Fine Tuning BioMass

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Ok i did that and still not getting a huge flame, its heating house but flames then it smolders. Flames up when i open door.
Sounds as though it's starving for air or have a blockage on the exhaust side. Ok, you cleaned the heat exchanger tubes, did you clean out the base under the tubes (mine has small access panels on the side of the boiler, near the bottom toward the rear). Is your chimney clear? Does it have an elbow where fly ash or creosote might build up?
 
Yes i clean the tubes , cause i was having smoke leak from door. That stopped. I cleaned the base where tubes are. Chimney is clear. And exhaust pipe is clean well.
 
Just went down to tend to mine and it occured to me that perhaps your boiler is simply maxed out. With these gasifire units you don't have a roaring blaze in the upper chamber. If I fill mine I can lay a newspaper on top of the wood and if I open the door two hours later it will still be there; browned perhaps, but not burned. The idea is that basically the lower portions of the wood smolder, releasing the gas (smoke) which is then burned as it is forced through the "nozzles", the slot, or opening into the base. The burning of these gases is where the real heat is generated. Do you see orange or blue through the sight glass in the base? Will your boiler reach temp if the house loops aren't calling for heat or recover in a reasonable amount of time if the main circulator is off?
 
I dont think i have a sight glass, when house gets to temp it will go like in to a resting mode. And turn in and off as needed.
 
Sounds as though your boiler is doing the best it can do. Do you have any idea what the heat loss is for your house? A boiler the size of the 40, especially without storage, would be marginal for any more than a two bedroom cottage with average insulation. Boiler specifications are generally calculated under ideal conditions, with ideal fuel supply and boiler fine tuned to the max. You will seldom replicate that output under normal conditions. My 80 is rated at 300k BTU but I have a fairly elaborate distribution system that allows me to monitor real life output fairly accurately so I know that the 80 regularly cooks along at an average of just a bit over 200k with hard maple at 12%-15% moisture. Reality is that it is nowhere near big enough to handle the 280K load that would be demanded of it if we attempted to heat the entire house. We have 12 heating zones so we are able to dial down the heating requirements when it gets really cold.
Depending upon your distribution system and radiation your 100K boiler is probably not quite big enough. That said, if the house is warm don't sweat it.
 
Not sure of the heat loss in the house. I think im just wanting it to heat faster i guess. The heat is floor heat and it takes longer. Maybe im just being impatient. I appreciate all your help. Is that a Model M you have there. I have a 1950 Mt i restored.
 
It is an M. I bought it sight unseen about ten years ago; had been sitting out in a pasture for 30 years 200 miles south of here. Needless to say it needed a complete restoration. I did it over as a working tractor not a show piece and have used it ever since, primarily for raking hay and hauling wood from the deepest recesses of the woodlot where bigger tractors would be too cumbersome. I dismantled it and painted the parts before reassembly. Pics will give you some idea of the extent of the restoration. Pistons are the ones that came out of it (with difficulty, soaked them for 2 weeks and then it took an 8lb hammer to break them loose). Engine was a complete rebuild top to bottom but since cylinders don't have sleeves I used very coarse stones and honed them ten thousanths oversized; took forever :)
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A boiler the size of the 40, especially without storage, would be marginal for any more than a two bedroom cottage with average insulation.

I'm not sure about that. Mine is a 40kw rated boiler, and it heats a 2700 sq.ft. 25 year old 2 storey, on an open hilltop, burning only 6 hours a day. So it should be all kinds of capable, they can pump out the heat. Not having storage would play in for sure, but not sure it would be that much of an impact?

Other things that would impact, are low return temps (since floor heat was mentioned), and wood not fully seasoned.

Biomass40 - does your boiler have return temperature protection? If not it will make all kinds more creosote in the firebox than it otherwise should.

Also, in floor heat would take a while to heat up a space. It should be set up & operated more to maintain a space at a certain temperature, rather than heating it up. Are you raising & lowering temps? If not, then it would likely be colder outside temps pulling more heat away which might make it feel colder, which the in floor would be slower to react to. There are system design solutions to that, but they would be more complicated - requiring outdoor temp sensors tied to mixing valves.

