Fuel Supply - Webasto Air Top Evo 3900 Workshop Manual

8 Servicing work
If this value is exceeded the heat output may be reduced
as a result of the hot air outlet temperature control.
The heater can be used with grates on the air inlet and
outlet side if it is used in an air circulation system.Do not
short circuit the current of hot air.
Minimum internal diameter of the main section of hot air
line:
80 mm for the Air Top Evo 3900
90 mm for the Air Top Evo 5500
The hot air hose must be secured at its connection points.
IMPORTANT
In vehicles used to transport people, the air outlet opening
is to be directed in such a way that it is at least 20 cm away
from all body parts.
The heaters check the internal temperature rise
automatically each time they are switched on. If this is
above the specified limits, the start is cancelled and error
messages F10 is displayed. To ensure that the heater
functions stably, the flow resistance of the connected hot
air system must be reduced.
If a filter is used for the hot air, it must have the following
properties:
• The current of air must not carry any inflammable and/
or harmful fibres or particles into the heater or the
interior of the vehicle.
• The filter material must be able to withstand
temperatures of at least 60 °C
• The filter must be resistant to all the substances that
may be drawn in with the hot air (for example
moisture, salt, fuel vapours, etc.).
• The resistance of the filter must be taken into
consideration when designing the hot air system
802
Air Top Evo 3900/5500

8.6.2 Fuel supply

The fuel is taken from the vehicle fuel tank or from a
separate fuel tank. The values for the maximum pressure
at the fuel extraction point are shown in Figure 801.
Permissible fuel inflow
height H (m)
0.00
1.00
2.00
Maximum fuel intake
height S (m)
0.00
0.50
1.00
At max. perm. pressure
(bar) in fuel line
0,20
0.11
0.03
At max. perm. negative
pressure (bar) in the fuel
tank
-0.10
-0.06
-0.02