three metres, restrictive terminations, etc.
3.2.4
If the fireplace opening is greater than the acceptable dimensions given in this
guide, do not use the back of a fire surround or marble to reduce the opening. This may
cause cracking of the surround back or marble.
3.3
The following flues are suitable:
!
225mm x 225mm conventional brick flue.
If a flue liner is used, it must be a minimum of 125mm diameter. The liner must be
sealed to the surrounding area above the fireplace opening and to the top of the
chimney. An approved terminal must be fitted.
!
A properly constructed precast flue conforming to B.S 1289 or BS EN 1858.
!
A flue pipe with a minimum diameter of 127mm. See B.S 6461 Part 1 for suitable
materials. Metal flue pipes must comply with BS EN 1856 Part 1 or B.S 715.
3.3.1
The minimum effective height of the flue must be 3m.
3.3.2
The flue must be clear of any obstruction and its base must be clear of debris.
3.3.3
The flue must be completely sealed so that combustion products do not come into
contact with combustible materials outside the chimney.
3.3.4
The flue must serve only one fireplace.
3.4
The flue must conform to BS 5440: Part 1 in design and installation.
The flue, measured from the bottom of the fireplace opening to the bottom of the
terminal, shall be not less than 3m in actual vertical height. When calculated in
accordance with BS 5440: Part 1 Annex A, the minimum
equivalent
height of the flue
shall be 2.0m of 125mm dia. flue pipe.
3.5
The flue must not be used for any other appliance or application.
3.6
Any chimney dampers or restrictors should be removed. If removal is not
possible they must be fixed in the open position.
3.7
If the appliance is intended to be installed to a chimney, which was previously
used for solid fuel, the flue must be swept clean prior to installation. All flues should be
inspected for soundness and freedom from blockages.
3.8
If the fireplace opening is an underfloor draught type, it must be sealed to stop
any draughts.
3.9
The appliance must be mounted behind a non-combustible hearth (N.B.
conglomerate marble hearths are considered as non-combustible) unless the conditions
of section 3.2.1.1 are met. The appliance can be fitted to a purpose made proprietary
class “O”-150°C surround. The hearth material must be at least 12mm thick. The
periphery of the hearth (or fender) should be at least 50mm above floor level to
Page 10
INSTALLER GUIDE
©
Baxi Heating U.K. Limited 2007.
