FLUE & CHIMNEY CONNECTION TO STOVE
The outlet from the chimney should be above the roof of the building in accordance with the
provisions of Building Regula�ons Approved Document J. If installa�on is into an exis�ng chimney
then it must be sound and have no cracks or other faults which might allow fumes into the house.
Older proper�es, especially, may have chimney faults or the cross sec�on may be too large .
Mendip Stoves recommend the use of a solid fuel flue lining system for all installa�on into exis�ng
chimneys. All chimney systems must be used in accordance with Building Regula�ons Approved
Document J.
If an exis�ng chimney is used the chimney must be clear of obstruc�on and be swept clean
immediately before installa�on of the stove. The chimney should be tested to confirm the chimney
will provide the correct chimney pressure for the stove. If the stove is fi�ed in place of an open fire
the chimney should be swept one month a�er installa�on to clear any soot falls which may have
occurred due to the difference in combus�on between the stove and the open fire. If there is no
exis�ng chimney then either a prefabricated block chimney in accordance with Building Regula�ons
Approved Document J or a twin walled insulated stainless steel flue to BS 1856-1 . These chimneys
must be fi�ed in accordance with the manufacturer’s instruc�ons and Building Regula�ons. A single
wall metal flue pipe is suitable for connec�ng the stove to the chimney but is not suitable for using for
the complete chimney. The connec�ng flue pipe must have a minimum diameter of 125 mm and its
dimension should be not less than the size of the outlet socket of the stove. Registered smoke exempt
models with a 125mm collar burning wood only can be installed on a flue of 125mm throughout. Any
bend in the chimney or connec�ng flue pipe should not exceed 45°. 90° bends should not be used
other than within 150mm of stove rear flue outlet.
Chimney Connec�on
In order for the stove to perform sa�sfactorily the chimney height must be sufficient to ensure an
adequate draught to clear the products of combus�on and prevent smoke problems into the room.
A chimney height of not less than 4.5 metres measured ver�cally from the outlet of the stove to the
top of the chimney should be sa�sfactory. Alterna�vely the calcula�on procedure given in
BS5854:1980 may be used as the basis for deciding whether a par�cular chimney design will provide
sufficient draught.
If it is found that there is excessive draught in the chimney then either an adjustable flue damper or
alternately a draught stabiliser should be fi�ed. The adjustable flue damper should not close off the
flue en�rely but should in its closed posi�on leave a minimum con�nuous opening free area of at
least 20 % of the total cross sec�onal area of the flue or flue pipe. Adequate provision e.g. easily
accessible soot door or doors must be provided for sweeping the chimney and connec�ng flue pipe.
Your appliance needs to be maintained rou�nely, the throat plate/baffle should be cleaned regularly
(monthly) . The flue pipe can be cleaned using a flexible brush. Only Use a dry cloth on external
surfaces. Over �me the glass may become dirty, clean with a damp cloth and polish off with damp
cloth. If the stove has not been used for some �me the flue should be checked for blockages before
use. Do not modify the appliance; only use spares authorised by the manufacturer.
Tested Gas flow rates flue
gas temperatures
Flue gas
flow rate
Test flue gas temperature
wood
@ pascals of
pressure
Woodland Double sided
5.7 g/s
253°C
12