Storage is the biggest game changer in this boiler business.
 
Biomass users what's the life expectancy on these things? I've been planning to work on a setup with a Vedolux v37 setup probably in my basement with 3 210-250 gallon tanks. I had a used Biomass 80 pop up online near me though. Would you touch one 9 years old on the used market? I can get it with 1000 gallons of storage (2x 500 gallon repurposed propane tanks) that's been in use since 2010. Outside looks good; inside looks like it has a fair amount of creosote on the upper chamber but maybe that's normal for them? Said it's been used about 2 months per year for heating a greenhouse so I'm sure it was run hard during that time period.

It would allow me to build a boiler shed next to the house for all the equipment instead of taking it into the basement through a 32" doorway. (up 3 steps to the house, through 2 rooms of hardwood floors and down a flight of stairs, 3 doorways and 2 degree turns involved). It may be a much more economical way to get going then in 5-7 years depending on how long those things should last if I want to go to a different boiler with more bells and whistles I could. I'm only 34 and plan on living here for a very long time so I've got time to get the life out of equipment.

//edit: when you referance pictures it helps to remember and post them :/

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Biomass users what's the life expectancy on these things? I've been planning to work on a setup with a Vedolux v37 setup probably in my basement with 3 210-250 gallon tanks. I had a used Biomass 80 pop up online near me though. Would you touch one 9 years old on the used market? I can get it with 1000 gallons of storage (2x 500 gallon repurposed propane tanks) that's been in use since 2010. Outside looks good; inside looks like it has a fair amount of creosote on the upper chamber but maybe that's normal for them? Said it's been used about 2 months per year for heating a greenhouse so I'm sure it was run hard during that time period.

It would allow me to build a boiler shed next to the house for all the equipment instead of taking it into the basement through a 32" doorway. (up 3 steps to the house, through 2 rooms of hardwood floors and down a flight of stairs, 3 doorways and 2 degree turns involved). It may be a much more economical way to get going then in 5-7 years depending on how long those things should last if I want to go to a different boiler with more bells and whistles I could. I'm only 34 and plan on living here for a very long time so I've got time to get the life out of equipment.

//edit: when you referance pictures it helps to remember and post them :/

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If the price was right, and it had been set up with return temp protection, I would certainly consider it. Any wood boiler without the return temp protection is prone to failure in the area where the return enters the jacket. My 80 is in its 6th year with no indications of giving up.
 
Can't get biomass 40 to reach temp its set at? Any udeas why this is happening?

Way late reply, dont look at this thread much.

Too cold return temps due to in floor heat and no boiler return temp.

That's a hunch. You didnt answer earlier on return temp protection. But accurately measure temp of your return water just before it enters the boiler.
 
Those settings worked alright for me. I found that the upper flame was smoldering and was having some undeniable smoke out the stack. I'm just in the second multi day stretch of consuming. So as of recently playing around with it, yet these settings appear to work with the pine wood I am at present utilizing.
 
I think actually the upper chamber is supposed to smolder, so to speak, with not a lot of flame. But that smoke the upper chamber makes, is supposed to get turned into really hot fire in the lower chamber.
 
Hi all. First of all, thank you for this fantastic resource and everyone's input!

After doing a ton of reading here, I installed a Biomass combo 40 with 500 gal storage last month. So far, it has met every expectation and seems to be running great. I don't have the oil hooked up yet, only plan to use that if i am on vacation anyway. I'll get a round-to-it. :) 3000 sf house with so so insulation and standard baseboard radiators. Relined the chimney with a 6" SS liner and poured in insulation. That including breaking out the old tile liner. It's been quite the DIY project, not for the faint of heart!

We've been heating with wood for years and replaced a relic from the 70's that was basically a short barrel turned sideways with a water jacket, no storage. That supplemented a standard oil boiler, though we only used 75 gallons of oil per year on the coldest of days. I used to just run the oil alone and it would not be uncommon to use 1200-1500 gallons in a season. The old wood burner had a voracious appetite! I think we are using between 1/3 and 1/2 the wood we did before while keeping the house warmer and only burning 5 hours per day this time of year.

