98
Metal Parts
When installing or servicing this boiler care should be taken to avoid the possibility of personal
injury.
BOILER PERFORMANCE
Refer to the main instruction manual for details of the boiler’s performance.
PREPARATORY WORK AND SAFETY CHECKS
IMPORTANT WARNING
This boiler must not be installed into a chimney that serves any other heating appliance.
There must not be an extractor fan fitted in the same room as the boiler as this can cause the
boiler to emit fumes into the room.
Chimney
In order for the boiler to perform satisfactorily the chimney height must be sufficient to ensure an
adequate draught of approximately 15 Pa so as to clear the products of combustion and prevent
smoke problems into the room.
NOTE: A chimney height of not less than 4.5 metres measured vertically from the outlet of the
boiler to the top of the chimney should be satisfactory. Alternatively the calculation procedure
given in EN 13384-1 may be used as the basis for deciding whether a particular chimney design
will provide sufficient draught.
The outlet from the chimney should be above the roof of the building in accordance with the
provisions of Building Regulations Approved Document J.
Because the boiler runs at high efficiencies, the temperature of the flue gases is at times lower
than conventional solid fuel appliances. Although it is not classed as a condensing appliance,
the low flue gas temperature results in condensation occurring within the flue. Any chimney flue
system must therefore be able to withstand the effects of condensate and operate under wet
conditions (designation letter W). In addition it should be soot fire resistant and able to withstand
the corrosive effects of flue products generated by solid fuels (designation G and 3
respectively). If installation is into an existing masonry chimney then it will require re-lining with
a liner meeting the specification described above. Existing concrete or clay lined chimneys are
not suitable for this boiler and must be lined as described above. All installations must be in
accordance with Building Regulations Approved Document J.
Any existing chimney must be clear of obstruction and have been swept clean immediately
before installation of the lining system. Where the chimney is believed to have previously served
an open fire installation it is possible that the higher flue gas temperature from a closed
appliance 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.
