What is the primary mechanism by which refrigerant-based dehumidifiers reduce humidity?

Refrigerant-based dehumidifiers operate primarily by cooling the air below its dew point. This cooling process causes the moisture in the air to condense on the cold surfaces of the dehumidifier, such as the evaporator coils. When air is cooled to a temperature where it can no longer hold all the moisture it contains, the excess moisture condenses into liquid water, which is collected and drained away. This mechanism is effective in reducing the humidity levels in the environment, making it crucial for managing moisture in various settings, particularly in water damage restoration and commercial drying.

In contrast, the other choices do not accurately describe the primary function of refrigerant-based dehumidifiers. Heating the air would actually increase humidity levels, while adding moisture would counteract the purpose of dehumidification. Filtering the air may improve air quality but does not inherently reduce humidity levels. Consequently, cooling the air below the dew point is the fundamental principle driving the effectiveness of refrigerant dehumidifiers in managing humidity.