You installed a new filter, and the replace-filter light is still on. On most purifiers that light is a countdown based on running hours, so it does not know the filter has been changed until you tell it.
Before You Open the Filter Door
Switch the purifier off and unplug it before removing or installing filters.
Steps That Usually Fix It
- Remove all packaging: new filters often come in plastic bags that must be removed before use.
- Check the filter type and direction: use the filter listed for your model and install it facing the way the airflow arrow or manual shows.
- Close the filter door fully: some models will not run properly if the door or cover is not seated.
- Reset the reminder: plug the unit back in and use the reset button or button combination from your owner’s manual. On app-connected models, the reset may also be available in the app.
If the Light Will Not Clear
If the reset steps do not work, the control panel or board may be at fault. Check the manufacturer’s warranty first, then book an air purifier repair diagnosis if needed.