
Coway Airmega 400S
Score: 92/100
Air Health Haven Plus
Score: 78/100Rankings

The Coway Airmega 400S is a powerful, Wi-Fi-enabled smart air purifier for large spaces up to 3,120 square feet, featuring True HEPA filtration and app control. Its main trade-off is the high cost of annual filter replacements and its bulky size. It is ideal for users managing large open spaces who require powerful purification and remote monitoring capabilities.

The Air Health Haven Plus is an in-duct HVAC air purifier that uses UV-C light and PCO technology to neutralize pathogens and reduce VOCs throughout the whole house. While it offers significant energy savings and zero-ozone safety, it requires annual lamp replacements and lacks smart features. It is best suited for homeowners with central HVAC systems who want whole-house germ reduction without portable units.
| Attribute | ![]() | ![]() |
|---|---|---|
1,560 sq_ftbest | — | |
400 cfmbest | — | |
| ↓ lower better | 22 dBbest | — |
12 monthsbest | 12 monthsbest | |
| ↓ lower better | 66 watts | 30 wattsbest |
5best | — | |
| ↓ lower better | 24.7 lbs | 7 lbsbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Performance(3) | ||
Coverage Area (sq_ft) | 1560 sq_ft | Whole House sq_ft |
Clean Air Delivery Rate (CADR) (cfm) | 400 cfm | null cfm |
Noise Level (dB) | 22 dB | null dB |
Filtration(1) | ||
Filtration Type | True HEPA | UV-C/PCO/Carbon |
Smart Features(2) | ||
Air Quality Sensor | true | false |
Smart Connectivity / App Control | true | false |
General(1) | ||
Warranty | 5 years | 10 years |
Power & Energy(2) | ||
Power Consumption (watts) | 66 watts | 30 watts |
Energy Efficiency Rating | Energy Star | High |
Design(1) | ||
Weight (lbs) | 24.7 lbs | 7.0 lbs |
Controls(5) | ||
Fan Speeds | 5 | null |
Control Interface | Touch/App | Manual |
Timer Settings | true | false |
Sleep Mode | true | false |
Remote Control | true | false |

Products in the top-left offer the best value (high score, low price).

Professional reviewers consistently rank it as a class leader in air cleaning performance, awarding it top marks for CADR ratings and large-space coverage up to 3,120 square feet.
Consumers express strong satisfaction with rapid dust removal and smart integration, but complain about the financial impact of yearly filter replacements and occasional wireless pairing difficulties.

“Fresher air instantly... odors gone”

“Easy install, blue glow confirms it's working... family breathes easier”

“AC runs better, lower bills”




Professional reviewers and HVAC experts consistently highlight the Haven Plus as a top-tier in-duct purification solution, particularly praising its multi-stage approach that combines UVC germicidal light with PRO-Cell PCO technology for comprehensive VOC and odor reduction.
Everyday users express high satisfaction with the immediate improvement in indoor air freshness and the straightforward DIY installation process that requires no specialized tools or professional assistance. Common praise centers on the visible blue glow confirming operation, reduced household odors, and lower energy bills from cleaner AC coils.