A projector in a conference room has been shutting down randomly during meetings. You've checked the operational hours for the bulb and they remain well within it's lifespan. You have also verified the seating and integrity of the bulb. You hear the whir of the fan from the projector from several feet away, but no grinding or knocking. There are no power-saving settings turned on. There are heat-warnings visible on the interface. You suspect that you may need to replace:
The dust filter
The whole projector
Replace the fan
The bulb