I do have a couple questions from this thread. Someone mentioned trying a steel plate on top of the nozzle to help protect it from erosion. Did that help? I can see some rounding of the corners already on mine.

Any report from the Oxygen sensor in the flue idea?

I am also interested in a flue temp setup, but not impressed with the cheap looking sheet metal gauges. Anyone have some ideas on a digital setup?

I can already see I would like to have more storage and also want to install some sort of domestic hot water heat exchanger. Upgrades for next season most likely.
 
Hi all. First of all, thank you for this fantastic resource and everyone's input!

After doing a ton of reading here, I installed a Biomass combo 40 with 500 gal storage last month. So far, it has met every expectation and seems to be running great. I don't have the oil hooked up yet, only plan to use that if i am on vacation anyway. I'll get a round-to-it. :) 3000 sf house with so so insulation and standard baseboard radiators. Relined the chimney with a 6" SS liner and poured in insulation. That including breaking out the old tile liner. It's been quite the DIY project, not for the faint of heart!

We've been heating with wood for years and replaced a relic from the 70's that was basically a short barrel turned sideways with a water jacket, no storage. That supplemented a standard oil boiler, though we only used 75 gallons of oil per year on the coldest of days. I used to just run the oil alone and it would not be uncommon to use 1200-1500 gallons in a season. The old wood burner had a voracious appetite! I think we are using between 1/3 and 1/2 the wood we did before while keeping the house warmer and only burning 5 hours per day this time of year.

I do have a couple questions from this thread. Someone mentioned trying a steel plate on top of the nozzle to help protect it from erosion. Did that help? I can see some rounding of the corners already on mine.

Any report from the Oxygen sensor in the flue idea?

I am also interested in a flue temp setup, but not impressed with the cheap looking sheet metal gauges. Anyone have some ideas on a digital setup?

I can already see I would like to have more storage and also want to install some sort of domestic hot water heat exchanger. Upgrades for next season most likely.
Not certain how a steel plate would work but I tried a piece of a cast iron grate over mine one year. It might have helped extend the life of the nozzles but was a PITA and was so deformed from the intense heat that I removed it after a couple of months. There is a very good reason that the base of the upper chamber is ceramic. Not sure what other's experience has been but I have found that the nozzles seem to last 3-4 years.
 
Best thing to do for a biomass nozzle is to get a few firebricks and make an “overlay”.

I’m going on ten years on the original nozzle with the fire bricks. Probably time to replace the fire bricks but the nozzle itself is fine.
 
How are the firebricks held in place? Confused as to how they would be arranged.

I am still extremely happy with this boiler. Burning typically for 5-6 hours in the evening to get the storage up to 175-180 and we're good until the next day. If it's real cold (single digits) I need to burn for a few hours in the morning too. Counting my blessings especially after reading the sad saga about the Vapor Fire on the forum.
 
I think it took 6, maybe 8 bricks for my biomass 60. The 4 in the center need to be cut. I used a tile saw but a grinder with a diamond blade would work. They just sit on top of the nozzle. I spread some sand around to lock them in place.

The first pic is how the nozzle looked after the first year. More erosion then I would have liked. Get the “splits” when you buy firebrick. They are only 2” thick and fit quite well without taking up much space. I don’t think I had to make any changes to the air settings.


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I think it took 6, maybe 8 bricks for my biomass 60. The 4 in the center need to be cut. I used a tile saw but a grinder with a diamond blade would work. They just sit on top of the nozzle. I spread some sand around to lock them in place.

The first pic is how the nozzle looked after the first year. More erosion then I would have liked. Get the “splits” when you buy firebrick. They are only 2” thick and fit quite well without taking up much space. I don’t think I had to make any changes to the air settings.

Brilliant solution Mike, with a few days warm weather on tap I may do the same with my 80!
 
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