Hergom MALLORCA Instrucciones Para Instalación, Uso Y Mantenimiento página 33

It is vital that the joins of the sections of the chimney are correctly sealed. (See Fig.-
7, Page.8).
B.- Chimneys.
The operation of your Mallorca fireplace depends on:
d) The chimney.
e) The way in which it works in conjunction with the chimney.
f) The quality of fuel used.
After some years you can change the type of fuel but once the chimney has been
built it is not easy to change its position.
1. – How chimneys work
A basic understanding of how chimneys work will help you to get the best out of
your Mallorca fireplace.
A chimney is:
a) To safely take smoke and gases away from the house.
b) To provide enough draft in the fireplace for the fire to stay alight.
What is draft?
The tendency of hot air to rise creates a draft.
When the stove is lit hot air goes up the chimney and out through the chimney top.
The chimney flue heats up and maintains the draft. The draft will not work at full efficiency
until the stove and the chimney are hot.
The situation, the size and the height of the chimney affect the draft.
The following points must be taken into consideration:
- Chimneys situated inside the house keep hot so the draft is greater.
- The size of the chimney advised by the manufacturer will maintain a good draft.
- The height of the chimney affects the draft:
The chimney must be at least one metre higher than the highest part of the roof.
Other factors which affect the draft are:
- In houses which are very well internally insulated, with no drafts, as no air enters
the premises this impedes the draft. This is corrected by seeing that air from the outside
gets to the stove.
- High trees and/or buildings close to the dwelling impede the draft.
- Wind speed. Generally continuous, high winds increase the draft, but stormy winds
reduce the draft.
- The outside temperature. The colder it is outside the better the draft.
- Air pressure. On rainy, damp or foggy days the draft is generally poor.
- The temperature of the fire. The hotter the fire the stronger the draft.
The higher the chimney the better the draft.
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