In a terminal reheat system, what is the main purpose?

In a terminal reheat system, the primary purpose is to maintain desired temperature conditions by reheating air at terminal units. This system is often implemented in heating, ventilation, and air conditioning (HVAC) applications where precise control over a space's temperature is critical.

When air is delivered to terminal units, it may initially not reach the desired temperature set for a specific zone or space. The terminal reheat function allows for the adjustment of air temperature just before it enters the occupied space, ensuring that occupants experience comfortable conditions. This function is especially important in systems that utilize variable air volume (VAV), where airflow is adjusted to meet the cooling or heating demands but may require supplementary heating to achieve the setpoint temperature effectively.

The other options do not capture the primary focus of a terminal reheat system. While cooling air or controlling humidity can be aspects of overall HVAC function, the essence of a terminal reheat system is to adjust the temperature of the air delivered to the space for comfort, making option B the most accurate representation of its main purpose.