1.7 FITTING TO FIREPLACES WITH EXISTING CHAIRBRICKS AND
CONVENTIONAL BRICKBUILT CHIMNEYS
This appliance is not suitable for use in fireplaces fitted with an existing chairbrick,
when installing a cast fascia and surround. Any chairbrick must be removed prior
to proceeding with the installation. If installing the tray on its own, the chairbrick
can be left in position.
1.8 FITTING TO PRE-FABRICATED TWIN WALL METAL FLUE BOXES
The appliance may be fitted to twin wall metal flue boxes conforming to the
constructional requirements of BS 715, (for example the Ritevent LFE 175 box).
The box must have a minimum flue diameter of 125mm internal and minimum
internal dimensions of 300mm deep by 580mm high by 470mm wide. There are
no maximum dimensional requirements for the box. The top face of the box must
be insulated with a minimum thickness of 50mm of non-combustible mineral wool
insulation or similar material. The flue box must stand on a non-combustible base
of minimum thickness 12mm. Note : If fitting this product with a 175mm diameter
flue liner, 3 metres minimum effective flue height is required, if fitting with a 125mm
diameter flue liner, 4 metres minimum effective flue height is required.
1.9
HEARTHS
This appliance must only be installed on to a concrete or non-combustible hearth.
The hearth material must be a minimum thickness of 12mm with the top surface at
least 50mm above the floor. The hearth must be fitted symmetrically about the fire
opening and have a minimum width of 760mm and a minimum projection of
300mm forwards from the fire opening.
1.10
SPILLAGE MONITORING SYSTEM
This appliance is fitted with an atmosphere sensing spillage monitoring system in
the form of an oxygen sensing pilot. This is designed to shut the fire off in the
event of a partial or complete blockage of the flue causing a build up of
combustion products in the room in which the fire is operated.
The following are
important warnings relating to this spillage monitoring system
:-
1) The spillage monitoring system must not be adjusted by the installer.
2) The spillage monitoring system must not be put out of operation.
3) When the spillage monitoring system is exchanged only a complete original
manufacturers part may be fitted.
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