Description
Product Overview
The HMA401224 is a 12x24x4 washable aluminum aluminum mist eliminator filter filter engineered for permanent installation in HVAC systems, outside air ducts, side-access housings, and built-up filter banks where airborne water droplets, oil mist, or coolant mist must be separated from the airstream before reaching downstream equipment. As an impingement-type panel filter, the HMA401224 serves two essential functions: its primary role is to collect large water droplets and oil mist and divert the captured liquid to an appropriate drain; its secondary function is as a heavy-duty washable particulate air filter rated for continuous operation at temperatures up to 275°F. Independently tested and verified, this aluminum aluminum mist eliminator filter filter achieves 99%+ efficiency on water droplets measuring 3 microns and larger, providing reliable moisture protection for chilled water coils, mist-type humidifiers, and outdoor air intake systems.
Constructed with a precision-formed .030” thick aluminum frame, 24 gauge aluminum face grids on both the air entry and exit sides, and a 15-ply aluminum screen wire moisture separator wire media pack—multiple layers of corrugated and flat screen wire positioned for efficient drainage, placed between two layers of expanded metal—the HMA401224 delivers consistent moisture separation and particulate filtration performance with the structural durability required for demanding commercial and industrial HVAC applications. With actual dimensions of 11.375” H x 23.375” W x 3-3/4″ D (±1/8”), this filter installs precisely in standard 12x24x4 nominal filter housings in outside air ducts, side-access filter housings, and built-up filter banks throughout commercial and industrial HVAC systems.
Unlike electrostatic or pleated media filters designed primarily for fine particulate capture, the HM Series aluminum mist eliminator filter operates on the impingement principle: water droplets and oil mist in the airstream cannot follow the tortuous path through the corrugated aluminum screen wire moisture separator wire layers at rated velocity, causing them to collide with the screen wire surfaces where surface tension holds the collected liquid. The captured liquid accumulates and drains by gravity through the 3/8” diameter drain holes along the bottom of the filter frame when installed in the correct upright orientation with the TOP label facing upward. This passive drainage mechanism requires no power, pumps, or active components—gravity moves collected moisture to the drain while the HVAC system operates normally. The 15-ply aluminum screen wire media pack provides the optimal combination of tortuous path length, surface area, and drainage channel geometry for efficient liquid separation at rated 500 fpm airflow.
The HMA401224 is manufactured by American Metal Filter Company (AMFCO) with precision construction ensuring reliable long-term performance and dimensional accuracy for proper housing fitment. The all-aluminum construction—frame, face grids, and screen wire media—provides consistent corrosion resistance in moisture-laden applications where the filter is continuously exposed to water droplets and elevated humidity conditions. The frame’s pop-rivet corner construction and mitered joints maintain the critical 11.375” x 23.375” face dimensions within ±1/8” tolerance throughout the filter’s operational lifetime. For HVAC engineers, building operators, and facilities managers who need reliable moisture separation and heavy-duty washable particulate filtration in a single permanent filter unit, the HMA401224 delivers the performance, durability, and economics of the HM Series in a standard 12x24x4 nominal size.
