Most air handling unit manufacturers assemble their units with a panel and an aluminum alloy or angle steel welded frame. Ensuring proper sealing of the enclosure is a crucial aspect to consider during selection, as excessive leakage can lead to two consequences: insufficient airflow and leakage within the negative pressure air handling chamber. In summer, this allows untreated hot and humid air to enter the air supply system, causing the dew point to fail to meet design requirements and compromising supply air temperature parameters.
The manufacturing standard for modular air conditioning units (GB/T14294-08) issued by the State Bureau of Technical Supervision stipulates that "when the static pressure inside the unit is maintained at 700Pa, the air leakage rate shall not exceed 3%." Some manufacturers incorporate dovetail-shaped sealing grooves into the air handling unit frame, along with corresponding rubber sealing strips, ensuring an air leakage rate of less than 2% under rated operating conditions, meeting the standard requirements. This is a good solution to the air leakage problem.
