Indoor unit's impeller/motor coupling bolt head broken

[vikky1971]

Dear all,
In my absence my Air con(1Ton)was serviced, after four months when I opened the indoor unit, found that the motor-impeller coupling bolt head has broken. I sprayed WD-40 to ease it up but no use. Due to this hurdle the vanes of the impeller can't be cleaned properly. Can someone give a practical solution to this?

[monkey spanners]

Has the bolt head definitely broken off, many fans are held on with grub screws which look a bit like a bolt with a missing head.
Could you clean the fan with compressed air in place instead of removing it?

[vikky1971]

@monkey spanners I had dismantled the impeller of this hitachi indoor unit. There is no grub screw. As per your advice I will use the compressed air and nylon brush to remove the dust accumulated on the vanes.