Combustion Air Supply - Webasto Thermo 90 ST B Installation Manual

Thermo 90 ST

9. Combustion Air Supply

Under no circumstances may the combustion air be
taken from areas occupied by people. The combustion
air intake opening must not point in the direction of
travel. It must be located in that it cannot become
clogged with dirt or snow and cannot suck in splashing
water.
IMPORTANT!
The combustion air must be extracted using
a combustion air line from a position that is
as cool as possible and protected from
splashing water.
The combustion air intake line (internal diameter at least
30 mm) may be 0.5 m to 5 m (1.6 ft to 16 ft) long with
several bends totalling 360°. The minimum bending
radius is 45 mm (1.75 inches).
The combustion air intake must not be routed above the
exhaust outlet.
IMPORTANT!
If the combustion air intake line cannot be
installed so that it slopes downwards, a
water drain hole with a diameter of 4 mm
(5/32") is to be made at its lowest 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 6 cm² (1 inch²)
is required if the heater is installed in an enclosed box.
The size of the ventilation opening must be increased
accordingly if the temperature in the box exceeds the
permitted ambient temperature of the heater (see
Technical data).
www.webasto.us
Combustion Air Supply
21 Webasto Product N.A., Inc.