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Liveliness of the fire. The hotter the fire, the stronger the draught.
Cracks in the chimney, a badly sealed or dirty door, entry of air at tube joints,
another device connected to the chimney etc. can cause inadequate draughts.
2.1.2. Formation of creosote and cleaning.
When wood is burned slowly, tars and other organic vapours can accumulate in the
flue which when combined with the atmospheric humidity form the creosote. The
creosote vapours can condensate if the walls of the chimney are cold. If it ignites the
creosote can cause extremely intense fires. Any accumulation of creosote must be
eliminated. Given that the accumulation of creosote depends on so many variables, it
is very difficult to predict when the chimney must be cleaned. Visual inspections are
the safest way to be certain that the fireplace is free of creosote and we therefore
recommend installing it in such a way that makes it easy to access.
2.1.3.
Options.
If you are going to build a chimney for the FIREPLACE, you have two options:
A brickwork chimney.
A metal chimney.
The studies show that there is little difference between metal and brickwork in terms
of draught performance. You can choose the one that most suits your home.
Whenever possible, position the chimney inside the house; this will provide a better
draught, accumulate less creosote and the chimney will last longer.
THE ADVANTAGES OF BRICKWORK CHIMNEYS ARE:
The bricks and tiles reduce the cooling of the smoke in the chimney.
The brickwork’s ability to store heat keeps the home warmer for longer after the fire
has gone out.
It can be built to the individual’s taste.
If it is well built it can be more fire resistant than the metal chimneys.
Brickwork chimneys must be well lined in order to prevent the smoke from cooling.
They must be built from materials that withstand high temperatures and corrosion.
They can be round, square etc; the important thing is their inner cross section.
For brickwork chimneys the measurements described in the 9. TECHNICAL
INFORMATION section must be used.
THE ADVANTAGES OF METAL CHIMNEYS ARE:
Easy to install.
Allows slight changes in the direction of the chimney which provides more flexibility
when choosing where to install the FIREPLACE.
Thanks to its curved elbows the sharp angles which restrict draught are eliminated.