There are some possible reasons caused, please check below first:

 

<Airflow>

 

     Air Flow is important for cooling:

 

  1. Please make sure the intake and exhaust vents are free from obstruction.
  2. Make sure the projector is not enclosed or right against a wall - it needs ventilation space.
  3. Don’t place the projector on top of other electronic equipment, such as an AV receiver.

 

<High Altitude>

 

If the projector is being used in higher altitude you will need to turn on the “High Altitude” mode. The fan will thus operate at a higher speed to intake more air. Please check user guide to enable it.

 

If above steps don’t help, please contact ViewSonic service center.