Chimney and fire stuff
Feb 8th 2010, 4:30 pm
#121
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think I will stick with the 12 months thanks.
Feb 9th 2010, 8:32 am
#123
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Re: Chimney and fire stuff
To test how wet a piece is, take one reasonably clean log, weigh it on a gram accurate scle and place it by the fire. Weight it each week until it stops losing weight, and the weight lost in grams will be equal to the volume of water in ccs. That water takes a huge amount of water to boil away.
Remember, that it isn't just a case of bringing that water to the boil, you actually have to boil it away. When you have determined the amount of water in the log, if a typical stove full is five or six logs put 6 times that amount in a saucepan, and see how long that takes to boil away.
From that if you know the power of the stove, you can calculate the energy wasted. Multiply that by the number of times you fill the stove a day and you will have the day's wastage.
Of course on top of that there's the consideration that this will increase the risk of creosote formation.
Feb 9th 2010, 10:03 pm
#124
Straw Man.
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Feb 10th 2010, 10:00 am
#125
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Re: Chimney and fire stuff
Matt, I'd have to say that IMO, based on a fair bit of experience, any wood can produce tar/creosote under the 'right' conditions.
You could actually test this, by putting some ash fragments into a heat resistant, sealed glass container and heating them. Once the oxygen is used up, you might see the heat breaking the long chain carbon molecules into the (comparatively) short chain tars and creosotes.
In the stove, that's more or less what happens. There is a low level of air supplied, enough to burn off some volatiles, and break a lot of the chains, but not enough to complete the combustion process.
It is possible to tar up the flue of an open fire, but it's nowhere near as common. Open fires have such a free supply of air, and the flue gasses are so wastefully hot that condensation in the flue is usually restricted to soot.
You could actually test this, by putting some ash fragments into a heat resistant, sealed glass container and heating them. Once the oxygen is used up, you might see the heat breaking the long chain carbon molecules into the (comparatively) short chain tars and creosotes.
In the stove, that's more or less what happens. There is a low level of air supplied, enough to burn off some volatiles, and break a lot of the chains, but not enough to complete the combustion process.
It is possible to tar up the flue of an open fire, but it's nowhere near as common. Open fires have such a free supply of air, and the flue gasses are so wastefully hot that condensation in the flue is usually restricted to soot.
