Webasto Heater Service Repair Manuals

1. Air intake

2. Air blower

3. Outlet fluid pipe

4. Incandescent pin / flame sensor

5. Evaporative pad

6. Sealed connector

7. Control unit with temperature sensors

8. Heat exchanger

9. Combustion chamber

10. Exit exhaust

11. Fuel pipe

12. The circulation pump

13. Intake fluid pipe

14. Fuel metering pump

Thermo E Series Heater Lock Release

To unlock, proceed as follows.


1. Turn on the heater with a regular control. 1. Turn on the heater with a regular control.

2. Disconnect the power cable, for example by removing the appropriate


3. Disconnect the control wire.

4. Pause for about 30 seconds.

5. Connect the power wire.

6. Connect the control wire.


In case of repeated blocking of the heater, the equipment is subject to

Service staff trained by Webasto-Spheros.

Release lock, error code F12, for Thermo E series heaters

A- The heater is turned on - the indicator lamp shows error code 12.

B- Remove the fuse at 25A with the heater turned on.

B- Turn off the heater.

G- Insert the 25A fuse into place.

D- Turn on the heater- lock is removed.

Adobe Acrobat Document 3.5 MB
Webasto HL18 Air Top 18 Workshop Manual.
Adobe Acrobat Document 5.5 MB
Adobe Acrobat Document 254.0 KB
Webasto Heater HL125 Workshop Service Ma
Adobe Acrobat Document 6.2 MB

Wiring diagram

Webasto liquid pre-heaters (liquid autonomous heaters) of the Thermo 50 series work independently of the car engine and, in combination with a standard car heating system (with liquid cooling) or as part of a separate

heating systems, are used for:

  • prestarting (before starting the engine) warming up the car engine and, if necessary,

to cover the heat deficit of the car engine during its operation.

  • prestarting (before starting the engine) warming up the vehicle interior,
  • defrosting car windows,


Liquid heaters are connected to the cooling system (cooling circuit),

fuel system and vehicle electrical system.

Suitable fuels are those prescribed by the vehicle manufacturer.

These heaters when switching from summer to winter diesel fuel must be run on

15 min to fill pipelines and fuel pump with new fuel. Additives to fuel do not have a harmful effect on the operation of the heater.

Comments: 0