Hergom ARANDA Instrucciones Para La Instalación, Uso Y Mantenimiento página 53

- Barometric pressure. On rainy, humid or stormy days, the draught
is generally weak.
- Liveliness of the fire. The hotter the fire, the stronger the draught.
- Cracks in the chimney, badly sealed or dirty doors, air inlets through
the tube joints, other appliances connected to the chimney, etc. may
produce unsuitable draughts.
2.- Creosote formation and cleaning
When wood is burned slowly, tars and other organic vapours are produced
that, when combined with atmospheric humidity, form creosote.
The creosote vapours can be condensed if the chimney walls are cold. If
the creosote catches alight, extremely hot fires may be caused.
Any accumulation of creosote must be removed.
Due to the accumulation of creosote depending on many variables, it is
very difficult to predict the moment at which the chimney must be cleaned.
A visual inspection is the safest way of knowing whether the chimney of
your stove is clean of creosote.
We therefore recommend installations to which access is easy.
3.- Options
If you are going to build a chimney for your oven you have two
alternatives:
a) Brickwork chimneys.
b) Metal chimneys
Studies reflect that there is no great difference between metal and
brickwork in terms of draught. It is you who, according to each case, will
choose one or another.
Whenever possible, place your chimney inside the home to obtain a better
draught and accumulate less creosote, leading to a longer working life.
The advantages of brick chimneys are:
a) The mass of bricks and tiles reduces the cooling of smoke in
the chimney.
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