Philips humidifier displays CF or a filter icon and may beep; the unit still runs but requests maintenance.

Safety: Turn off and unplug the humidifier before removing filters.

• Remove filter: Open the filter compartment and remove the Philips humidifier wick or cartridge.
• Inspect and clean/replace: If the filter is heavily discolored, slimy, or has an odor, replace it with a genuine Philips replacement filter. Some wicks can be rinsed under running water to remove loose debris, but always follow the Philips manual for your specific model.
• Reset indicator: After replacing or cleaning, reset the filter reminder according to the user manual (this often involves holding a specific button for several seconds).

Using non-genuine filters can affect performance and may not clear the reminder properly.