How to replace multiple ULPA units in batches? Status differences and construction arrangements

Multiple unitsULPA filters should be replaced in batches and should be arranged according to operating status, regional dependency and maintenance window to avoid processing only in numerical order. The difference in resistance between the old and new filter elements may also change the air volume distribution of the system. Replacing in batches may seem like a scheduling issue, but it is actually a system balance issue: when a batch is replaced, the system resistance distribution changes once, and the air volume distribution of adjacent modules also changes. Supported by Aili IndustryThe FFU computer group control system can record the operating parameters of each module before and after replacement, making it easier to observe changes in air volume distribution during the batch process, instead of only discovering that the air volume in a certain area is low after all replacements are completed.

1. Divide batches according to status, not in numerical order

Determine priorities based on differential pressure, leak detection, damage, process area requirements and spare parts availability. The age of use can be used as a background, but cannot alone determine the order.

The operating status of filter elements put into operation in the same batch may be very different: the resistance close to the dust source rises quickly, and seals that are frequently disassembled and assembled may have problems first. Aili Industry isWhen HEPA/ULPA filters are delivered, we can cooperate with the project party to establish corresponding records of points and numbers, and determine which ones should be replaced first based on the pressure difference and leak detection data of each point.The partition operation data of the FFU computer group control system can be used as one of the basis for batching, rather than just looking at the operation date. The relationship between levels and filtering requirements can be found inISO cleanliness level comparison。

2. Analyze the impact of batch operation: partial shutdown may affect regional pressure

Check adjacent modules, common air ducts and group control methods to evaluate whether partial shutdown affects regional pressure or pollution control.

Multiple ULPA units often share air ducts or the same group control zone. If a part is stopped for core replacement, the air volume and pressure difference of the remaining modules will change. Aili Industry isthe FFU fan filter unit supports individual adjustment of operating status by area. When replacing in batches, the operation settings of adjacent areas can be retained to reduce the impact on the entire partition. The group control solution of Multiple devicesFor scenarios where the fan filter unit on the EFU equipment side is shared, please refer tothe EFU FAQ and technical support .Instructions on shared air ducts are provided in

3. The difference in resistance between the old and new filter elements will change the air volume distribution

The new filter element has low initial resistance, while the old filter element has high resistance. When mixed in the same air duct, more air volume will flow to the side of the new filter element. The practice of intensively replacing one side and retaining the old parts on the other side can easily cause air volume deviation.

Aili Industry isWhen non-standard ULPA filters are supplied in batches, the batch specifications can be unified according to project requirements to reduce the resistance difference between different batches; the group control system can record the air volume of each module, making it easy to adjust the operating status according to the data after batching. Please refer to the method for rebalancing the air volume.HEPA FAQs and Selection Guide。

4. Each batch completes an independent closed loop, and finally reviews the overall system

Record replacement points, operating settings and test results, and rebalance if necessary. Ultimately the system as a whole should be reviewed rather than simply adding up the batches of reports.

Each batch of replacement units should have independent installation leak detection, air volume recording and rectification closed loop. After all replacements are completed, a system-level review should be conducted. Aili Industry isWhen ULPA ultra-high-efficiency filters are delivered, we can cooperate with the project party to establish a batch replacement ledger, and record the points, models, test results and operating parameters of each batch accordingly, so as to facilitate traceability during the final overall review. For the relationship between batch and overall review, please refer toULPA ultra-high efficiency filter FAQ and selection guide。

5. Related questions and answers

Can all in the same batch be switched to a higher level?
The fan, resistance and acceptance requirements need to be separately evaluated, and the upgrade cannot be treated as an ordinary replacement. Grade changes will alter the system resistance distribution, requiring rechecking of operating points.

Is it possible to arrange replacement in batches only according to the date of operation?
Not recommended. The operating status of filter elements put into operation in the same batch may vary greatly, and should be comprehensively sorted based on pressure difference, leak detection and process area requirements.

The air volume is low after the old and new filters are mixed. What should I do?
The air volume distribution of each module should be checked and rebalanced if necessary. The operating data recorded by the group control system can help determine the direction of deviation.

6. Related articles

ULPA ultra-high efficiency filter FAQ and selection guide

FFU computer group control system

FFU equipped with ULPA ultra-high efficiency filter

HEPA FAQs and Selection Guide

7. Key points for selection and acceptance inspection

8. Product matching and technical support from Aili Industrial

Aili Industry isThe group control solution of the FFU fan filter unit supports individually adjusting the operating status by area, and the supportingThe FFU computer group control system can record the operating parameters of each module before and after replacement, making it easier to observe changes in air volume distribution during the batch process.The delivery of HEPA/ULPA filters can be coordinated with the establishment of point number records and batch replacement ledgers.Non-standard ULPA filters are supplied in batches and batch specifications can be unified according to project requirements.ULPA ultra-high efficiency filter can be used with the final overall review, and can be combined in scenarios where multiple devices are shared.The fan filter unit on the EFU equipment side confirms the air duct relationship. Provide process objectives, installation drawings, operating conditions and acceptance requirements, and can further communicate ULPA standard specifications, non-standard interfaces, samples and batch matching. The specific parameters and test range are based on the confirmed model and technical documents.