Flue Terminal Positions; Air Supply - Bosch Worcester 15SBi Installation And Servicing Instructions

5. Flue terminal positions

The flue system must be installed following the requirements of
BS5440:1.
The standard flue kit length is 425 - 725mm. Extension kits for
flues up to 4m are available.
The terminal must not cause an obstruction nor the combustion
products a nuisance.
If the terminal is within 1m of a plastic or painted gutter or
within 500mm of painted eaves then an aluminium shield at
least 750mm long should be fitted to the underside of the gutter
or painted surface.
If the terminal is less than 2m above a surface to which people
have access then a guard must be fitted. The guard must be
evenly spaced about the terminal and fixed with plated screws.
A guard Type K2 can be obtained from Tower Flue Components,
Vale Rise, Tonbridge, TN9 1TB.
It is essential that products of combustion cannot re-enter the
building. Refer to Fig 4.
Fig. 4. Siting of the flue terminal.
A
G
D
HI
TERMINAL POSITION
A– directly below an openable window or
other opening e.g. air brick.
B– Below gutters, soil pipes or drain pipes.
C– Below eaves.
D– Below balconies or car port roof.
E– From vertical drain pipes and soil pipes.
F– From internal or external corners.
G– Above ground, roof or balcony level.
H– From a surface facing a terminal.
B,C
A
M
F J E
MIN. DISTANCE
300mm
300mm
600mm
A separate vent for combustion air is not required.
If the appliance is in a cupboard or compartment it is not
necessary to have additional ventilation for the boiler
providing that the following clearances are provided:
Above the flue turret
In front*
Below
Right-hand side
Left-hand side
* Clearance to a removable panel i.e. door.
If the appliance is installed in a cupboard or compartment that
does not allow these clearances then permanent air vents are
required in the compartment, one at a high level and one at a
low level. Both high and low level air vents must communicate
with the same room or must both be on the same wall to the
outside air. The minimum requirements are:
Model Position of vent
24SBi
15SBi
F
G
TERMINAL POSITION
I– From a terminal facing a terminal
J– From an opening in a car port (e.g. door
75mm window) into dwelling.
25mm K– Vertically from a terminal on the same
25mm wall.
25mm L– Horizontally from a terminal on the same
25mm wall.
M– From door, window or air vent (achieve
where possible).
7

6. Air Supply

Air from room
High 315cm 2
2
Low 315cm
High 315cm 2
Low 315cm 2
L
K
L
K
F
MIN. DISTANCE
1200mm
1200mm
1500mm
300mm
300mm
30mm
250 mm
200mm
75 mm
75mm
Air from outside
158cm 2
2
158cm
158cm 2
158cm 2