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Key Benefits of the HMA401224 Aluminum aluminum mist eliminator filter Filter
- 99%+ Efficient on 3-Micron Water Droplets: Independently tested and verified to capture over 99% of water droplets measuring 3 microns and larger, providing reliable moisture protection for chilled water coils, downstream HVAC components, fan motors, and ductwork systems where uncaptured moisture causes corrosion, biological growth, and equipment damage
- Dual Function — Moisture Separation and Particulate Filtration: Primary function as an impingement-type aluminum aluminum mist eliminator filter is complemented by secondary heavy-duty washable particulate filtration capability, making the HMA401224 a versatile single-filter solution for applications requiring both moisture control and airborne particle capture in one permanent filter unit
- Permanent washable mist eliminator filter design: Rinse with warm water to restore full aluminum mist elimination and moisture separation and filtration performance—no replacement media required. Eliminates the recurring cost and logistics of disposable filter programs while maintaining consistent moisture separation performance throughout decades of residential, commercial, and industrial HVAC service
- 275°F Maximum Operating Temperature: Rated for continuous operation at temperatures up to 275°F—substantially higher than electrostatic filter alternatives—making the HMA401224 suitable for demanding commercial and light industrial applications with elevated air temperatures where lower-rated filters would be damaged or degraded
- Heavy-Duty 15-ply Aluminum Screen Wire Construction: Multiple layers of corrugated and flat aluminum screen wire provide the tortuous path geometry required for efficient impingement-type moisture separation, with sufficient structural integrity for frequent washing and long-term service in harsh environments including outdoor air intakes, industrial ventilation, and coolant mist applications
- Gravity Drainage System: 3/8” diameter drain holes along the bottom of the aluminum frame collect and divert captured moisture to a drain when the filter is installed upright with the TOP label facing upward. This passive drainage system requires no power, pumps, or active components—gravity handles captured liquid disposal during normal HVAC operation
- All-Aluminum Construction: .030” thick aluminum frame, 24 gauge aluminum face grids, and aluminum screen wire media provide consistent corrosion resistance in moisture-laden HVAC environments. Unlike galvanized or coated steel alternatives that can rust or corrode when continuously exposed to water droplets and elevated humidity, aluminum maintains structural integrity and dimensional accuracy throughout decades of moisture-separation service
- Made in USA by AMFCO — UL Classified 900: Manufactured by American Metal Filter Company with precision quality control ensuring consistent dimensional accuracy, proper fitment in standard HVAC housings, and reliable moisture separation performance throughout years of demanding commercial and industrial service. Optional polyurethane gaskets available for side-access housing applications
Technical Specifications
The HMA401224 12x24x4 aluminum mist eliminator filter delivers verified performance specifications for moisture separation and particulate filtration in commercial and industrial HVAC applications. All specifications conform to the authoritative AMFCO HM Series Tech Sheet and independent test report. The comprehensive data below covers every dimension, material, and performance parameter required for HVAC system design, procurement specifications, facility maintenance documentation, and regulatory compliance records.
| Specifications: | Details: |
|---|---|
| Model Number | HMA401224 (HM Series — Aluminum Mist Eliminator Filter) |
| Nominal Size | 12” x 24” x 4” |
| Actual Dimensions | 11.375” H x 23.375” W x 3-3/4″ D (±1/8” H&W, ±1/16” depth) |
| Frame Material | .030” thick aluminum |
| Frame Construction | Precision-mitered corners secured with pop rivets; 3/8” diameter drain holes along bottom of frame |
| Face Grid Material | 24 gauge aluminum (both air entry and exit sides) |
| Media | Aluminum screen wire — 15-ply: multiple layers of corrugated and flat screen wire positioned for efficient drainage |
| Media Pack Placement | Pack placed between two layers of expanded metal |
| Filter Type | impingement-type moisture separator filter washable panel filter |
| Primary Function | Moisture/mist separation — collects water droplets and oil mist; diverts liquid to drain |
| Secondary Function | Heavy-duty washable particulate filtration |
| Water Droplet Efficiency | 99%+ efficient on water droplet size of 3 microns and larger (independently tested) |
| Water Droplet Efficiency Detail | 2.5–3 micron: 94.9% • 3–4 micron: 99.1% • 4–5 micron: 99.9% |
| Dust Arrestance / Capacity | Not officially rated for this depth — primary function is moisture/mist separation at 500 fpm |
| Rated Airflow | 500 fpm face velocity |
| Recommended Airflow Range | 450–550 fpm |
| Maximum Operating Temperature | 275°F continuous |
| Recommended Final Resistance | 0.50 inches W.G. before cleaning |
| Cleaning Method | Rinse with moderate-to-heavy stream of warm water; air dry before reinstalling |
| Adhesive Coating Option | Not supplied from factory; may optionally be sprayed with Filter Coat (water-soluble adhesive and detergent) before installation |
| Gasket Option | Available with polyurethane gaskets on vertical sides for side-access housing applications (specify at order) |
| Installation Orientation | TOP label must face upward for moisture separation drainage |
| Drain Hole Placement | 3/8” diameter drain holes along bottom of frame |
| Washability | Frequent and moderate |
| Filter Weight | 5.85 lbs |
| Compliance & Certifications | UL Classified 900 |
| UPC Code | 840373524785 |
| GTIN Code | 00840373524785 |
| Country of Origin | Made in USA |
Commercial & Industrial Applications
The HMA401224 12x24x4 aluminum mist eliminator filter delivers reliable performance across commercial, institutional, and light industrial environments where airborne moisture, water droplets, oil mist, or coolant mist must be separated from the airstream to protect downstream HVAC equipment, prevent corrosion and biological growth, and maintain system performance. The impingement-type aluminum screen wire construction, 275°F temperature rating, and all-aluminum corrosion resistance make this filter suitable for continuous operation in demanding applications that would degrade or destroy lower-rated filter alternatives.
