Webasto Thermo Pro 90 D, Installation Manual

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www.webasto.us 37 Webasto Thermo & Comfort N.A., Inc.
Thermo Pro 90 Troubleshooting
14. Troubleshooting
14.1 General Information
The control unit continuously monitors the heater operation. The control unit identifies errors on individual heater
components and faults during operation. Should the control unit experience component errors and operational faults,
the heater will be shut down.
14.2 Heater Interlock
Fuel is supplied for a max. of 240 seconds if the flame does not start.
Fuel is supplied for a max. of 240 seconds if the flame goes out during operation.
The fuel supply is shut off if the system overheats (temperature limiter is tripped). If the system overheats the
temperature limiter will reset itself after a cool down period.
If the under-voltage protection switches the system off for longer than 20 seconds, the fuel supply is interrupted and
the heater switches OFF.
NOTE:
The heater does not automatically switch back ON. The heater will need to be switched OFF and back ON to re-start
after a fault.
14.2.1 Heater Lock out Reset Procedure
Heater Lock out Reset Procedure:
1. Using switch or standard timer control, turn heater on
2. Remove the main power connection to heater from battery or pull fuse for a minimum of 20 seconds.
3. Using switch or standard timer control, turn the heater off.
4. Reinstall main heater power connection where previously disconnected.
Rectify the cause of the fault.
IMPORTANT: Heater fault codes can be read using PC Diagnostics, however, the heater lockout reset must be
manually performed using the procedure stated above.
14.3 Diagnostic after a Fault Lock-out for the Thermo Pro 90
Check the fuses and plug connectors.
14.3.1 Version with switch
If the system is operated with a switch, the nature of the fault is indicated by a flashing code on an indicator light
(toggle of switch) during the run-on time of the heater.
After five short signals, count the long flashes:
1x No start (after 2 attempts to start)
2x Flame failure
3x Under-voltage or over-voltage
Thermo Pro 90
12 Volt 10.V – 0.5V
24 Volt 21V – 1V