What is a purge cycle in an air handling unit, and when is it typically used?

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Multiple Choice

What is a purge cycle in an air handling unit, and when is it typically used?

A purge cycle is a short, intentional flush of outdoor air through the air handling unit to replace stale indoor air and clear contaminants from the ducts and space. It’s not a continuous process; it happens briefly to refresh the air rather than run all the time. It’s typically used at system start-up, after occupancy changes that may introduce odors or contaminants, or during periods when only ventilation is desired (no cooling or heating load) so fresh air is introduced before normal operation resumes. This helps maintain good indoor air quality and prevent buildup in the ducts. Purge cycles aren’t tied to humidity alone, and they’re still a valid part of many ventilation strategies.

A purge cycle is a short, intentional flush of outdoor air through the air handling unit to replace stale indoor air and clear contaminants from the ducts and space. It’s not a continuous process; it happens briefly to refresh the air rather than run all the time. It’s typically used at system start-up, after occupancy changes that may introduce odors or contaminants, or during periods when only ventilation is desired (no cooling or heating load) so fresh air is introduced before normal operation resumes. This helps maintain good indoor air quality and prevent buildup in the ducts. Purge cycles aren’t tied to humidity alone, and they’re still a valid part of many ventilation strategies.

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