Outside Air Intakes and Ventilation Systems
Commercial and institutional buildings’ outside air intake systems subject HVAC equipment to rain entrainment, wind-driven water, morning dew, and seasonal precipitation that introduce liquid water into ductwork and air handling equipment. The HMA401224 installed at outside air intake locations captures water droplets before they reach fan sections, coils, controls, and downstream filter banks, preventing moisture accumulation that causes rust, corrosion, biological growth, and equipment failure. Commercial office buildings, hospitals, schools, and institutional facilities with outside air systems in coastal, humid, or precipitation-prone climates benefit from the HMA401224’s 99%+ capture efficiency on 3-micron and larger water droplets, combined with the passive gravity drainage system that continuously removes captured moisture during normal HVAC operation without operator intervention. Building engineers specifying outdoor air system protection rely on the HM Series mist eliminator’s long service history and verifiable test data to meet ventilation system performance requirements and equipment warranty conditions.
Chilled Water Coil Protection
Chilled water coil sections in commercial air handling units generate condensate during normal cooling operation, and coil surfaces can become sites for airborne moisture accumulation that migrates downstream when airflow velocity exceeds the coil’s carry-over limit. Installing the HMA401224 downstream of chilled water coil sections captures carried-over moisture droplets before they reach supply ductwork, fan sections, and terminal equipment, protecting investments in downstream components and preventing moisture-related indoor air quality problems. Data centers, server rooms, precision manufacturing facilities, healthcare environments, and other applications with strict humidity control requirements benefit from the HMA401224’s combination of high-efficiency moisture capture and heavy-duty washable particulate filtration in a single permanent panel filter unit that installs in standard 12x24x4 nominal side-access or built-up filter bank positions.
Mist-Type Humidifier Applications
Steam and evaporative humidifier systems introduce moisture into airstreams to maintain required relative humidity levels in commercial buildings, data centers, healthcare facilities, museums, and manufacturing environments where humidity control is critical for occupant comfort, process control, or material preservation. Improperly positioned or oversized humidifiers can introduce unevaporated water droplets into ductwork that cause corrosion, biological growth, and moisture damage to insulation and finishes downstream. Installing the HMA401224 downstream of mist-type humidifier discharge points captures unevaporated droplets before they enter distribution ductwork, providing a reliable safeguard against water damage from humidifier over-injection events while also providing heavy-duty particulate filtration of the humidified supply air stream.
Industrial and Coolant Mist Applications
Light industrial manufacturing operations using coolant mist delivery systems, metalworking equipment, or process cooling generate oil mist and coolant aerosols that must be captured before entering building HVAC systems or exhausting to outside air. The HMA401224’s impingement-type aluminum screen wire construction captures oil mist and coolant aerosol droplets through the same mechanism it uses for water droplets, collecting the captured liquid in the frame and draining it by gravity when installed upright. Industrial ventilation engineers specifying mist control for machining centers, stamping operations, and cooling tower exhaust applications select the HM Series aluminum mist eliminator for its 275°F temperature rating, all-aluminum construction compatible with coolant chemistry, and heavy-duty washable mist eliminator filter design that withstands the frequent and rigorous cleaning demanded by industrial operating environments. The HMA401224 handles the demanding conditions of industrial mist control applications that would rapidly degrade electrostatic, pleated, or cardboard-framed filter alternatives.
