the bad news is that with this an most of the other methods the dust and dirt will just be in the plenum chamber waiting to be blown back intot he holes later.
Maybe put a shop vac where the motors normally blow into and try and suck the dust out of the plenum as you blow the air nozzle into the holes.
Maybe put a shop vac where the motors normally blow into and try and suck the dust out of the plenum as you blow the air nozzle into the holes.

LCHIEN
Loring in Katy, TX USA
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