EQUATION EQH-80 S Manual De Usuario página 26

1. - How chimneys work
A basic knowledge of the dynamics of chimneys will help you make the most of your Built-in Fireplace
EQH.
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 a FIREPLACE is lit, hot air rises through the chimney. The chimney flue heats up and keeps it
drawing. Until the fireplace and the chimney are 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:
The chimney must project at least one metre over the highest part of the roof.
Other factors also affect chimney draw:
- Houses that have very good internal insulation, free from draughts, provide inadequate draw as no air
enters the building. This can be corrected by allowing external air to reach the FIREPLACE
- High trees and/or buildings near the house also have a negative effect on chimney draw.
- Wind speed. Usually, sustained strong winds increase chimney draw but stormy winds have a negative
effect.
- External temperature. The colder it is outside, the greater the chimney effect.
- Atmospheric pressure. The chimney effect is usually poor on rainy, damp or stormy days.
- Intensity of the fire. The hotter the fire, the stronger the chimney effect.
- Cracks in the chimney, badly sealed or dirty doors, air entering through pipe joints, other devices
connected to the chimney.... may have a negative effect on chimney draw.
2. - Creosote formation and cleaning.
When wood burns slowly, it produces tar and other organic fumes that, when combined with a damp
atmosphere, form creosote. Creosote fumes may condense if the chimney walls are cold. If it catches
fire, extremely tall fires may be caused. Any accumulation of creosote must be eliminated.
As the accumulation of creosote depends on a number of variables, it is very difficult to know when the
chimney should be cleaned.
The safest way of ensuring that the chimney of your fireplace is creosote free is by performing a visual
inspection.
Consequently, we recommend building installations that are easy to access.
greater height
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better chimney effect