Construction Features
The HMA401224 12x24x4 aluminum mist eliminator filter represents precision construction engineered for decades of reliable moisture separation and particulate filtration performance across thousands of wash cycles and years of demanding commercial and industrial HVAC service. Every component is specified to deliver consistent impingement-type mist capture, structural durability, corrosion resistance, and complete washability—from the precision-mitered aluminum frame with drain holes to the 15-ply aluminum screen wire media pack and dual 24 gauge aluminum face grids.
Aluminum Frame with Gravity Drainage
The precision-formed .030” thick aluminum perimeter frame provides exceptional structural rigidity for a 12x24x4 panel filter while resisting corrosion from continuous moisture exposure in mist elimination applications. The all-aluminum construction eliminates the rusting and frame deterioration that affect galvanized or coated steel frames when continuously exposed to water droplets, coolant mist, and elevated humidity conditions at temperatures up to 275°F. Precision-mitered corner joints secured with pop rivets create true 90-degree angles that maintain the critical 11.375” x 23.375” face dimensions within ±1/8” tolerance across years of service, ensuring proper housing fitment that prevents bypass around the filter perimeter in side-access housings and built-up filter banks. The 3/8” diameter drain holes positioned along the bottom of the frame are the essential feature distinguishing the HM Series from standard particulate filters: they provide the exit path for captured moisture that has accumulated in the filter and collected at the bottom under gravity. When installed with the TOP label facing upward, captured water droplets and oil mist flow downward through the screen wire media, collect at the frame bottom, and exit through the drain holes to an appropriate drain location, maintaining continuous moisture removal during normal HVAC operation without operator intervention.
15-Ply Aluminum Screen Wire Media Pack
The 15-ply aluminum screen wire media pack is the performance core of the HMA401224, providing the tortuous impingement path geometry required for efficient water droplet and oil mist capture at rated 500 fpm airflow. Multiple layers of corrugated and flat screen wire alternated in a precise pattern create an extended series of direction changes that airborne water droplets cannot navigate at rated velocity—they collide with wire surfaces where surface tension holds the captured liquid until it accumulates enough to drain by gravity to the frame bottom and out through the drain holes. The corrugated wire layers create the direction-change geometry while the flat layers provide drainage channels that guide captured liquid efficiently to the frame drain holes without re-entrainment into the airstream. This construction achieves the verified 94.9% efficiency at 2.5–3 microns and 99.1% efficiency at 3–4 microns documented in the independent test report, with 99.9% capture at 4–5 microns and above. The aluminum wire composition resists corrosion from water, common coolants, and moderate concentrations of cleaning agents, maintaining structural integrity and drainage channel geometry through frequent washing operations over decades of service. The entire media pack is placed between two layers of expanded metal that protect it from physical damage during installation, removal, and washing while maintaining uniform face velocity distribution across the entire filter area.
24 Gauge Aluminum Face Grids
24 gauge aluminum face grids on both the air entry and exit sides of the HMA401224 provide uniform airflow distribution across the entire filter face area while protecting the aluminum screen wire media pack from physical damage during installation, removal, and the moderate washing operations for which the HM Series is rated. The entry-side grid prevents contact damage to the screen wire layers during installation in tight side-access housing configurations, while the exit-side grid supports the media pack against airflow pressure at the elevated 500 fpm rated velocity. The expanded metal grid pattern promotes consistent face velocity that ensures even distribution of moisture droplets across the full filter area, maximizing impingement contact with the screen wire media and capture efficiency throughout the entire face. Aluminum construction matches the frame and media materials for consistent corrosion resistance, ensuring the face grids maintain structural integrity and airflow characteristics through years of washing cycles and moisture-laden operating conditions in commercial and industrial HVAC environments.
