redlig
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Beautiful but I bet it gets hot at the apex of the ceiling.
- Thread starter julianf
- Start date
I will make sure we install extractor fans. Far cheaper than aircon.
And conversely in Winter suck the warmer air away from the roof and down.
gaz1
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@fizzy @julianf
you have 3 types to choose from
old style secondary air, poor design nowadays
downdraft model using secondary air, clean burn but suffers creosote within the fire chamber so be aware of this
rocket stove hybrid model
both of you know the rocket stove method via your rayburn, esse however these are old styles and secondary air usage is more effecient
old style secondary air would be this model
downdraft model would be this type within reason
rocket stove type i will have to discuss with you as you need to get it right and also which type of rocket stove maybe the best
but id advise a wear plate for thrown in lengths of pallets
now id advise building a 3mm small model to test first before you build the main unit
you have 3 types to choose from
old style secondary air, poor design nowadays
downdraft model using secondary air, clean burn but suffers creosote within the fire chamber so be aware of this
rocket stove hybrid model
both of you know the rocket stove method via your rayburn, esse however these are old styles and secondary air usage is more effecient
old style secondary air would be this model
downdraft model would be this type within reason
rocket stove type i will have to discuss with you as you need to get it right and also which type of rocket stove maybe the best
but id advise a wear plate for thrown in lengths of pallets
now id advise building a 3mm small model to test first before you build the main unit
redlig
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I was toying with the idea of installing a pipe across or along the floor of my woody and blowing the heated air across the floor at foot level.
pedrobedro
Man at Matalan
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wood you can't get
I don't agree with that.
Poplar and Goat Willow are rubbish for burning even when well seasoned.
Thats quite a reputation for a woman to have.
julianthegypsy
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Alder. Someone gave me some once. It was basically flame proof. Very heavy. Because it's 90% water.There is only one type of wood thats bad for burning
wood you can't get
julianf
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I doubt that my old man has ever, even once in his life, had his opinion changed on somthing by my actions -
He was wanting to burn the wet logs as when they're dry they burn too quick.
I got one of the logs, weighed it, and then left it in the oven on low over night. I weighed it again in the morning.
The moisture lost was about the same as a small wine glass full of water.
I tried to explain this to him. I can't remember quite how it went but it would have been the same as usual - disbelief but without any logical contradiction.
...and then business as usual. Those nice, slow burning, wet logs...
If you do the maths on wet wood (which I did years later, it wasn't part of that discussion at all) it's quite significant. You can estimate the joules from the fuel, the joules needed to raise [X] grams of water from 15c to 100c, then the energy required for the state change.
That bits all quite easy to calculate and you find you're wasting a significant percentage of your fuels total joules just boiling off the water.
But the bit that's harder to calculate is the losses that are suffered by keeping the burn cooler. All those lower flash point chemicals that just get "wasted" up the chimney as smoke / tars, when they could also be oxidised exothermically.
Mathematically it's so very much better (efficiency) to burn a small hot fire with dry wood.
...but that still doesn't stop me wanting to build a, possibly inefficient, fire to save me chopping up pallets!
He was wanting to burn the wet logs as when they're dry they burn too quick.
I got one of the logs, weighed it, and then left it in the oven on low over night. I weighed it again in the morning.
The moisture lost was about the same as a small wine glass full of water.
I tried to explain this to him. I can't remember quite how it went but it would have been the same as usual - disbelief but without any logical contradiction.
...and then business as usual. Those nice, slow burning, wet logs...
If you do the maths on wet wood (which I did years later, it wasn't part of that discussion at all) it's quite significant. You can estimate the joules from the fuel, the joules needed to raise [X] grams of water from 15c to 100c, then the energy required for the state change.
That bits all quite easy to calculate and you find you're wasting a significant percentage of your fuels total joules just boiling off the water.
But the bit that's harder to calculate is the losses that are suffered by keeping the burn cooler. All those lower flash point chemicals that just get "wasted" up the chimney as smoke / tars, when they could also be oxidised exothermically.
Mathematically it's so very much better (efficiency) to burn a small hot fire with dry wood.
...but that still doesn't stop me wanting to build a, possibly inefficient, fire to save me chopping up pallets!
julianthegypsy
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Absolutely. Small, blazing hot fire every time. Even better, short really hot fire and heat up a large thermal mass to release the heat for hours after the fire has burned out.
