Coway Airmega 300 (AP-1515H): problems, parts and running costs
Checked: 2026-10-14
Summary
The Airmega 300 is a 21.4 lb large-room purifier that covers 2,512 sq ft at one air change per hour and about 1,256 sq ft at two. What owners search for most after buying is the filter: the Max2 set costs about $99 a year and is the single most common complaint. Coway lists it at $549 direct and Consumer Reports from $449.99; at around $450-500 it is competitive, above $600 it is not.
Common problems and fixes
- Expensive replacement filters — the top complaint across owner communities: “high cost of replacement filters” on the 300S and “expensive replacement filters” on the 300. Budget about $99 a year for the Max2 set; the filter light tracks usage rather than the calendar, and Coway states 6-12 months of life. [4][5][1][10]
- Weak gas and VOC removal — “ineffective at removing VOCs” is a top owner con; the carbon layer is thinner than dedicated gas units, so particle performance is the strength, not gas. If smoke odors or gases are the main problem, look at a unit with a heavier carbon stage. [5]
- No casters — the 21.4 lb unit is awkward to move between rooms; decide where it lives before you buy. [8]
Parts and consumables
- Max2 filter set (activated carbon and Green True HEPA in one unit) — $99 from the Coway US store, checked 2026-10; Consumer Reports estimates the same $99 a year. The whole set is replaced even when only one layer is spent, about every 12 months. [7][1][2]
- Washable pre-filter — cleaned periodically rather than replaced. [1][3]
Yearly running cost
Consumer Reports estimates $99 a year for the Max2 filter and $17 a year for electricity, roughly $116 a year in consumables and energy combined. That is the dominant ownership cost; there are no other consumables.
When it is a good buy
- Coway’s US store lists the Airmega 300 at $549 (price checked 2026-10); Consumer Reports lists it from $449.99. A $362.25 sale on Coway’s homepage was marked sold out at the time of check. [1][2][12]
- At about $450-500: competitive for a large-room unit with a 5-year warranty and proven particle filtration; the filter cost is the tradeoff. [2][10]
- At $549 direct: a premium over Consumer Reports’ street price; compare the 300S with Wi-Fi or the Airmega 400 before deciding. [2][8]
- Above $600: weak value; the Airmega 400 offers more coverage and has been independently tested at a similar or lower price. [9][13]