AHU Air Handling Unit Filter Gel

INTRODUCTION
Central air handling units in commercial buildings, hospitals, and industrial plants move thousands of cubic meters of air per hour through multiple filter stages from pre-filters to bag filters to HEPA terminals. Between each filter section and the unit casing, bypass gaps allow unfiltered air to mix with clean air, reducing effective filtration efficiency by 5 to 15 percent in poorly sealed installations. Traditional compression gaskets on filter frames lose resilience under continuous fan vibration and thermal expansion-contraction cycles from seasonal heating and cooling, creating visible light gaps at frame joints. Addition-cure platinum silicone jelly gel fills these bypass gaps as a liquid that cures into a flexible, adhesive seal conforming to any irregularity in the filter track or casing weld. The gel self-healing property means that when maintenance staff slide out a filter element for replacement, the gel seals again automatically when the new filter is pushed in. This eliminates the recurring cost and labor of replacing gaskets on every filter change cycle, which in large AHU installations with 50 or more filter frames can represent significant annual maintenance expenditure and occupational health exposure during manual gasket replacement work.


PRODUCT REQUIREMENTS
In air handling unit filter channel service the gel must: maintain seal integrity across approximately minus 5 to 50 degrees Celsius, including humid cooling-coil sections where condensation is routine; resist mold growth and remain odorless under sustained 80 to 95 percent relative humidity; adhere to galvanized steel, aluminum and powder-coated channels without primer; absorb fan vibration and airflow pressure pulsation without cracking or channeling; accept repeated filter withdrawal and reinsertion during seasonal maintenance; show no oil bleed or water absorption that could reduce tack; allow visual fill checks through its blue color; comply with RoHS and REACH; and retain stable penetration and tack after long-term humid-heat aging so energy loss from bypass air stays below design targets. The gel should remain odorless during first commissioning heating and should not require prolonged ventilation before floors are occupied. It should accept minor top-up filling years after installation without visible layering, and its cured surface should tolerate light mechanical contact during filter handling without gouging. Long-term performance should be supported by documented aging data so energy auditors can verify that bypass leakage remains negligible over the AHU service life. The material should remain stable when channels are located immediately downstream of outdoor-air dampers, where sudden temperature changes occur, and it should not dry out at the exposed upper surface after years of airflow. Minor vibration marks from frame edges should disappear without manual intervention.

CORRESPONDING PRODUCT MODEL PARAMETERS
Recommended model: HY-9400 - Blue high-tack grade for AHU filter gel channels and HVAC bypass seals requiring strong vibration-resistant adhesion and repeated filter change recovery.

GRADE SELECTION GUIDE
HY-9400 is blue, with a penetration of 200 (0.1 mm) and high tack. It is the typical choice for HEPA/ULPA filter gel channels, biosafety cabinet seals, and applications requiring strong adhesion and re-sealability.
HY-9405 is blue, with a penetration of 170 (0.1 mm) and medium tack. It suits electronic potting, sensor encapsulation, and applications balancing softness and dimensional stability.
HY-9409 is transparent, with a penetration of 150 (0.1 mm) and low tack. It is used for transparent gel pads, intimate apparel, prosthetic devices, and applications requiring visual clarity or easy repositioning.

FREQUENTLY ASKED QUESTIONS
Q: Can the gel seal bypass gaps on the negative-pressure side of an AHU without being sucked into the airstream? A: Yes. The gel is applied as a thixotropic liquid that stays in place without running, then cures into a tacky gel body. Even under negative pressure of 500-1000 Pa, the cured gel adheres firmly to the track and does not extrude or shed particles into the airstream. Field installations in hospitals and clean manufacturing plants confirm zero gel migration after 12 months of continuous operation.
Q: How do maintenance staff replace a filter in a gel-sealed AHU section? A: Pull the filter frame straight out of the track. The gel self-heals the channel left by the frame. Slide the new filter in. The gel wraps around the new frame edge and re-seals within minutes. No separate gasket, no sealant reapplication. Staff training takes less than 30 minutes, and the blue color makes it easy to spot any unfilled gaps during post-maintenance inspection.
Q: What is the return on investment for switching from gaskets to gel in a large AHU installation? A: For a 60-filter AHU bank, gel material cost per fill is 30-50 kg. Compared to 60 compression gaskets replaced every quarter, gel eliminates recurring gasket purchases, reduces filter-change labor by 20-30 minutes per bank, and cuts bypass leakage from 10 percent to below 1 percent. Payback is typically within 12-18 months through combined energy savings and maintenance cost reduction.

QUALITY ASSURANCE & CERTIFICATION
Every batch of Hong Ye HY-94 series jelly gel is produced under ISO 9001 certified quality management in a dedicated silicone workshop, with incoming raw-material inspection, in-process mixing control and finished-product testing on every batch. Before release each lot is checked for viscosity, mix ratio, cure time, penetration, color and tack, and a Certificate of Analysis (COA) listing the actual measured values ships with every order. Standard grades carry RoHS 2.0 and REACH SVHC test reports; skin-contact and baby-care grades can be supplied with FDA 21 CFR 177.2600 and LFGB Section 30/31 reports and, on request, ISO 10993 biocompatibility testing; flame-retardant grades meet UL94 V-0. Food-contact, medical and export orders are supported by the corresponding compliance files for customer qualification. Hong Ye has manufactured and supplied jelly gel to contractors, filter builders and equipment makers in over 60 countries since 2005, with monthly capacity above 500 tons, batch traceability and multi-language documentation. Application engineers provide grade selection, sample evaluation, on-site or video pouring guidance and after-sales follow-up, and technical data sheets (TDS), safety data sheets (SDS) and test reports are available before order to support tender and audit processes.


CONCLUSION
The market for tank sealant jelly gel in this application area continues to expand as cleanroom construction, electronic encapsulation, automotive electrification, energy storage and consumer product manufacturing drive demand for reliable two-component addition-cure silicones. Hong Ye supports this growth with ISO 9001 certified production, 500-plus ton monthly capacity, complete compliance documentation and responsive application engineering. Buyers evaluating suppliers are advised to look beyond unit price and compare batch-to-batch consistency, documentation completeness, delivery stability and technical service responsiveness, because the cost of a sealing or potting failure - rework, downtime, certification delay or product recall - far exceeds the incremental cost of a quality gel. Choosing the correct grade for the channel, operating temperature and service environment, following the 1:1 mixing and pouring procedure and validating with a small trial batch all help secure a durable seal. Hong Ye welcomes sample requests and application enquiries; our engineers will recommend the HY-9400, HY-9405 or HY-9409 grade that matches the sealing or potting requirement and support qualification from first sample through volume production.

CONTACT US
SHENZHEN HONG YE JIE TECHNOLOGY CO., LTD — Silicone Rubber Manufacturer, 23 Years
Contact: Kimi (Sales)
Mobile / WhatsApp / WeChat: 0086-18938867594
Email: hyjd@szrl.net
Website: www.szrl.net
Address: Building A, No.3, Hongling First Road, Liulian Shibi, Pingdi Street, Longgang District, Shenzhen, China