Maintenance & Cleaning
The HMA401224 12x24x4 aluminum mist eliminator filter requires periodic washing to maintain optimal moisture separation performance and restore the 15-ply aluminum screen wire media pack’s capture efficiency. The washing process is straightforward—requiring only access to warm running water—and the AMFCO tech sheet specifies “frequent and moderate” washability for the HMA aluminum model. Regular washing removes accumulated particulate from the screen wire layers, restores the tortuous path geometry for efficient impingement capture, and clears any drainage channels that may have become partially obstructed. High-powered steam cleaning and chemical dips are unnecessary and not recommended per AMFCO manufacturer specifications.
Washing Procedure
Remove the HMA401224 filter from your HVAC system by sliding it out of the filter housing or releasing any side-access housing retention hardware. Note the TOP label orientation so the filter can be reinstalled correctly for moisture drainage. Take the filter to a utility sink, hose bib, or outdoor washing area with access to warm running water at moderate pressure. Hold the filter with the dirty face down and rinse from the clean side through to the dirty side, allowing water to carry accumulated dust and debris out through the loaded face. Continue rinsing until water runs completely clear. For filters used in oil mist or coolant mist applications with adhesive residue accumulation, a mild detergent solution can be used followed by a thorough fresh-water rinse. Do NOT use high-pressure washing equipment that could deform the corrugated screen wire layers or dislodge the media pack from between the expanded metal face guards. Allow the washed filter to air dry completely or shake off excess water before reinstalling in moisture separation applications—though some residual moisture is acceptable since the filter is designed to operate in a liquid-laden environment. If Filter Coat adhesive treatment is used, apply it after washing and drying before reinstallation per Filter Coat product instructions.
Washing Frequency Guidelines
The HMA is rated for “frequent and moderate” washing, making it suitable for maintenance programs that require regular cleaning without concern for media degradation from repeated washing cycles. Washing frequency depends on your specific application, particulate loading, and moisture exposure rates. Outside air intake applications in dusty or high-particulate environments may require washing every 1–3 months. Chilled water coil protection and humidifier applications in commercial buildings typically require washing every 3–6 months under normal conditions. Industrial and coolant mist applications with higher loading rates may require monthly or more frequent washing depending on observed accumulation patterns and system differential pressure trends. For all applications, visual inspection is the most reliable washing indicator—when the screen wire layers appear visibly loaded with dust or the drain holes show signs of partial blockage, washing is warranted regardless of elapsed time. Systems with building automation differential pressure monitoring can use filter pressure drop rise above initial clean-filter readings as an objective washing trigger.
Optional Filter Coat Treatment
Unlike EC Series electrostatic filters (where adhesive coatings are explicitly not recommended), the HM Series aluminum mist eliminator filter may optionally be treated with Filter Coat, a water-soluble adhesive and detergent, before installation. Filter Coat can improve particulate capture in the secondary filtration function by making screen wire surfaces tacky for fine dust adhesion. To apply, spray the filter face lightly with Filter Coat before installation per the product instructions. Filter Coat is water-soluble and washes off during routine filter cleaning, so reapplication after each wash cycle is required if adhesive-enhanced particulate capture is desired for your application. Contact Metal Air Filters to inquire about Filter Coat availability for use with your HMA401224 installation.
Installation
Installing the HMA401224 12x24x4 aluminum mist eliminator filter follows procedures compatible with standard HVAC aluminum mist eliminator filter housings accepting 12x24x4 nominal size filters, but requires one critical orientation step not required with standard particulate filters: the filter must be installed with the TOP label facing upward in all moisture separation applications to ensure captured liquid drains correctly through the bottom frame drain holes.
Pre-Installation Checklist
Before installing the HMA401224, verify that your filter housing accepts 12x24x4 nominal size filters with actual interior dimensions accommodating the 11.375” H x 23.375” W x 3-3/4″ D filter, with ±1/8” tolerance on height and width. Confirm your HVAC system operating temperature does not exceed 275°F at the filter location. Identify the TOP label on the filter frame and confirm the housing orientation allows the TOP label to face upward during installation—this is mandatory for correct moisture drainage. Locate the drain holes along the bottom of the filter frame and confirm they align with or can drain to an appropriate liquid collection point. If your application uses side-access filter housings and you ordered the gasket option, verify the polyurethane gaskets are properly positioned on the vertical frame sides before installation. If Filter Coat adhesive treatment is desired, have it available to apply to the filter face before installation. Clean the filter housing interior of accumulated dust and debris from previous filter service.
