Flue And Chimneys - Hamlet DEFRA Installation And User Manual

3 Flue and Chimneys

The stove must be connected to a suitable and e cient ue so that products
of combustion (fumes) from the stove are expelled to the outside air. Please
remember that chimney draught is dependent on four main factors :
• Flue gas temperature
• Flue height
• Flue size
• Flue terminal
To ensure a good up draught it is important that the ue gases are kept warm
and that the ue size suits the stove. The termination of the outlet at the top of
the ue also needs to comply with Building Regulations. The minimum e ective
height of the ue must be at least 4.5 metres from the top of the stove to the
top of the ue outlet. When warm the ue draught should be between 0.1 to 0.2
mb.
The draw of a chimney / ue can vary in di erent weather conditions and the
customer should be made aware of this.
Failure to correct an over-drawing ue will invalidate the warranty.
A chimney may comply with regulations but could still be subject to down
draught and similar problems. A chimney terminating above the ridge level is
generally less likely to su er such problems.
If a new chimney is being provided it should fully comply with the relevant
Building Regulations that specify the requirements for solid fuel burning
installations. Suitable types of chimney include the following :
• Masonry Chimney : Built with clay or concrete liners, or a chimney
block system meeting Building Regulations. These types of chimneys
should be installed in accordance with the Building Regulations and BS EN
15287-1:2007.
• Factory Made Insulated Chimney : Complying with BS 4543:Part 2 (often
called Class 1 prefabricated metal chimney). These types of chimneys should
be installed in accordance with Building Regulations and BS EN 15287-1:2007.
BK575 Rev03
DEFRA Stove Installation and User Guide
8