The Webasto Thermo 90 90S Coolant Heater Complete Workshop Service Repair Manual is your comprehensive guide to servicing and repairing your Webasto heating system. This manual covers all models, engines, trim levels, and transmission types, ensuring that you have the information you need to handle any repair or maintenance task. The manual is organized in a clear and concise manner, providing detailed step-by-step instructions with accompanying illustrations for every procedure. From basic maintenance tasks to complex repairs, this manual has you covered. You will find information on troubleshooting, diagnostics, component replacement, and much more. This manual will empower you to confidently tackle any repair or service need, saving you time and money in the long run.

The Webasto Thermo 90 and 90S Coolant Heaters are highly regarded auxiliary heating systems designed for use in various automotive applications. These compact and efficient heaters are renowned for their ability to preheat the engine coolant, ensuring a comfortable cabin temperature and improved fuel economy, particularly in cold weather conditions. The Thermo 90 and 90S models are both characterized by their robust construction, incorporating durable materials and precise engineering for reliable performance. They are known for their quiet operation and minimal fuel consumption, making them a popular choice for vehicle owners seeking enhanced comfort and efficiency. The Thermo 90 and 90S heaters function by utilizing a compact combustion chamber where fuel is burned to generate heat. This heat is then transferred to a heat exchanger, which in turn warms the engine coolant. The warmed coolant circulates through the engine and the vehicle's heating system, providing a comfortable cabin temperature even when the engine is cold. The Thermo 90 and 90S are equipped with various safety features, including a flame sensor, a pressure sensor, and a thermal cutout switch, ensuring safe and reliable operation. The Thermo 90 and 90S heaters are designed for easy installation and maintenance, with a comprehensive workshop service and repair manual available to assist technicians in ensuring optimal performance and longevity.