3
© Baxi Heating UK Ltd 2010
Combustible material should not be located where the heat dissipating through the
walls of fireplaces or flues could ignite it. Therefore when installing the boiler in the
presence of combustible materials due account must be taken of the guidance on the
separation of combustible material given in Building Regulations Approved Document J.
Clearances are also required for servicing around the appliance and to allow for
radiation directly in front of the appliance see section 2.5 of the main Assembly
Instructions.
Adequate provision (e.g. easily accessible soot door or doors) must be provided for
sweeping the chimney and connecting fluepipe.
CO-emissions related to 13% O
2
content at nominal / partial power 48/167 mg/m
N
3
.
Hearth
The hearth should be able to accommodate the weight of the boiler, and its chimney if
the chimney is not independently supported. The weight of the boiler is indicated in
the brochure.
The boiler should be installed on a non-combustible hearth of a size and construction
that is in accordance with the provisions of the current Building Regulations Approved
Document J.
The clearance distances to combustible material beneath, surrounding or upon the
hearth should comply with the guidance on the separation of combustible material
given in Building Regulations Approved Document J.
If the boiler is to be installed on a combustible floor surface, it must be covered with a
non-combustible material at least 12mm thick, in accordance with Building Regulations
Approved Document J to a distance of 30cm in front of the boiler and 15cm to each
side measuring from the door of the combustion chamber.
Combustion Air Supply
This is an open flued appliance. The air supply can be provided either directly from
outside via an air duct or from the room of installation. In order for the boiler to
perform efficiently and safely there must be an adequate air supply into the room in
which the boiler is installed to provide combustion air. The provision of air supply to
the boiler must be in accordance with current Building Regulations Approved
Document J. An opening window is NOT appropriate for this purpose.
Combustion air ventilation requirements for the 12kW Baxi Bioflo: -
Air vents must be fitted lower than 450mm when in vertical walls.
Alternatively the air supply may be provide via an air duct 75mm in diameter and up to
9m in length (reduced 1m in length for every 90° bend used) see section 2.3.4a of the
Assembly Instructions.
If an air vent duct is connected to the appliance for the provision of combustion air
then a terminal guard /grill must be fitted to prevent vermin etc. from entering the
appliance and or blocking the duct. A ball of 13 mm should not be able to pass
through the grill.
The installers should provide labels for the ducts and grilles with the following
information.
a) Air Inlet Duct Label. “This duct supplies air to a solid fuel appliance and its flueing
system. It should not be blocked or restricted under any circumstances. For more
information refer to the person responsible for the building; Name and contact
details...............”
b) Duct Grille Label. “The duct behind this grille supplies air to a solid fuel appliance
and its flueing system. It should not be blocked or restricted under any circumstances.
For more information refer to the person responsible for the building; Name and
contact details ...............”
Air permeability
To outside
Communicating walls
Older properties >5 m
3
/(h.m
2
)
38.5 cm
60 cm
2
Newer properties <5 m
3
/(h.m
2
)
66 cm
100 cm
2
