Philips AC4074 User Manual page 16

ENGLISH
16
Filter replacement lights
The filter replacement lights indicate which filter has to be cleaned or
replaced.
- Filter replacement light 1 flashes: filter 1 (the pre-filter) has to be
cleaned. See chapter 'Cleaning' for further instructions.
- Filter replacement light 2 flashes: filter 2 (the formaldehyde filter
(supplied with AC4074) or multi-care filter (supplied with AC4072))
has to be replaced.
- Filter replacement light 3/4 flashes: the activated carbon filter and the
HEPA filter have to be replaced.
Note: The HEPA filter and the activated carbon filter have a similar lifetime.
Therefore they have to be replaced at the same time.
Filter replacement lock
If you do not replace the filter in time, the appliance stops operating
approx. 2 weeks after the filter replacement light started flashing.When the
appliance is locked, it does not operate until you have replaced the full filter
and pressed the reset button.
Note: When filter replacement lights 2 or 3/4 and REPLACE FILTER on the
control panel are on continuously, the appliance is locked (see section 'Filter
maintenance' in this chapter for more information).
How long it takes before the appliance is locked depends on the operating
time and speed level selected after the filter replacement alert.
Approximately 1 day before the appliance locks, it beeps every 30 minutes
to inform you that one of the filters needs to be replaced.
When the appliance is locked, you hear a beep when you press any button.
You can switch off the appliance by pressing the on/off button.
If the appliance is locked:
1 Check which filter needs to be replaced (see section 'Filter
replacement alerts').
2 Switch off the appliance and unplug it.
3 Replace the appropriate filter (see section 'Replacing the filters').