Installation Steps
Shut down your HVAC system completely before accessing the filter compartment. Remove any existing filter from the housing, noting the position of any drain connections or collection points at the housing bottom. Clean the filter housing interior using a vacuum or damp cloth. Orient the HMA401224 with the TOP label facing upward—this is critical for moisture drainage. Insert the filter into the housing maintaining the upright TOP-label-up orientation throughout the installation process. Press the filter firmly into place ensuring all four edges of the aluminum frame seat properly against the housing walls. In side-access housings, ensure the polyurethane gaskets (if ordered) compress properly against the housing interior walls to create a moisture-tight seal that prevents liquid bypass around the filter frame. Secure the filter using the housing’s retention mechanism per your specific system design. Verify that the drain holes at the bottom of the installed filter are unobstructed and positioned to drain captured moisture to an appropriate collection point—a housing drain pan, floor drain, or connected drain line. Close and secure the filter access door or panel. Restore power and restart the HVAC system. Record the installation date and orientation in your maintenance log. During the first operating period after installation, check the drain area for moisture drainage to confirm the filter is correctly positioned and draining as expected.
Complementary Products
Metal Air Filters offers a complete range of washable and permanent filter solutions for HVAC applications with different performance requirements, temperature ratings, and filtration strategies. The HMA401224 provides moisture separation and heavy-duty washable particulate filtration; the following products address adjacent application requirements.
Washable Electrostatic Air Filters — EC Series
For applications requiring fine particulate filtration with passive electrostatic technology and MERV 6 performance rated up to 150°F:
• 12x24x1 Washable Electrostatic Air Filter (ECA101224) — MERV 6 passive electrostatic filter for standard residential and commercial HVAC particulate control applications
• 20x20x1 Washable Electrostatic Air Filter (ECA102020) — Popular commercial 20x20x1 electrostatic filter for building HVAC systems requiring MERV 6 particulate capture without moisture separation
Media Pad Holding Frames — HPG Series
For applications where replaceable filter media pads are preferred over permanent washable filters:
• 12x24x1 Media Pad Holding Frame (HPG101224) — Galvanized steel holding frame for filter media pad replacement strategy in standard commercial HVAC applications
• 20x20x1 Media Pad Holding Frame (HPG102020) — Commercial standard galvanized steel holding frame for applications preferring periodic media replacement over filter washing maintenance
Frequently Asked Questions
How does the HMA401224 mist eliminator filter work?
The HMA401224 operates on the impingement principle: water droplets and oil mist cannot follow the tortuous path through the 15-ply corrugated aluminum screen wire layers at rated 500 fpm velocity and collide with wire surfaces. Surface tension holds the captured liquid on the wire until it accumulates and drains by gravity through the 3/8” drain holes along the bottom of the frame to an appropriate drain point. This passive impingement mechanism achieves 99%+ efficiency on 3-micron and larger water droplets without electricity, moving parts, or active components.
How do I clean and wash the HMA401224?
Remove the filter and rinse with a moderate-to-heavy stream of warm water from the clean side through to the dirty side until water runs completely clear. High-powered steam cleaning and chemical dips are unnecessary and not recommended. Shake off excess water and air dry or reinstall (some residual moisture is acceptable in moisture separation applications). If Filter Coat adhesive treatment is used, reapply after each wash cycle. Do NOT use high-pressure equipment that could deform the corrugated screen wire layers.
Why must the HMA401224 be installed with the TOP label facing upward?
The 3/8” drain holes are positioned along the bottom of the filter frame specifically to allow captured moisture to drain by gravity when the filter is installed upright with the TOP label facing up. If installed sideways or upside down, captured liquid cannot reach the drain holes and will accumulate in the filter, reducing moisture separation and water droplet separator efficiency, potentially causing liquid re-entrainment into the airstream, and creating conditions for biological growth in the housing. Always install with the TOP label facing upward in all moisture separation applications.
What is the maximum operating temperature of the HMA401224?
