Fine Tuning BioMass

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Is the galvanized pipe the one coming from the boiler to the chimney ? On my system, I have a triple wall stove pipe, but couldn't find a triple walled tee fitting other than online and for way to much money, so I just bought a black stove tee. I wrapped some unfaced fiberglass insulation around it, and I think that really helped keep the temp up.[/quoyes the galvanized goes from boiler to chimney I have the insulated pipe with tee was going to put that on installer said I didn't need to use that so I think I'm going to put that on.
 
From Woodsmaster:

Do you have air adjustments for primary and secodary air? If so try opening the secondary air more and not just a tiny bit ,a lot.
I run my biomass almost a year before I figured out I didn’t have the secodary air open enough for my wood. I had trouble with
smoke sometimes and sometimes had trouble keeping gasifacation. I had tried adjusting the air before and adjusted a tiny bit at a time with no luck so I pretty much kept them where they were when I got it. One day I opened the secondary air up a lot and
havn’t had and trouble with smoke since. I do get some steam but no smoke. I also gained about 30 degrees on my stack temp due to the hotter fire. Somthing to try If you havn’t allready.
Hello I have a burnham oil furnce and it keeps shutting off I was wondering if you could help me
 
Mr Q, post your question on the general boiler discussion. You'll get a lot more help than here in the BioMass discussion.
 
Does anyone know the location of the temperature probe on the biomass 40? Is it easy to access?
All of your issues pretty much duplicate mine. For the circulation issue I used a 12 hour Intermatic timer with a bypass switch. This was wired into the hot lead to the fan. Actually the main reason I installed the timer was to be able to shut the boiler down with some unburned wood. Now I load it up, set the timer for about 6 hours and know that when I come back the boiler will be closed down and very easy to light up a new charge with the left over coals. If I want to override the timer, just leave it off and switch the bypass. It has made restarts almost painless.
 
Ok so my latest conundrum is I'm having a build up of creosote in the secondary tube (the single larger opening, the one just above the bottom door) . It is actually plugging up the whole tube, so it is not gasifying unless i unplug it. I don't know where the creosote would be seeping into it from. When I pull it out, its still all goopy, not crusty like what builds up on the door. It's a tar like consistency. A big tar plug.

Anyone else have this problem? Any ideas would be much appreciated. It just started happening, and I haven't really changed anything, which is what makes me curious.

My boiler has been burning great for about a month or more, and it has only just started doing this the past few days.... I'm burning 14-18% moisture hard woods. Fan is about 80%

Happy new year!
Eric O
 
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Make sure the nuts are tight on it. I thought mine was going bad, but it was just vibrating from being loose

Yeah it was tight. I took the fan off the other night, the vibration was from a lot of creosote build up. I'm thinking that my bypass flap must leak a little, because I don't know where else all the creosote would be coming from. My heat exchange tubes are clean....
 
Yeah it was tight. I took the fan off the other night, the vibration was from a lot of creosote build up. I'm thinking that my bypass flap must leak a little, because I don't know where else all the creosote would be coming from. My heat exchange tubes are clean....
I also get a tar plug in the secondary air inlet. There must be a passage way around the ceramic bricks a boiler steel that allows hot tar to flow down. It does harden up a bit and I open up the adjuster and use a flat screw driver and work the plug out. It actually cleans out quite easily. I haven't been able to solve the problem. I also have tar leaks coming out the primary ports. The steel sloped side plates butt up to the near side of the boiler end section and instead of being welded or very tight fitting I have a good 1/8" gap. So the tar flows through that and lays on the bottom of the secondary inlet passage.
Yeah it was tight. I took the fan off the other night, the vibration was from a lot of creosote build up. I'm thinking that my bypass flap must leak a little, because I don't know where else all the creosote would be coming from. My heat exchange tubes are clean....
I found that my bypass flap leaked and resulted in tar build up on top of the tube plate. I installed another plate on the inside of the boiler and clamped the two plates together with a bolt and now have no creosote. I found the bypass didn't work very well as a smoke bypass so I built my own smoke collection hood/fan just above the door and it works perfect. I don't need or miss the bypass damper. I have drawings etc. if you want. I also put an O ring and insulation to help make sure there was no air leaking by the tube cleaning shaft where it enters the boiler side plate.
 
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Ok so my latest conundrum is I'm having a build up of creosote in the secondary tube (the single larger opening, the one just above the bottom door) . It is actually plugging up the whole tube, so it is not gasifying unless i unplug it. I don't know where the creosote would be seeping into it from. When I pull it out, its still all goopy, not crusty like what builds up on the door. It's a tar like consistency. A big tar plug.

Anyone else have this problem? Any ideas would be much appreciated. It just started happening, and I haven't really changed anything, which is what makes me curious.

