Hergom H-03/70 Instrucciones Para Instalación, Uso Y Mantenimiento página 21

B. - Chimneys.
The functioning of the WOOD BURNER depends on:
d) The chimney.
e) The mode of operation.
f) The quality of the fuel used.
During the years of service you may change the type of the fuel you use, but the
chimney once installed will always be located in a specific place. It is not easy to modify or
change the location.
For this reason the following information will help you decide if you can use the
existing chimney or not, or whether to decide to build a new one.
This information will help you to make the correct decision.
1. - How do chimneys work?
Basic knowledge of how chimneys work will help you to get the best performance from
your H-03 Wood Burner.
The function of the chimney is:
a) To safely remove the smoke and gases from the house.
b) To provide sufficient pull in the wood burner for the fire to stay alight.
What is the pull?
The tendency for hot air to rise creates the pull.
When the WOOD BURNER is lit, the hot air rises through the chimney and is released
outside. The chimney duct heats up and maintains the pull. Only once the heater and the
chimney are hot, does the pull work perfectly.
The location, size and height of the chimney affect the pull.
It is necessary to consider the following:
- Chimneys located within the house remain hot; so the pull is better.
- The size of the chimney recommended by the manufacturer, maintains a good pull.
- The height of the chimney affects the pull: more height
The chimney must project at least one metre above the highest part of the roof.
There are other factors which affect the pull:
- Houses which are very well insulated, without air currents: air not entering the
building causes poor pull.
BURNER.
- High trees and/or buildings near to the house make the pull difficult.
- Wind speed. Generally continuous strong winds increase the pull; but stormy winds
decrease the pull.
- Exterior temperature. The colder it is outside the better the pull.
- Barometric pressure. On rainy, damp or stormy days, the pull is generally weak.
- Liveliness of the fire. The hotter the fire the stronger the pull.
- Cracks in the chimney, a poorly sealed or dirty door, air entering through the tubing
connections, other appliances being connected to the chimney, etc. can cause inadequate
pull.
This is corrected by taking air from outside to the WOOD
less pull