Technical data

Thermo 90 S / Thermo 90 ST Connection to the vehicle cooling system
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5 Connection to the vehicle cooling system
In thermostat circuits, only use thermostats which start to open
at < 65 °C.
The heater is connected to the vehicle cooling system as shown in
Figure 2. The system must contain at least 6 litres of coolant.
The water hoses supplied by Webasto must always be used. If you do
not use these hoses, the hoses that you do use must comply with DIN
73411. The hoses must be installed without kinks
and (to ensure perfect
bleeding) rising if possible. Hose connections must be supported by
hose clips to prevent them slipping.
NOTE:
The hose clips must be tightened with a torque of 4 Nm.
The cooling system must be bled carefully before using the heater for
the first time or after replacing the coolant. The heater and lines should
be installed in such a way as to ensure static bleeding.
Perfect ventilation can be identified by the circulating pump operating
almost silently.