NEC NP-PH1400U User Manual page 207

2. Remove the filter.
Pull the top of the filter outward and remove the filter by lifting
it up.
3. Install the new filter.
Insert the filter with "↓ AIR FLOW ↓" facing the projector.
(1)Insert the filter in the flange.
(2) Fit the top edge of the filter in the inlet.
4. Place the filter cover back onto the projector cabinet.
(1)Insert the guide pin (4 locations) of the projector into the
notch (4 locations) of the filter cover.
(2)Slide the filter cover to the right and tighten each of the
two knobs by turning them clockwise.
NOTE:
Be sure to clean both filters (left and front sides) to display the filter
usage hours as accurate as possible.
Guide pin
193
7. Maintenance
Filter
2
1
Flange
Notch