If you want to build a big one, use a computer fan to give it some forced draft. That'll get the flames dancing and the efficiency up!
magnet
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The way i look at it when there's horizontal sleet lashing off my windows mid winter im glad of any wood i can get thats dry. More so now that the gas boiler has become an industrial art installation since the price of gas went through the roof. In a nutshell i suppose, beggars cant be choosers.
gaz1
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my comment would be simple the reason why your chimney is so bad is due to poor wet wood being used coating up the insides of your chimney with clinkers (creosote ) and tar
the best way of starting a chimney fire which would burn your house down
either stop doing it or risk burning your house down
dosnt matter if its uk, usa or anywhere else
i use both videos when installing woodstoves to explain why to keep your chimney swept
AVI_8
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Totally agree and if you’ve a log burner or multi fuel burner with a flue it’s a diy job, I do mine every year with rods and a centrifugal brush attached to a cordless drill, usually get half a bucket of ash on a 9 metre flue, and that’s burning seasoned wood and smokeless fuel.
I‘ve seen a chimney fire when I was a child on our farmhouse chimney, the chimney pot was like a bunsen burner, you don’t want that!
I‘ve seen a chimney fire when I was a child on our farmhouse chimney, the chimney pot was like a bunsen burner, you don’t want that!
In our old farmhouse I would have to sweep the Rayburn chimney every month. I would get 2 carriers full of soot out each time. The draw was awful. There was an inspection hatch for sweeping. Inner steel plate and outer steel door with rockwool between. We had several chimney fires. Very scary. One of them actually melted the rockwool 
I thought it was burning crap pallet wood.
In our new farmhouse there is a big woodburner with a modern chimney liner. Forgot to sweep it last year. So after 2 years barely a sugar bag amount of soot. Amazing. Obviously not the wood!
I thought it was burning crap pallet wood.
In our new farmhouse there is a big woodburner with a modern chimney liner. Forgot to sweep it last year. So after 2 years barely a sugar bag amount of soot. Amazing. Obviously not the wood!
AVI_8
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That’s not a lot of soot, mines running 8 hours a day, every day usually September until AprilIn our old farmhouse I would have to sweep the Rayburn chimney every month. I would get 2 carriers full of soot out each time. The draw was awful. There was an inspection hatch for sweeping. Inner steel plate and outer steel door with rockwool between. We had several chimney fires. Very scary. One of them actually melted the rockwool
I thought it was burning crap pallet wood.
In our new farmhouse there is a big woodburner with a modern chimney liner. Forgot to sweep it last year. So after 2 years barely a sugar bag amount of soot. Amazing. Obviously not the wood!
Farside
Badly Welded Man
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I put an underfloor heating system into a new-build oak barn with similar roof height indoors, as those above.
Paddy, the owner, had a fit of the vapours when the fuel oil bills came in.
Well, he insisted on being warm... and it was him who'd gone through the architects' specs and deleted the heat recovery system to keep the costs down.
gaz1
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the thing is its not its a rocket stove at 2000f
and it has the roar to it as well
its like this video with full volume from your speakers
HydrocarbonPrimate
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I suspect this is stupid question, but can you burn MDF in a rocket stove?, I can get hold of significant amount of mdf from work, and it seems like a huge waste of energy going in the bin.
julianthegypsy
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I wouldn't personally, it contains huge amounts of glue. It might just burn off in a rocket I suppose, but my experience with ordinary burners and anything like MDF makes me cringe at the thought of it!
julianf
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If I was wanting to burn that kind of stuff, I'd be seeking very high temperatures and a significant dwell time.
There are a few commercial stoves that have meshes that are supposed to super heat and burn off any smoke particulate matter. Who know if the work, but I'd feel most confident if the stove was good an insulated and the ways were sufficient to keep the exhaust gas at a high temperature all the time.
Would need attention with refueling to maintain the constant high temperature.
I'm sure it would be possible but I suspect without automation or a lot of manual control, the temperature would fall, and it would start spewing unburnt nasties.
There are a few commercial stoves that have meshes that are supposed to super heat and burn off any smoke particulate matter. Who know if the work, but I'd feel most confident if the stove was good an insulated and the ways were sufficient to keep the exhaust gas at a high temperature all the time.
Would need attention with refueling to maintain the constant high temperature.
I'm sure it would be possible but I suspect without automation or a lot of manual control, the temperature would fall, and it would start spewing unburnt nasties.
