Homemade and Engineered Gasification Boiler

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Very nice. Where in the combustion chamber are you measuring temperature? I tried measuring in the actual flame zone, but it was way to hot. My thermocouple maxed out at 2500, and it was hotter than that. I now measure 'around the corner' - out of the direct flame and nect to the water jacket, but before the HX tubes. Mine are only 18" :-(
 
Very nice. Where in the combustion chamber are you measuring temperature? I tried measuring in the actual flame zone, but it was way to hot. My thermocouple maxed out at 2500, and it was hotter than that. I now measure 'around the corner' - out of the direct flame and nect to the water jacket, but before the HX tubes. Mine are only 18" :-(
Measure the secondary right under the heat exchanger, about 18" from the nozzle it usually gets to another 1500F. I was just curious on what it was getting right under the nozzle and yeah my meter pegged out at 2000F couple good until 2200F. When I have long run times like for me is 40 minutes ( I have no storage) the fire brick and ash deposits appear white which looks pretty hot to me! I do a little blacksmithing and the secondary chamber works pretty good to get the steel cherry red:)
 
Measure the secondary right under the heat exchanger, about 18" from the nozzle it usually gets to another 1500F. I was just curious on what it was getting right under the nozzle and yeah my meter pegged out at 2000F couple good until 2200F. When I have long run times like for me is 40 minutes ( I have no storage) the fire brick and ash deposits appear white which looks pretty hot to me! I do a little blacksmithing and the secondary chamber works pretty good to get the steel cherry red:)
I'm new to the site but I'm pondering building a gasser, I'm currently running a homemade conventional boiler that I'm gonna mod for now and run a couple more years while I'm working out the gasser. my first mod to my current boiler is to add a firebrick baffle and secondary air, I would sure like your input on my plans. not sure if you can pm on here but if you can please do Thanks
 
The cold water fuel chamber is on purpose in most gasifiers to slow down pyrolysis. With insulation, the temperature in the fuel box is more variable therefore the rate of gasification is more variable. This means more messing with primary and secondary air to get it tuned.

Also making most of the chamber cold for the same size gasification rate overall means a smaller, hotter zone of gasification and less tars/long chain smoke is made which means you don't need as long of dwell time in a tunnel to break those back down and completely burn them.

I did not like 170F water around the fire box because to me it is like burning a fire inside of an ice box. To get temps correct in my opinion the fire box should be over 500F and be easily maintained for pyrolysis to occur.
 
I would imagine this is why they want water jacketed gasser to run flat out high fire until they are out of wood. If it would sit idle too long the heat would be gone from the primary chamber and then it would take to long to get up to temps without secondary flame.

I needed to be able to run at least 12 hours and I did not want to be restarting a fire all the time. I usually start a fire 2 -3 times a season and I have been loading every 13 hours. My unit does idle a lot but always has a small pilot from the idling gasses still gassing off from the wood in the secondary chamber. The disadvantage to my setup is I loss heat to the garage I have the gasser in, so it is always heated even when I don't need it to 70F all the time. So I burn more wood than a jacketed gasser but I can live with that. I thought about adding storage but I don't really see the benefit in my situation (yet)



The cold water fuel chamber is on purpose in most gasifiers to slow down pyrolysis. With insulation, the temperature in the fuel box is more variable therefore the rate of gasification is more variable. This means more messing with primary and secondary air to get it tuned.




Also making most of the chamber cold for the same size gasification rate overall means a smaller, hotter zone of gasification and less tars/long chain smoke is made which means you don't need as long of dwell time in a tunnel to break those back down and completely burn them.[/QUOT).[/
 
Another corny video of my gasifier, I apologize I am not the best video/talker! I just loaded with half pallets and split wood.
 
what did you do to meter your primary/secondary air? and I agree you could definitely slow down the fan! Long slow burn times is what to shoot for. for a homemade, one of the nicer setups I've seen.
 
