Technical data

HL 90
40
7 Combustion air supply
Under no circumstances may the combustion air be taken from areas occu-
pied by people. The combustion air intake opening must not point in the di-
rection of travel. It must be located so that it cannot become clogged with
dirt or snow and cannot suck in splashing water.
The combustion air intake line (internal diameter min. 30 mm) may be up to
5 m in length and contain several bends totalling 360°. The minimum bend-
ing radius is 45 mm.
NOTE:
If the combustion air intake line cannot be installed so that it slopes down-
wards, a water drain hole with a diameter of 4 mm is to be made at its low-
est point.
If the heater is installed in a general installation space near the vehicle’s fuel
tank, the combustion air must be taken in from the outside and the exhaust
fumes discharged into the atmosphere. The openings must be splash-proof.
A ventilation opening measuring at least 10 cm
2
is required if the heater is
installed in an enclosed box. The size of the ventilation opening must be in-
creased subject to consultation with Webasto if the temperature in the box
exceeds the permitted ambient temperature of the heater (see Technical da-
ta).
7.1. Intake silencer
It is recommended for the intake silencer (order no. 198 56A) to be installed
in order to reduce intake air noise (Figure 10). This is placed on the intake
manifold.
Figure 10: Intake silencer
7.2. Combustion air intake line
Length of combustion air intake line
With silencer: max. 3 m
Without silencer: max. 5 m
Internal diameter of the lines: 30 mm
Minimum bending radius: 45 mm
Total bends: max. 360°
HL90 EA_de_en_fr.book Page 40 Wednesday, June 5, 2013 10:17 AM