Coway air purifiers that run constantly at high speed are usually reacting to a dirty or contaminated air quality sensor, not a failed motor or control board. This issue is common across Coway models and is often repairable without replacing major parts.
Most Coway air purifier problems come down to airflow restriction, sensor errors, or fan-related wear rather than complete failure. Units that appear “broken” are often reacting to clogged filters, dirty sensors, or environmental conditions rather than defective parts.
Coway air purifier repairs typically cost between $80 and $350 depending on the failed component. Minor issues like sensors or fans are inexpensive, while control board failures can approach replacement cost.
Coway air purifiers typically last 7–10 years with regular use, and their filters generally last 6–12 months depending on model and air quality. In my experience as a technician servicing dozens of units, some run reliably for over a decade with proper maintenance, while heavy indoor pollutants can shorten filter life.