Air Supply; Compartment Installation - Keston 30C Installation And Servicing Instructions

09 FLUE SYSTEM.... CONT'D
SLOPE
'Horizontal' flue outlet pipework MUST slope at least 2 degrees
(32mm per metre run) downwards towards the boiler. Pipework
can be vertical. Only swept elbows can be used.
Air inlet pipework can be truly horizontal or vertical, or sloping in
a downward direction towards the boiler but in each case rain,
etc., must be prevented from entering the pipe. There must be
no troughs in any of the pipework, whether it be air inlet or
flue outlet.
Due to the low temperature of the flue gases further
condensate will form within the flue system. Drain points, with
suitable traps, must therefore be incorporated within the flue
system at the base of the vertical flue sections in excess of 6m,
for 50mm muPVC pipe flue systems. These additional
condensate drains must be run to discharge. Such drain points
can be formed using standard muPVC fittings. Refer to fig. 3.
Fig.3
To Boiler
TERMINATIONS
Air inlet terminals must be facing horizontally or downwards to
prevent entry of rain into the terminal and positioned to ensure
only fresh air is drawn into the boiler. The air terminal must be
located outside of the building. Flue terminals must be
positioned so that flue products are not drawn into the air inlet.
Site specific wind conditions should be considered to achieve
this. Drawing of combustion air directly from a ventilated boiler
room invalidates the heat exchanger warranty.
The flue outlet terminal is designed to face outwards and must
not be directed in the region of the air inlet. The flue terminal
and air inlet terminal can be located on different, but not
opposing wall faces.
The two terminals are subject to the requirements of BS 5440
Pt 1 for clearances from features of the building although some
can be decreased to the values indicated.
The Keston 30C, as with any condensing boiler, will generate a
condensate "plume" from the flue terminal in all weather
conditions. Consideration must therefore be given to the effect
of this "plume" when selecting a location for the flue terminal. It
is the responsibility of the installer to ensure the selected
terminal location does not cause nuisance.
If either the air inlet or flue outlet terminate at a height of less
than 2.1m above ground level, the terminal must be protected
by a suitable guard. The K6 terminal guard (with plastic
coating), manufactured by Tower Flue Components Ltd is
suitable for this purpose.
18
INSTALLATION
Tee Fitting
6 in min.
Dimensions (mm)
A Below, above or beside openable window, air
brick, etc.
B Below gutters, soil pipes, drain pipes.
C Below eaves.
D Below balconies or car port roof (lowest point).
E From vertical drain or soil pipes.
F From internal or external corner or to a
boundary alongside the terminal. *
G Above ground or balcony or roof.
H From surface or boundary facing a terminal. *
I From terminal facing a terminal.
J From opening in a car port.(not recommended)
K Vertically from terminal on same wall.
L Horizontally from terminal on same wall.
*The dimensions given in the table above may need to be
increased to avoid wall staining and nuisance depending on
site conditions.
CLEARANCES FROM WALL
Flue outlet and air inlet terminations must be at least 40mm
from the wall face.
DISTANCE BETWEEN FLUE OUTLET & AIR
INLET
There is no maximum - the terminations must not be on
opposite sides of the dwelling but can be in areas of unequal
pressure.
A minimum clearance of at least 500mm must be left between
the terminations otherwise a 90º elbow MUST be fitted to air
inlet and pointed towards the ground. The absolute minimum
clearance between the flue and air terminals is 100mm.
GENERAL INSTALLATIONS
All parts of the system must be constructed in accordance with
BS 5440 Part 1, except where specifically mentioned in these
instructions.
All pipework must be adequately supported.
All joints other than approved push-on or plastic compression
connectors must be made and sealed with solvent cement
suitable for muPVC pipes and conforming to BS 6209: 1982.
Consideration must be given to Corgi/Gas Safe bulletin TB200/
TB008 regarding flues in voids.
The boiler casing must always be correctly fitted to the boiler
when leaving the appliance operational.
External wall faces and any internal faces of cavity walls must
be good.
Rubber collars are available for flue and air terminals to finish
the external wall face around the terminals (Part No
C.08.00.07.0).

AIR SUPPLY

The Keston 30C is a room sealed appliance and therefore
does not require purpose provided ventilation to the boiler room
for combustion air.

COMPARTMENT INSTALLATION

Due to the low casing temperatures generated by the boiler, no
compartment ventilation is required. However, the cupboard or
compartment must not be used for storage.
Keston 30C -
Flue Air
Terminal Inlet
300 50
75 75
200 50
200 50
75 50
200 50
300 100
600 100
1,200 1,200
1,200 100
1,500 1,500
300 300
Installation and Servicing