Webasto HL 90 Notice D'utilisation Et D'entretien page 24

Operation of the heater
The air heater can be started using a switch, a mechanical cabin thermostat or
a digital timer, according to its equipment.
GB
General
The time when heating starts can be programmed using the digital timer within
a time range from 1 minute to 23 hours 59 minutes.
The on-time can be 59 or 29 minutes starting from the programmed time or after
"immediate heating" is pressed.
Continuous operation is also possible after pressing the "immediate heating"
button, if the unit is connected accordingly.
Operation
The heater switches off automatically after a short run-on time when the ignition
is switched off.
Switching on
Manual: Press the immediate heating button .
Automatic: By programming the start of heating.
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