What is the function of an adiabatic humidifier?

• A. It evaporates water into the air, reducing its temperature.
• B. It filters dust particles from the air.
• C. It heats air to the desired temperature.
• D. It cools air without changing moisture.

Answer: (D)

An adiabatic humidifier adds moisture to the air by evaporating water into the airstream. The energy needed to turn liquid water into vapor comes from the air itself, so latent heat is drawn from the air and the dry-bulb temperature drops as humidity increases. The device’s purpose is to increase moisture in the space, not to filter dust or to heat the air; and unlike a cooling-only device that lowers temperature without changing humidity, an adiabatic humidifier cools the air while raising its humidity.