My boiler has been burning great for about a month or more, and it has only just started doing this the past few days.... I'm burning 14-18% moisture hard woods. Fan is about 80%

Happy new year!
Eric O
Yes I also get that plug. Hot tar must find a passage way to flow down around the ceramic bricks . It usually hardens as it flows out and I open up the adjusting plate and dig the plug out with a flat screwdriver. It actually is quick and easy. Haven't tried to solve the problem. I also get tar leaking out the primary holes. Where the steel slope side plates just above the firebricks join up to the door end of the boiler, it should either be welded or very tight. Instead I have minimum 1/8" gap and the hot tar coming down the side walls finds this crack and does it's thing. I have been working at plugging the crack by some other means than welding. I would take this issue as poor fabrication.
 
Yes I also get that plug. Hot tar must find a passage way to flow down around the ceramic bricks . It usually hardens as it flows out and I open up the adjusting plate and dig the plug out with a flat screwdriver. It actually is quick and easy. Haven't tried to solve the problem. I also get tar leaking out the primary holes. Where the steel slope side plates just above the firebricks join up to the door end of the boiler, it should either be welded or very tight. Instead I have minimum 1/8" gap and the hot tar coming down the side walls finds this crack and does it's thing. I have been working at plugging the crack by some other means than welding. I would take this issue as poor fabrication.

I've never had this happen yet.
 
Hope this goes through OK.
 

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Excellent job on the smoke hood bugwood. Id like to make one someday. I like to fix bridging and load mid burn and always get a bunch of smoke... One reason I went with the biomass is the induced draft, but it don't do much good pulling the smoke out.
 
Thank you Bugwood! That is one good looking hood. I plan on working on it this weekend.
I'm around so let me know if you have questions. I built a prototype out of lighter tin and 3/4 wood end pieces to make sure everything fit together a fit on to the boiler. For the final deal I stitch cut the bend lines with a zip disk, made the bends and then welded the cuts back up.
 
I think I'm just making up for a lack of natural draft from my chimney. I live on a hill with spurts of very windy conditions so I wanted to avoid going any higher with the chimney. Last year I had to open the upper door often to get a really strong burn, (starved for air?) Essentially trying to make a 60 out of my 40 with the aux fan.
Still have a steep learning curve to learn how to adapt to the changing conditions, (wood - barometric pressure - outside temp and now storage to keep charged.) Guess you could say we're having some fun now!
Interested in your learning curve. I have same equipment and on my second winter. I still have to leave the door partially open to get a good burn started and then it usually takes off, but not always. Has this extra fan taken care of that problem completely? (or close)
 
Interested in your learning curve. I have same equipment and on my second winter. I still have to leave the door partially open to get a good burn started and then it usually takes off, but not always. Has this extra fan taken care of that problem completely? (or close)

I have the same thing. I do get a gasifying flame, but sometimes it's not very strong... Have you guys ever had your refractory glowing as some people mention? I've never seen it get that hot yet....

Side question: So I've been struggling with lack of gasification actually. Many times, the wood either just smolders, or it will burn, but not down through the coals. ALso, there will be a big bed of "coals" but they wont be red hot. Instead the fire will be burning off on one side of the top chamber, but not heating up the coals near the nozzle...

IS there a possibility of having to thick of a coal bed? I just don't know if i should give it more air, or less....

Wood is 16-18% moisture, primary openings half open, secondary is open about 5/16 inch, fan is at 70% and front cover open 3/4 to 1 inch.
 
If you have to crack open the door, other than at start up, It's starving for air.
Edit : I have had my refractory glow, but not all the time. I don't even hardly ever look in the lower chamber anymore. If i hear it roaring and see the glow out the sight glass I know it's doing fine.

I leave the top door cracked at start up until flu gasses in the chimney get up to 325 F then I shut the door and 95% of the time its good to go. Usually only takes around 3 minutes unless I have less then dry wood or the nozzle gets plugged
 
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I have the same thing. I do get a gasifying flame, but sometimes it's not very strong... Have you guys ever had your refractory glowing as some people mention? I've never seen it get that hot yet....

Side question: So I've been struggling with lack of gasification actually. Many times, the wood either just smolders, or it will burn, but not down through the coals. ALso, there will be a big bed of "coals" but they wont be red hot. Instead the fire will be burning off on one side of the top chamber, but not heating up the coals near the nozzle...

IS there a possibility of having to thick of a coal bed? I just don't know if i should give it more air, or less....

Wood is 16-18% moisture, primary openings half open, secondary is open about 5/16 inch, fan is at 70% and front cover open 3/4 to 1 inch.
 
