Bosch WORCESTER Greenstar Heatslave II 12/18 Installation, Commissioning And Servicing Instruction Manual page 19

To provide sufficient air a suitable inlet must be provided into the room
or space in which the boiler is situated.
Output 12/18
2
Size cm 99
An air brick or other form of continuous air supply may have to be built
into the installation in order to ensure an adequate supply of air.
If the appliance is to be installed in a confined space or compartment two
air vents are required, one at high level and one at low level.
The minimum free area of each vent is shown in table 4 and depends
whether the air is taken from another room or from outside the building.
Where the air is taken from another room that room must contain an air
inlet as described above.
Room sealed flue (RS)
The appliance does not require a separate vent for combustion air.
Installation in cupboards or compartments require permanent vents for
cooling purposes, one at high level and one at low level, either direct to
outside air or to a room.
Both vents must pass to the same room or be on the same wall to the
outside air.
The minimum air vent free area is given in table 5.
Installation clearances
Figure 20 shows the minimum space recommended to install the boiler
only.
0 m m
1 2 0
m m
6 0 0
1 0 0
m m
7 2 0
m m
Fig. 20 Installation clearances
Service clearances
Figure 21 shows the minimum space required to carry out an annual
service.
* Remove the flue "knock-out" panel sections if this clearance is less than
75mm.
The appliance is suitable for an under worktop installation providing that
the worktop above the boiler (min 10mm clearance) is removable for
maintenance and repair and the front of the boiler is not enclosed.
0 m m
1 2 0
m m
6 0 0
5 m m
*
5 3 0
m m
Fig. 21 Service clearances
Greenstar Heatslave II 2022 + 6 721 843 978 (2022/01)
18/25 25/32
138 165
3 0 0
m m
1 0 0
m m
1 0 m
m
5 m m
*
Maintenance clearances
Figure 22 shows the clearances required for maintenance.
* Remove the flue "knock-out" panel sections if this clearance is less than
75mm.
0 m m
1 2 0
m m
6 0 0
5 m m
*
5 3 0
m m
Fig. 22 Maintenance and repair clearances
3
Minimum air vent area (cm ) for appliances installed in
compartments
Internal ventilation
Model High level Low level
12/18 198 297
18/25 275 413
25/32 330 495
Table 4 Conventional flue
Internal ventilation
Model High level Low level
12/18 198 198
18/25 275 275
25/32 330 330
Table 5 Room sealed flue
Compartments
Follow the requirements of BS 5410 and note:
Minimum clearances must be maintained.
An access door is required to install, service and maintain the boiler and
any ancillary equipment.
If fitting the boiler into an airing cupboard use a non-combustible
material (if perforated, maximum hole sizes of 13mm) to separate the
boiler from the airing space.
Venting compartments
There must be sufficient clearance around the appliance to allow proper
circulation of ventilation air. The clearances required for installation and
servicing will normally be adequate for ventilation.
Ventilation must be provided for boilers fitted into compartments as
described in BS 5410.
Combustion air must not be taken from a room or internal space
containing a bath or shower and must not communicate with a protected
area such as a hall, stairway, landing, corridor, lobby, shaft etc.
Air vents must allow access for clean free air and must be sited to comply
with the flue terminal position requirements.
Air duct runs must not exceed 3 m.
Low level air vents must be less than 450mm from the floor.
A warning label must be added to the vents with a statement to the
effect: "Do not block this vent. Do not use for storage".
Pre-Installation
3 0 0
m m
5 m m
*
External ventilation
High level Low level
99 198
138 275
165 330
External ventilation
High level Low level
99 99
138 138
165 165
19