ARemove the board fixing plate clamping screws (two PTT screws 4 x 16, indicated by ●).
BRemove the light emitting board (bottom) from the board fixing plate, and disconnect the lead wires.
(8) Light receiving board
1Perform the same work as in steps 1 through B of (7) above.
2Reverse the main body, remove the clamping screws (twelve special black screws 4 x 16, indicated by ●) from the rear surface, and then reverse the main body back to the original position again.
3Remove the panel (center).
4Remove the duct
