Your Portable Control Unit (PCU) will display the message "CHG FIL" (which appears as "CH6 FIL") accompanied by a blinking red light.
The CHG FIL message is simply an automatic reminder indicating "Change Filter".
The unit does not have the ability to test the quality of the filter so the act of changing the filter will not dismiss the message.
We recommend cleaning the filter weekly and replacing it with a brand new filter every 2-4 weeks as per the manufacturer recommended changing schedule.
If changing is not yet required, you can dismiss the reminder by holding the "Filter" button for 5 seconds (10 max).
If you require any further assistance, please contact Customer Service.