Komatsu PC220LC -8 Operation & Maintenance Manual page 130

OPERATION
DETAILED CONTROLS AND GAUGES
Large Capacity Airflow Air Conditioner Blower Switch
(If equipped)
When this switch (12) is pressed, the additional blower motor is
actuated and the air flow from the air conditioner vents increases.
(a) ON: Large-capacity air conditioner blower is actuated
(b) OFF: Large-capacity air conditioner blower is stopped
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