Coway Airmega 400S Review: Whatever you need in this Smart enabled air purifier!

Airmega 400S review

The starters

Simplicity meets modern architecture. Coway Airmega 400S manage to perfect the art of design VS practicality with its seamless dual side air inlet. Sharing the same dimension as 400, the 14.8 x 22.8 x 14.8 in size and 24.7 lb weight is considerably compact for its category if you discounted the four fixed legs. Build quality is top-notch that does not seem to be any signs of ozone off-gassing or air by-pass. Upfront the air cleaner comes with standard LED ring air quality indicator that shows real-time (every minute) indoor air pollution. Up to four different colors will be shown to indicate the current air quality status ranging from Good (Blue and green), Moderate (Green and yellow), Unhealthy (Yellow and pink) to Very Unhealthy (Pink and red). Finally, to lift or transport the air purifier around, simply hold on to both sides of the handles.

Airmega 400S controls are located at the top black panel that separates into two sections. On the left side, you will find a Wi-Fi button, Light button, Pre Wash button and Max2 change button plus a round light sensor. Touching the Wi-Fi button connect the air purifier to a Wi-Fi network. The Wi-Fi LED indicator will start blinking when the pairing is in progress and stays constant once a stable connection is established. The light button will either turn on or off the air quality indicator light. Pre Wash button will shows the pre-filter cleaning cycle at 5 levels: 100%, 80%, 60%, 49%, 20%, and 0%. Once the button is lit, you will need to clean the pre-filter. To reset the Pre Wash filter Lifetime notifications, touch and hold the button for 2-3 seconds until the button light is off. The above steps apply to Max2 Change button, but instead of cleaning the filter, you will need to replace the Max2 filter. Light sensor function by detecting the intensity of its surrounding light. When the air purifier is in Smart mode and everything is in pitch black for 3 minutes, Sleep mode will be activated automatically. Moving to the right side, you have a big main Power button that is self-explanatory. Touch the button once to turn on the air purifier, touch and hold the same button again for 2-3 seconds will turn it off. To manage the fan speed or purifying mode, either touch the air speed or Sleep mode on the curve bar, or swipe your finger upward or downward to select the desired speed/ mode. One more secret function that most people didn’t know unless they read the manual (how many of you does that), you can adjust the pollution sensor’s sensitivity by holding on the Light button +Smart bar. Continue by selecting one of the air speed ( speed 1 = sensitive, speed 2 = normal, speed 3 = less sensitive). Overall, all buttons are responsive, clearly labeled with dedicated indicator light, and an unseen, intuitive swiping speed control.

Like 300S, the Wi-Fi enabled feature that allows you to control the air purifier at any place via Coway IoCare app. Pairing is easy for both Apple and most Android phones so long you have strong Wi-Fi connectivity. We did encounter some issues with some lower end model (Huawei to be exact but that is few off case scenario) that requires multiple retries. Once successfully connected the air purifier to Wi-Fi network, you can access to features such as Smart Monitoring, Real-time Air Monitoring, Indoor Air Quality Report (including records from past week), Outdoor Air Quality Monitoring (check air quality in your city), Scheduler/ Timer, Speed and Smart Mode Control (Auto/ Sleep mode). Other than popular timer/ speed control, the highlights would definitely be the scheduler that allows you to program a weekly schedule when to turn on or off the machine. Airmega 400S also works with Amazon Alexa where you could manage the air purifier via the given list of command. The standard list of voice command includes turning on or off, switching to Smart or Sleep mode, changing the fan speed, set timer, filter life status and check air quality.

Briefly go through other key specification again: A standard 4-stage filtration, 3 fan speed with Smart mode (Auto/ Sleep/ Eco), Pre-filter/ MAX2 life-time indicator (actual filter real-time usage lifespan), Wi-Fi enabled for Airmega’s IoCare app and Amazon Alexa support (more on this later), timer/ scheduler (via app), air quality indicator, 30 days money back guarantee and 5 years warranty.

Airflow, speed, and CADR

Coway Airmega 400S is the top end in the series so naturally it has best in-class purifying coverage. With 2 air charges every 30 minutes, expect a wide 1560 sq. ft. purifying coverage. Coverage drop to half at around 780 sq. ft. coverage with 4 air charges every 15 minutes. For normal non-allergic situation, the 2 charges purifying coverage and airflow delivery rate is more than sufficient for most room size including living hall. Smart mode is the default mode that allows autonomous purifying according to room air quality. Switching to Sleep mode will reduce noise and power usage for night use, or manually select one of the 3 speed. CADR is also equally impressive as the purifying coverage. Overall dust, pollen, and smoke have an outstanding 350 cfm figures (Optimal speed). Significantly higher than most air purifiers CADR output within its segment. Based on the figures itself, the air purifier would have no problem handling heap of dust, indoor habitant microorganisms plus smoke and odor pollutants.

What’s inside count

^ Airmega 400S filters/ technologies/ lifespan

Airmega 400S uses the same 4-stage filtration setup that is proven against the test of time. Essentially a dual pre-filter plus Max2 filter bundled (Green True HEPA filter and Activated Carbon filter), each pre-filter would be placed at both sides of air inlet to clear out any large incoming airborne contaminants before reaching to the Max2 filters. With large particles out of the way, Green True HEPA filter and Activated Carbon filter in Max2 would have the full capacity (99.7% for HEPA and 99% for carbon) in capturing tiny microorganisms, gases and odors. There is no optional Ionizer included in the filtration list; Not a big miss for some.

Keep it down

22 - 52 dB noise level is the same as 400 model. Reasonable but not overly silent at low speed and slightly lower to normal conversion noise level at max speed. Usable in bedroom if you crank it in Sleep mode. The 6 - 66 watts power consumption is in an identical pattern with low consumption rate at sleep/ low speed and high consumption rate at medium/ high speed. To further enhance the eco-friendliness, there is ECO mode where the air cleaner would shut down the fan when the room air quality is good for at least 10 minutes. Auto mode would also prevent any energy wastage where the air purifier would only run at a higher speed if the surrounding air quality is poor.

At what cost

Coway Airmega 400S air purifier is the highest in the brand hierarchy hence it is the costliest. We do think it's worth every penny you paid however, if you have no use of the supportive features, large room space purifying or the strong airflow delivery rate, maybe it's time to consider the smaller alternatives like Airmega 300S or other equivalent models. Annual filter replacement cost is more reasonably priced with plenty of availability, but do take note it is in a bundled Max2 set which consists of both HEPA and Activated Carbon filter.

Airmega 400S VS the challengers

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