What kind of HEPA filter should be equipped with high-efficiency air supply vents?

The high-efficiency air supply vent seems to have a simple structure - a box plus a filter element. However, when selecting the actual model, the box and the filter element are two sets of interfaces. If either side is not aligned, air will leak or the pressure will not be tight when installed.

There is only one core judgment criterion: the grade, air volume, resistance and sealing method of the filter element must be consistent with the box design. Top air inlet, side air inlet and liquid tank type boxes have different interface conditions, and one solution cannot be used to cover all air supply outlets.

Let’s first look at the shape of the box

The high-efficiency air supply outlet is divided into top air inlet and side air inlet according to the air inlet method, and is divided into gasket compression and liquid tank seal according to the sealing method. The interface conditions of these combinations are quite different.

For top-intake boxes, the airflow enters from above, and there is usually a flow-equalizing space between the filter element installation surface and the air inlet. For side air inlet boxes, the air inlet direction is biased to one side. If there is no internal flow guide structure, the wind speed distribution on the air inlet surface of the filter element is likely to be uneven. Please pay attention to this when selecting.

The liquid tank sealed box has more specific requirements for the filter element: the position of the knife edge, the width and depth of the tank body, and the insertion depth must all correspond to the size of the liquid tank of the filter element. For verification methods of this type of interface, please refer to Instructions for liquid tank sealing HEPA .

The air volume is calculated based on the actual burden of this end

The high-efficiency air supply outlet is a terminal device, and the air volume it bears is allocated by the system, not the total air volume of the unit.

When selecting a filter element, you should use the design air volume of this air supply outlet to check the resistance of the filter element at that air volume. If the air volume distribution of several air supply outlets in the same system is inherently uneven, it is easy to cause problems when selecting the filter element based on the average value - if the air volume is assigned to the one with a larger air volume, the actual operating point will exceed the applicable range of the filter element.

In addition, if you change the filtration level or replace a filter element with a different thickness, you should also check the available static pressure of the air conditioning system. If the resistance of the filter element changes, the terminal air volume may change accordingly. This is common in renovation projects.

Sealing methods and leak detection should be considered together

After the filter element is installed in the box, whether the surrounding frame can be inspected determines the feasibility of subsequent maintenance.

For the box pressed by the gasket, confirm whether the pressing parts are evenly distributed and whether the four corners can be pressed in place. For a box with a liquid tank seal, make sure that the edges of the knife are continuous all around after being inserted into the tank and that the corners are not disconnected.

It is better to think clearly about leak detection accessibility during the selection stage than to find that the probe cannot be inserted after installation. If the diffuser plate or diversion structure blocks the frame, it will have to be disassembled and assembled during acceptance, which will affect every subsequent maintenance.

When replacing, check the entire set of interfaces

When replacing the filter element after running for a period of time, do not just measure the length and width.

The same external dimensions, different sealing methods, and different positions of the pressing surfaces will result in completely different installation effects. If a gasket-type box is replaced with a tank-type filter element, or vice versa, it may lack a correct pressing surface. Therefore, before replacement, it is best to check the box drawings and filter element drawings together to confirm that the sealing structure, installation depth and maintenance direction are correct.

About Aili Industrial's high-efficiency air supply vent matching

Ai Li industrial production HEPA/ULPA air filter and high-efficiency air supply outlet, box and filter element can be matched in the same system. The sealing method, knife edge size and maintenance interface are confirmed together at the planning stage to reduce on-site rework caused by mismatched interfaces.

For projects where the filter element needs to be replaced in an existing box, box drawings or on-site measured dimensions can be provided to facilitate verification of the sealing structure and installation depth of the filter element. involving For FFU fan filter units or other end-type systems, it is also recommended to confirm the end interface and unit parameters together to avoid changing the system air volume distribution just by changing the filter element.