during the burn. Never really timed it, maybe three hours, more or less.

Mike

Very similiar results with my Effecta...when I had it. A load of wood was about 100#
 
Thanks guys for all the replies . I realize now ,my wood boiler is taking far to much effort and tending to be an enjoyable chore.Seeing the time and ease you guys bring your storage up to temperature has me convinced a true gasification boiler is a must. Huffdawg you have really brought your wood burning to a new level of sophistication . That is some great data logging your doing and very helpful Thankyou well done. Can you answer a question what is the reason for the buffer tank as well as storage? I remember when you switched from an EKO to the froling I would imagine it was a significant change for the better. Pat when I built my boiler I made the heat exchanger to small it's only about 16 " wide double row of water tubes. I should have made it wider but was limited by the existing size of the steel casing which was already assembled . I pretty much light a fire in October and keep it burning all winter. Much abliged Quincy.
 
My schedule has been off for quite a few days now and yesterday it finally caught up to me, I had to do two burns. Think I can count on one hand how many times I've had to do that and the current cold snap finally crossed with my off-schedule. Hope that got me back to once-a-day latter day lighting up. Storage is down to 144 right now but the sun is coming up and I'm the only one here so I should be able to delay burning until this afternoon. Even though it is -20c outside. It has been many many years since it has been this cold here this early for this long.
 
Thanks guys for all the replies . I realize now ,my wood boiler is taking far to much effort and tending to be an enjoyable chore.Seeing the time and ease you guys bring your storage up to temperature has me convinced a true gasification boiler is a must. Huffdawg you have really brought your wood burning to a new level of sophistication . That is some great data logging your doing and very helpful Thankyou well done. Can you answer a question what is the reason for the buffer tank as well as storage? I remember when you switched from an EKO to the froling I would imagine it was a significant change for the better. Pat when I built my boiler I made the heat exchanger to small it's only about 16 " wide double row of water tubes. I should have made it wider but was limited by the existing size of the steel casing which was already assembled . I pretty much light a fire in October and keep it burning all winter. Much abliged Quincy.

Quincy , I prolly wouldn't have piped it with a buffer tank if I had planned on having a boiler room on the back of my shop when I built it. The main reasons were it made an easy to plumb to manifold and the 2 -500 gal. storage tanks were located in a separate space about 25' of piping away.Having said that it all ended up working quite well for me anyway. It also adds 150 gals capacity and it seems to work well having the top of the buffer as the high point in the near boiler piping with a vent on top and a connection to the expansion tanks which are located below.Having the Vesta controller made it a lot easier to