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WEBASTO DBW SERIES HEATERS MAINTENANCE
Maintenance of the Heater
To ensure functional reliability of the heater the following maintenance must be performed:
• check combustion air inlet and exhaust outlet for contamination and clean as required.
• outside the heating season the heater should be operated with the vehicle engine cold approximately every four
weeks for 10 minutes setting the heating system to "warm" and opening all appropriate coolant flow control
valves. This avoids difficulties in the startup at the beginning of the heating season and prolongs heater motor
and bearing life.
• after replacing the coolant of the vehicle engine ensure proper bleeding of the heater after bleeding the vehicle
cooling system. Start the vehicle engine and turn OEM heater system on in full heat mode. Switch on heater
circulation pump (if separate switch is available) or operate heater for 5 seconds to run circulation pump using
rundown cycle. Repeat procedure as required until warm air comes out of heating ducts. Replenish coolant to
manufacturer's instructions if level is low.
• before the heating season (point of time when weather conditions cause increased use of equipment) the fuel
filter or filter cartridge must be replaced to prevent malfunctions.
• the heater should be checked on regular intervals by a Webasto service agent, the latest before the beginning of
the heating season.
