Denso RC7M Manual page 110

Step 3 Blow compressed air to the filter in the direction opposite to the regular air- flow.
Note: Use dehumidified, oil-free, pure compressed air for cleaning.
If the filter is excessively dirty, wash it with water or warm water (40°C or lower). A
neutral detergent is most effective.
Notes (1) Dry the washed filter completely before mounting it.
(2) If the filter is still dirty after air blowing or washing, replace it
Step 4 Set the filters back into place in the reverse order of removal.
with new one.
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