Coway Airmega 250S review

The Coway Airmega 250S is the connected sibling of the non-Wi-Fi Airmega 250. The practical difference is not a larger room rating: Coway publishes the same 930 square feet at two air changes per hour and 465 at four for both. The 250S adds Wi-Fi, the IoCare+ app, app scheduling and a manufacturer-listed voice-control option while retaining the same front-access filter arrangement and physical controls. It is best for someone who will actually use remote management in a medium room, not for a shopper expecting the “S” to raise the purifier’s airflow rating.

The same room plan as the non-Wi-Fi 250

Coway gives the 250S 1,860 square feet at one air change per hour, 930 at two and 465 at four. Rescaling 465 at four changes per hour to the site’s 4.8-ACH comparison gives a conservative 387-square-foot floor. The maker does not print that 4.8-ACH number directly. It reaches the site’s medium tier, but not the 606-square-foot large-room tier. A connected app cannot compensate for an undersized room plan, open doorways or a purifier hidden behind furniture.

The product page lists CADR figures of 249 smoke, 261 dust and 230 pollen without a unit beside those numbers. I leave the generic CFM value unknown, so a hard CFM minimum cannot be satisfied from those figures alone. Coway’s product page also says particles down to 0.01 microns, while the manual describes the Max2 filter as capturing up to 99.97% of particles down to 0.3 microns. Those are different manufacturer claims; there is no independent measurement here. Use the stated room-area basis and your own practical airflow needs rather than interpreting a small-particle phrase as a complete health guarantee.

What Wi-Fi adds—and what remains local

The 250S can connect to Coway’s IoCare+ app for monitoring and remote control; Coway also lists an app scheduler, voice control and timer choices of one, two, four or eight hours through the app. The precise voice-assistant compatibility is not specified on the model page, so do not assume a particular ecosystem. The manual’s pairing instructions point users to Coway’s app guide. Initial setup therefore depends on an internet-connected home network and a working phone-app account.

The buttons on the appliance remain useful without selecting a remote task: you can turn it on, choose Smart, Rapid or Sleep behavior, set three manual fan speeds, turn indicator lights on or off, adjust pollution-sensor sensitivity and reset the filter indicators. Smart mode uses the local particle sensor; the bar on the appliance shows broad color categories rather than a numeric PM2.5 reading. A phone may provide a different view, but this is not a numeric display on the purifier itself. If app access is an essential requirement, this model differs from the regular 250 and the Airmega 250 Art, which have no Wi-Fi operation documented in their manuals.

Filter care is a real part of the connected choice

The washable pre-filter catches larger hair and dust before the Max2 set, which combines activated carbon and Green True HEPA media. Coway’s manual suggests cleaning the pre-filter about every two weeks using its daily-eight-hours-at-maximum-speed basis. It gives the Max2 cartridge an approximate twelve-month replacement life under that same basis, while the live product page lists a six-to-twelve-month range. If your room is dusty, the indicator may prompt earlier maintenance; reset it after cleaning or replacing the relevant filter. Do not wash or reuse the Max2 cartridge.

Opening the unit means removing the front cover and lifting the pre-filter. Unplug it first; a washed pre-filter needs to dry fully in the shade before it goes back. Clean the particle sensor and the air outlet regularly because dust buildup can affect sensing or airflow. The replacement filter page explicitly lists compatibility across the Airmega 250, 250S and 250 Art. The purifier does not document an automatic pre-filter scraper, a dedicated pet cycle, an aroma pad or a separate TVOC sensor.

Footprint, sound and the version to compare against

The manual identifies the Wi-Fi model as AP-1720G. The exact U.S. offer record is product 7071501320351, variant 41061430919327, SKU 826439000394 and barcode 00000113924. The page and manual agree on 18.5 inches wide, 19.7 inches high, 20.5 pounds and 64 watts. The listed depth is 8.3 inches on the page and 8.03 in the manual, so do not rely on a tight depth limit without checking the physical installation. Coway publishes a 22–54 dB(A) range; performance and sound vary with fan setting.

Pick the 250S if remote scheduling and app monitoring change how you will use it. If the same local Auto behavior is enough, compare the simpler Airmega 250 before paying for connectivity. If visual design matters most, the 250 Art has a decorative front but its room figure is slightly lower and its power/noise records conflict. Above this family’s medium-room basis, step to a Coway model with a larger documented repeated-air-change rating.

Primary references: Coway’s Airmega 250S product page, the linked Airmega 250/250S U.S. manual, and the shared replacement-filter page.