Hergom H-01 Instrucciones Para La Instalación, Uso Y Mantenimiento página 28

Over the years, you may change the type of fuel you use but, once the
chimney has been installed in a given place, it is not so easy to alter or
reposition.
Therefore, the following information will help you decide whether you can
use your present chimney or not, or whether you need to build a new one.
The base where you are going to place your Hearth must be flat and
provide a perfect seat for your Hearth. The base must be built using heat
resistant materials.
4.1.1 How chimneys work.
A basic knowledge of the dynamics of chimneys will help you make the most
of your HEARTH.
Chimneys:
a) Safely evacuate smoke and gasses from the house.
b) Provide sufficient draw in the hearth to keep the fire alive.
What is the "chimney draw"?
The tendency air has to rise generates the chimney effect.
When the HEARTH is lit, hot air rises through the chimney. The chimney
flue heats up and keeps it drawing. Until the chimney is hot enough, the
chimney effect will not work properly.
The chimney effect depends on the location, size and height of the chimney.
The following must be taken into consideration:
- Chimneys located inside a house keep warm and, therefore,
chimney draw is greater.
- The chimney size recommended by the manufacturer will provide
a good chimney effect.
- The height of a chimney affects how it draws: greater height,
better chimney effect.
The chimney must project at least one metre over the highest part of the
roof.
- 28 -