Nice job!
By the way, you didn't happen to find a piece of refractory in your ashes after that pop did you? Ceramics don't like uneven temperatures so limiting run time with the door open should be kept at a minimum.
 
image.jpg Right now the i have no control over primary air. It s just limited by the hole size of my primary air tube. This summer I am going to replace them with stainless and ad a valve for primary air. This way I can control the secondary flame better. The secondary I have a 2" valve normally all the way open, but after the volital gasses are burned off it would be better to cut the air back then. I have slowed the fan down and got slightly better burn times but it tends to leave more heavy ash in the primary chamber. Last night was about 8F as a low and I got 13 hours out of it and about 6" of coals left this morning. My house is at 74F and the shop is at 70F
See the trend, this is how much it normally cycles
what did you do to meter your primary/secondary air? and I agree you could definitely slow down the fan! Long slow burn times is what to shoot for. for a homemade, one of the nicer setups I've seen.
 
Thanks I am glad it works as good as it does because I would never here the end of it from my wife if it did not!
I did not see anything broke, the pop did catch me by surprise! I have had a nice poof before when I opened the primary door and once enough o2 got in it ignited and about burned some whiskers off. I try not to open the primary door only when I have too!


Nice job!
By the way, you didn't happen to find a piece of refractory in your ashes after that pop did you? Ceramics don't like uneven temperatures so limiting run time with the door open should be kept at a minimum.
 
3rd season on my homemade boiler and this, just happened on Monday!

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Was heating 6800 square feet this year! Was working great, had wind storm and fire Marshall says it was electrical service overhead that caused it! Sad day for me!

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I'm sorry. A lot work lost.
Will you build a new one?
 
Man like velvetfoot said that really and truly sucks bad!!!!! Did it destroy the whole boiler? Well at least it's almost spring so hopefully you guys don't freeze to death before it finally gets here. Hopefully you can salvage some of it so it's not a total loss. My thoughts and prayers are with you.
 
I sent born2burn a text but wanted to say it here too, This is terrible. when something like this happens you loose a piece of you. I want to than Born2Burn for all of his help with my project and extend to him that if there is anything that he needs from me I will be glad to assist in anyway possible.
 
Man like velvetfoot said that really and truly sucks bad!!!!! Did it destroy the whole boiler? Well at least it's almost spring so hopefully you guys don't freeze to death before it finally gets here. Hopefully you can salvage some of it so it's not a total loss. My thoughts and prayers are with you.
I definitely overheated it, I am up in the air on rebuilding, insurance said they will cover it. Not sure what to go with yet a garn maybe, I heat alot and I want it in a separate building but not outside unit


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I'm sorry. A lot work lost.
Will you build a new one?
I might build a new one, I hate to start the learning the unit all over again. Lot of work down the tubes

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Yeah. I hate what happened. I enjoy those do it yourself threads. But you're right, each design has a lot of nuances and you can burn up a lot of time tweaking.
My brother is burning a chip boiler from Heatmaster and this is the first year. It works well but a learning curve on settings, fuel types, etc. Lotta time invested.
 
Man that sucks! That looked like a nice build!
 
Man that sucks! That looked like a nice build!
Thanks,. I would be ready to go burn again but even if I get a new gasser I have no split wood for next season. Log splitter burned, silvy chain sharpener, chains all burned up. Going to take awhile to get back into it. I still have two saws yet.

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Can you get the log splitter and silvy covered with insurance?

Sorry to hear of all the fire damage with you and others with wildfires in the region. Good luck. Hang in there.
 
Can you get the log splitter and silvy covered with insurance?

Sorry to hear of all the fire damage with you and others with wildfires in the region. Good luck. Hang in there.
Sound like it will be covered, even though the splitter and boiler are homemade. I am having trouble finding a good gasser that will heat 6800 square feet and domestic hot water. I know the garn wood but I need a comparable downdraft model.


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