First of all I have primary air inlets at about 90% open, secondary air about 5/16 or so vertical opening (probably about 15% of area open). I leave the adjustable air gate on the front all the way open and run the fan a 90%. I'm burning 15% beetle kill pine.
It sounds like you are not getting secondary air to the nozzle. First you should be able to feel or hear the air entering at the inlet (with the middle access door open). Also, with no fire you should be able to feel the air inside at the nozzle air inlets. Once in awhile if I poker the bed of coals too much, the coals will plug the nozzle and will not allow air through and glassifying stop. This is evident by looking through the sight glass and see no flame. This can be cleared by poking from the lower door and push a bit of a hole up through the coals in the nozzle and that solves the problem. This doesn't happen very often, it's from careless stoking by the operator! If you are starting a fresh fire with fine wood and paper, there should be no reason for not getting a healthy roar in the nozzle and see a good flame thro the sight glass. With the top door cracked open your flame will be rich and look orange instead of yellow.
 
How do you guys clean the tubes? I did it last Saturday by removing the turbulators from the two pieces of flatbar. I had to make tools to do it and the process seemed far too painful for something that is standard maintenance. I'm embarrassed to say it's my first time doing this in 6 years. Huge difference in flue temps. So since I'll be doing this more frequently I'd like ideas. Removing the turbs as an assembly is out because the exit pipe goes straight back probably 8" above the top of the boiler. I operated this thing I think for 3 seasons before learning about cleaning out that top chamber. But I don't think this should have been an all day maintenance process.

BTW I made a very cool brush extension that I attached my cordless drill to. That part worked awesome. Just getting the turbs in and out was a nightmare.
 
How do you guys clean the tubes?

I leave the linkage unhooked. That handle don't do much in the way of cleaning... I then removed the cotter key on each end turb, leaving the middle ones hooked to the flatbar. this allows you to pull the middle ones out as one unit. On the end turbs I use a piece of metal rod to keep them from falling to the bottom. This makes it simple to pull the tubs out for cleaning. With storage you should only need to clean two or three times a year and just forget about that dumb handle on the side of the boiler. I would like to get some wing nuts to replace the nuts on the top, and lower side covers to speed up taking them off. Make sure to clean out the chamber under the turbs when done. I get a ton of ash in there.
 
Thanks everyone for the tips. I opened up the primary's more and it seems to be doing much better. Just wanted more air apparently.

So I haven't seen this come up in a while, but has anyone been using a grate over the nozzle to keep more of the coals from falling through? If so, is it wearing on the nozzle?
 
WM, I purchased a 3/8" drive for a cordless drill for a 10mm socket to remove the nuts. Probably faster than wing nuts to remove/install those 8 nuts on the top cover and the 4 lower ash removal panel nuts.

What linkage did you unhook? I strapped the handle in the up position so the turbs were held up as far as possible. From access thru the open top, I wasn't able to disconnect the levers at both ends with the holes the flat bar slips into. If I understand you somehow are able to pull the flat bars and the 4 middle turbs up out of the boiler at once. My exit pipe plumbing will not allow pulling the assembly up out of the tubes. I took all the turbs out at one time and in hindsight that was a mistake because I had to wrestle in that small space to slip the turbs back in between the bars. I had to make a wire tool to pick up the turbs and hold them as I wrestled to get them back between the flat bars. With my plumbing, it's not physically possible to pull out the flat bar assembly with the middle turbs installed. I also drilled holes in all my turbs below the holes for the pins so I could use my bent wire hook to pick turbs up from down in the boiler and pull the turbs up between the flat bar.

I think next time I remove the turbs I will be welding tabs onto the end so I have something sticking up to hold onto as I work to align the pins. I went to Tractor supply and bought small hitch pins to replace the cotter pins.

Sounds like the way my boiler is plumbed about the only change I'll do next time is not take all the turbs out at once so there's something to keep the flat bar spaced. I'm looking at my hands as I type and I have cuts and scrapes all over them from this job. Sure hope you're right about storage cutting this process to once a year. But I saw a dramatic drop in flue temp so it was worth it.
 
Since your plumbing is in the way maybe it would be easier for you to eliminate the flat bar altogether and just hang the turbs with a steel rods ? That handle on the side just don't do enough in my opinion to make it worth the hassle unhooking and hooking it up each time you clean it.
 
Yeah, I just may do that next time to skip the hassle of threading it thru those 2 bars. I was thinking of maybe going to something like a shackle. The shackle body thru the turb and pin thru the flat bar. I didn't unhook the handle when I removed the turbs. Also, as I took the pins out I just let the turb fall then after all off fished them up out with a 1/8" steel rod with bent hook on end. Only the two outside ones fall to the bottom of the ash chamber but still easy to fish up with my bent rod tool. I never disconnected anything to do with the handle, had it tied to stay in the full up position. Replacing the cotter pins with hitch pins will be a big help next time. Now just need to get smarter on how to reassemble the turbs.