Solid Fuel Not Getting Hot?

[magnetman]

One interesting thing I have discovered is if the fire is burning very hot then wet or green wood seems to burn hotter than dry wood. I think there actually is more energy in green wood its just that in most cases the fire is not hot enough to immediately convert the water to steam. 

 

Therefore the effect of adding green wood is usually to reduce the heat. However above a certain temperature and with preheated secondary air the green wood is a very good fuel. 

 

In houses it can be a problem because of chimney fires but in a small stove with a metal flue which is itself also very hot there is no opportunity for condensation. 

 

 

 

For secondary burn the firebox needs to be 600'C. A lot of fired are slightly oversized so getting up to this temperature could result in a ridiculously warm cabin. 

 

3 minutes ago, booke23 said:

 

Ah yes I've experienced that before with smokeless products. The only way to know for sure is to look up the MSF number (This has to be displayed by law) on the bag rather than go by the name. I've seen some fuels with three different formulations under one name....I suppose it depends on what ingredients the yard has lying around when they are making it!

Good tip about the MSF number. I guess its an economics thing as well based on the purchase price of the constituent products. 

 

 

[Tonka]

1 hour ago, nealeST said:

I'm also scientifically challenged and I'm not bothering to google anything. For two and half decades  I have felled and chopped Silver Birch, Spruce, Ash and Pine. I currently have a huge amount of Elm seasoning for next year all this winter that was chopped before midsummer. I can share with you that all the above combust at different rates, have different densities and certainly look and smell different. Silver Birch is my absolute favourite, is nice dense wood with fine grain. Pine goes like a rocket, can be quite sappy even when seasoned and is rated anecdotally as being good for clearing out your chimney as it burns fast. Silver Birch is a slow burner but the Elm wood is hard as nails and burns the slowest I've seen. Overall silver birch burns optimally with loads of heat output. As mentioned I always chop, by which I mean split the wood before midsummer and it drys outside until August where upon it is moved and stacked neatly for air ventilation in a purpose built wood shed. It remains there all winter until the following Autumn when, as per tradition and for countless centuries of practise the wood is now seasoned and ready to go. Not being an expert I'm not going to disagree with generations of people who have done this for a lifetime, I just follow suit. The stuff I've seen in petrol stations and in bargain stores in plastic bags looks that people take home to burn whilst they have their gas fired central heating running in the background feels nothing like it should. The fact that it is heated to dry it out means that energy that could be stored in the wood has been forced out leaving you with something combustable but very short term ie it will burn fast...just like chipboard or even cardboard.  I'm sure the text on the plastic wrapper is convincing in its claims about how much better it is to for-go the time honoured way of seasoning wood but as far as I can see the difference between the two is vast and I'm quite happy to make my own mind about that. I am suspicious in general of things that are processed and claim to be better.....

Hardwood which is from deciduous trees is better than Softwood which are evergreen trees I.e Pine

Balsa is a hardwood

[magnetman]

Flowering trees generally make the best firewood.

 

[Jerra]

17 minutes ago, magnetman said:

Flowering trees generally make the best firewood.

 

Which is basically the same as saying hardwoods are better than softwoods.

[Peanut]

I think the underlying problem here, is a lack of the available resources needed, or a reluctance to part with them, to replace the installation, which is both unsafe and inadequate for the task.

[magnetman]

To be fair if it could have a single piece flue pipe it might be fine.

 

Putting the bricks in the reduce the firebox size is an interesting approach and can work but it is encouraging the fire to operate at the wrong temperature for its design. 

 

The fire is too big for the boat. I still think a 4 inch straight stainless steel flue 1.5mm wall thickness on it might help a lot. 

 

 

With that silly cobbled together flue there is too much surface area and it won't get hot enough to draw properly. 

If the boat is permanently moored there is an argument for having the flue long enough to include 18 inches above the deck going through one of those silicone flashings. 

 

removable terminals are desirable on cruising boats for bridges but a single piece flue with enough external to get the smoke away from vents is going to work better. Collars and removable terminals always cause problems. 

