Yamaha Professional Serie Mode D'emploi page 12

CLEANING THE FAN FILTER ELEMENTS
1. Make sure the power to the amplifier is OFF.
2. Remove the power plug from the AC mains socket.
3. Use the supplied 3mm Allen key (hex wrench) to remove
the four hex bolts securing the front filter grilles.
4. Remove the filter elements, and wash in plain water. If
the filter elements are exceptionally dirty, detergent
(washing-up liquid) may be used.
5. Dry the filter elements thoroughly. NEVER REPLACE
THE FILTER ELEMENTS WHILE THEY ARE STILL
WET!
Replace the elements and front filter grilles. (The re¬
placement part number of the filter element is Vi 31380.)
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