An air purifier is a fan and a set of filters, and nearly everything that goes wrong with an LG PuriCare is about one or the other. The unit has no water, no heater and no refrigerant, which makes it one of the few LG appliances where the owner can address most complaints alone. The exceptions are a fan motor and a control board, and both announce themselves clearly.
The Filter Indicator Is a Timer
The filter replacement light comes on after a set number of running hours, not because the unit has measured the filter. It is a reminder based on typical use, and in a dusty home or one with pets the filter may be exhausted before the light appears, while in a clean bedroom it may have life left when it does. Reset the indicator after a filter change by holding the button the manual names; if the light is not reset it will come on again at the wrong time and mislead you.
Which Filter Does What
PuriCare models stack a washable pre-filter that catches hair and large dust, a fine particle filter, and a deodorising filter for odours and gases. The pre-filter is cleaned, not replaced: with the unit switched off and unplugged, remove the cover, lift the pre-filter out, vacuum or rinse it and let it dry completely before refitting. The particle and deodorising filters are replaced. A unit bought new that seems to move no air at all has usually been run with the plastic wrap still on the filters; check that first.
The Air Quality Light Stuck on Red
The colour ring shows what the dust sensor is reading, and a sensor with a dusty lens reads poor air forever. The sensor is a small window on the side or back of the unit behind a cover that lifts or slides. With the unit unplugged, open it and wipe the lens gently with a dry cotton swab, then close it and restore power. The reading should settle within a few minutes. Do not spray anything into the sensor. A sensor that reads red in visibly clean air after cleaning, or that never changes at all, has failed and is a technician part.
Weak Airflow
If the fan runs but little air comes out, the filters are loaded or the pre-filter is matted. Replace or clean as above. Make sure the intake and outlet are not against a wall or curtain; the manual gives the clearance. If airflow is weak with new filters fitted correctly, the fan motor is losing speed.
Sounds
A faint whir is normal and rises with the fan speed. A rattle is usually a filter cover not clicked home or a filter sitting crooked. A grinding or squeal that follows fan speed is the motor bearing, which is a repair, not a filter.
Odour From the Unit
A purifier that smells is exhaling what its deodorising filter has absorbed and can no longer hold. Replace it. Running the unit in a room where cooking or smoking is heavy shortens the life of that filter far below the indicator timer.
When to Book
A fan that will not start, a motor that grinds, a control panel that ignores touch, or a sensor that stays red after cleaning are the cases for an LG air purifier repair. Give the model number from the plate on the base or back, which filters were changed and when, and what the air quality light does.