 

The fire and the flue form part of a circuit which needs to be optimised in order to work correctly. 

 

Once you get the flue outdoors it will obviously get cooled down so having it too long, although it follows flue length guidance, might be counterproductive. 

[rusty69]

What he said. No need to condemn the stove just yet, just work on the flue and deck collar connection. 

[tree monkey]

5 hours ago, magnetman said:

 

 

Angiosperm wood tends to be more dense than gymnosperm wood. 

 

 

Is where someone mentions balsa and cedar?

 

[magnetman]

'tends to be' not 'is'

[tree monkey]

1 hour ago, Jerra said:

Which is basically the same as saying hardwoods are better than softwoods.

And it's a bit simplistic as well, yes hardwoods tend to be more energy dense, if I could source sufficient hawthorn I would be a happy man but some softwoods make very decent firewood

[magnetman]

1 minute ago, tree monkey said:

And it's a bit simplistic as well, yes hardwoods tend to be more energy dense, if I could source sufficient hawthorn I would be a happy man but some softwoods make very decent firewood

 

Yup. 

My favourite by far. My fire is full of hawthorn right now actually. 

[tree monkey]

3 hours ago, nealeST said:

I'm also scientifically challenged and I'm not bothering to google anything. For two and half decades  I have felled and chopped Silver Birch, Spruce, Ash and Pine. I currently have a huge amount of Elm seasoning for next year all this winter that was chopped before midsummer. I can share with you that all the above combust at different rates, have different densities and certainly look and smell different. Silver Birch is my absolute favourite, is nice dense wood with fine grain. Pine goes like a rocket, can be quite sappy even when seasoned and is rated anecdotally as being good for clearing out your chimney as it burns fast. Silver Birch is a slow burner but the Elm wood is hard as nails and burns the slowest I've seen. Overall silver birch burns optimally with loads of heat output. As mentioned I always chop, by which I mean split the wood before midsummer and it drys outside until August where upon it is moved and stacked neatly for air ventilation in a purpose built wood shed. It remains there all winter until the following Autumn when, as per tradition and for countless centuries of practise the wood is now seasoned and ready to go. Not being an expert I'm not going to disagree with generations of people who have done this for a lifetime, I just follow suit. The stuff I've seen in petrol stations and in bargain stores in plastic bags looks that people take home to burn whilst they have their gas fired central heating running in the background feels nothing like it should. The fact that it is heated to dry it out means that energy that could be stored in the wood has been forced out leaving you with something combustable but very short term ie it will burn fast...just like chipboard or even cardboard.  I'm sure the text on the plastic wrapper is convincing in its claims about how much better it is to for-go the time honoured way of seasoning wood but as far as I can see the difference between the two is vast and I'm quite happy to make my own mind about that. I am suspicious in general of things that are processed and claim to be better.....

Much of the quality of the wood is from how dense it is, some of that is species dependant and some is speed of growth, what won't lower heat output is reduced water content from kiln drying.

A lump of wood with <20% water content is the same if open seasoned or kiln dried

8 minutes ago, magnetman said:

 

Yup. 

My favourite by far. My fire is full of hawthorn right now actually. 

Lucky sod

[magnetman]

Firewood poem (from memory) 

 

Oak and maple if dry and old 

will keep away the winters' cold.

 

Birch and fir logs burn to fast

blaze up bright and do not last. 

 

Elm wood burns like churchyard mould

even the very flames are cold! 

 

Poplar gives a bitter smoke

fills your eyes and makes you choke. 

 

Beech wood fires are bright and clear

if the logs are kept a year. 

 

Chestnut only good they say 

if for long tis laid away. 

 

Apple wood will scent your room 

with an incense-like perfume

 

It is by the Irish said 

that Hawthorn bakes the sweetest bread. 

 

Ash wood wet or ash wood dry 

a king shall warm his slippers by.

 

...

 

Alternative to the last one 

 

Ash seer or ash green 

its fit for the queen. 

 

 

 

There will be others !