Operating instructions

4. Installation
4.1 General Information
Webasto will take you step by step through the installation process to ensure successful operation
for years to come. The installation must be performed in accordance with the installation instructions
provided in this manual.
4.2 Installation Locations
Fig. 401: Installation Locations
1. Behind cab or sleeper.
2. On left/right side of the frame.
3. In an existing enclosure (tool box) on the vehicle.
The Thermo 90 S should be installed as low as possible in the cooling system to assure static
bleeding of the heater and the circulating pump.
401
Thermo 90 S 4 Installation
NOTE:
This manual does not cover all possible installations. For special applications use this manual as a
general guideline only. Contact an authorized Webasto dealer or Webasto Thermosystems directly
at USA: 1-800-555-4518 Canada: 1-800-667-8900
WARNING
The heater must not be installed in either the driver’s compartment or in the passenger area of
vehicles.
NOTE
The circulating pump is not self priming.