Filter Replacement Light
Coway Air Purifier
Severity: MinorWhat Does This Error Mean?
Coway lights the filter replacement indicator when the HEPA filter timer expires — typically 12 months at normal use.
The unit keeps running.
The fix is to replace the HEPA filter, replace the carbon pre-filter (if used), and reset the indicator with a long-press of the Filter Reset button.
The reset returns the timer to zero for a fresh 12-month cycle.
Affected Models
- Coway AP-1512HH (Mighty)
- Coway Airmega 200M
- Coway Airmega 250
- Coway Airmega 400
- Coway AP-1216L (Tower Mighty)
- Coway Airmega ProX
Common Causes
- HEPA filter timer reached the 12-month replacement interval
- Filter never changed since purchase
- Counter not reset after the previous swap
- Heavy use in high-pollution conditions loading the filter early
How to Fix It
-
Order the correct HEPA filter.
Match the model name on the back of the unit.
Coway sells genuine HEPA + carbon combo packs for 35-80 USD.
Aftermarket filters fit the AP-1512HH and Airmega 200M well; less consistent on premium models like Airmega 400. -
Power off and unplug.
Switch the unit off and pull the plug.
Wait for the fan to fully stop. -
Open the back panel.
On the AP-1512HH, the back panel pops off with a finger pull.
On Airmega 200M and similar, gently squeeze the sides and lift.
The filters are stacked: pre-filter outside, carbon layer, HEPA layer behind. -
Wash the pre-filter.
The first layer is a washable pre-filter (the mesh).
Rinse with warm water, let air dry overnight before reinstalling.
This is the only Coway layer that is reusable; carbon and HEPA must be replaced. -
Swap carbon and HEPA layers.
Pull the old carbon and HEPA filters out.
Insert the new filters in the same order.
On Airmega models, follow the printed orientation arrow.
Wrong order does not damage anything but reduces filtration. -
Reinstall the back panel.
Press the panel back on until it clicks evenly along the edges.
A loose panel makes airflow noisy and lets unfiltered air leak around the filters. -
Reset the filter light.
Hold the Filter Reset button for 3-5 seconds (some Airmega models say 'Reset' next to the button).
The light goes out.
The 12-month timer starts fresh.
If the light stays on, hold longer — some Airmega Pro models need 5 full seconds.
Frequently Asked Questions
Why does the light come back on the next day?
The reset did not register — usually because the button was not held long enough.
Hold for the full 3-5 seconds, watching the light go out and stay out.
Then turn the unit off and back on; if the light is still off, the reset succeeded.