PUTTING IT ALL TOGETHER
10
BENDS IN FLUES
Offsets in flues are only acceptable if the following rules are respected:
a) The chimney system shall have no more than 4 bends in total; - 2 bends in the chimney
and 2 bends in the flue pipe connection.
b) The offset shall provide a change of direction no more than 45 degrees from the
vertical.
c) The run of the chimney between bends shall not exceed 20% of the total chimney
length.
d)
The maximum length of the horizontal flue must not exceed 150mm (6”).
INSPECTION AND CLEANING
Check that the chimney is in good condition, dry and free from cracks and obstructions. The
diameter of the chimney should not be less than 150mm and not more than 230mm. If any
of these requirements are not met, the chimney should be lined by a suitable method.
The chimney must be swept before connection to the fireplace. Where the chimney is
believed to have previously served an open fire installation, it is possible that the higher flue
gas temperature from the fireplace may loosen deposits that were previously firmly
adhered, with the consequent risk of flue blockage. It is therefore recommended that the
chimney be swept a second time within a month of regular use after installation.
Assuming that when the fireplace is first installed, the chimney is clean, and sound, then the
chimney flue should be inspected part way through the burning season to establish the
regularity of sweeping required. If you have any doubts about the suitability of your
chimney, consult your local dealer/stockiest.
INSPECTION AND CLEANING
Any room or space containing a fireplace should have a permanent air vent opening of at
least the sizes shown in the table below. For fireplaces designed to burn a range of different
solid fuels, the air supply should be designed to accommodate burning the fuel that
produces the highest heating output.
FIREPLACE AIR SUPPLY
Permanently open vents as below:
Stove with no flue draught stabilizer
If design air permeability > 5m³/h.m²
then 550mm²/kW of appliance rated output
above 5kW
If design air permeability < 5m³/h.m²
then 550mm²/kW for balance of appliance rated
output