The HMA401224 HMA aluminum model is rated for continuous operation at 275°F. This is substantially higher than EC Series electrostatic filters (150°F) and covers most commercial and light industrial HVAC applications. For applications requiring higher temperatures, AMFCO offers the HMG galvanized steel model (325°F) and HMS stainless steel model (900°F) in the same HM Series configurations.
What are the actual dimensions of the HMA401224?
The HMA401224 has actual dimensions of 11.375” H x 23.375” W x 3-3/4″ D (±1/8” on H and W, ±1/16” on depth). The nominal size is 12x24x4. Note that HM Series filters use a 5/8” undercut on height and width—not the 1/2” undercut used by some other filter series. This means actual height = nominal H minus 5/8” and actual width = nominal W minus 5/8”.
Can I use Filter Coat adhesive on this aluminum mist eliminator filter filter?
Yes—unlike EC Series electrostatic filters (where adhesive coatings are not recommended), the HM Series aluminum mist eliminator may optionally be sprayed with Filter Coat, a water-soluble adhesive and detergent, before installation. Filter Coat can improve fine particulate capture in the secondary filtration function. It washes off during routine cleaning, so reapplication after each wash is required if adhesive treatment is desired.
Are gaskets available for this filter for side-access housing applications?
Yes—the HM Series may be supplied with polyurethane gaskets on the vertical sides of the frame for use inside side-access housings where a moisture-tight seal between the filter frame and housing walls is required. Specify “with gaskets” and indicate which dimensions (short or long side) require gaskets when placing your order. Contact Metal Air Filters to add the gasket option to your HMA401224 order.
How does the HMA aluminum model compare to the HMG and HMS models?
All three models use the same aluminum screen wire media and HM Series impingement design. The HMA uses .030” thick aluminum frame and 24 gauge aluminum face grids for applications up to 275°F with “frequent and moderate” washability. The HMG galvanized steel model handles up to 325°F with “frequent and rigorous” washability for demanding industrial environments. The HMS stainless steel model handles up to 900°F for extreme temperature industrial applications. Contact Metal Air Filters if your application requires the HMG or HMS model instead of the HMA.
How often should I wash the HMA401224?
The HMA is rated for “frequent and moderate” washing. Frequency depends on your application: outside air intakes in dusty environments typically require washing every 1–3 months; commercial building moisture separation applications typically every 3–6 months; industrial coolant mist applications may require monthly washing. Visual inspection of the screen wire face and monitoring for reduced drainage through the drain holes are the most reliable indicators for washing timing.
Does this filter work with all commercial HVAC systems?
The HMA401224 fits standard 12x24x4 nominal filter positions in outside air ducts, side-access housings, and built-up filter banks. It is designed for rated 500 fpm face velocity (recommended range 450–550 fpm), which is higher than standard residential HVAC airflow—this filter is designed for commercial and industrial applications with higher air velocities where impingement-type moisture separation is effective. Verify your system operates within the 450–550 fpm range at the filter face for optimal moisture separation performance.
Why Choose the HMA401224 12x24x4 Aluminum Mist Eliminator?
The HMA401224 HM Series aluminum mist eliminator filter solves a critical problem in commercial and industrial HVAC systems: moisture entrainment in airstreams that damages equipment, promotes corrosion and biological growth, and compromises downstream filtration and system performance. With independently verified 99%+ water droplet capture efficiency on 3-micron and larger droplets, the HMA401224 provides reliable permanent protection for chilled water coils, fan sections, ductwork, and building equipment against moisture damage at operating temperatures up to 275°F—without power, replacement media, or complex installation requirements. The passive gravity drainage system through the 3/8” bottom drain holes removes captured moisture continuously during normal HVAC operation, requiring only periodic washing to maintain peak performance.
Built with precision-formed .030” thick aluminum framing, 15-ply corrugated and flat aluminum screen wire media, and 24 gauge aluminum face grids on both sides, the HMA401224 combines structural durability with all-aluminum corrosion resistance essential for long-term moisture separation service. The 12x24x4 dimensions install in standard outside air duct, side-access housing, and built-up filter bank positions throughout commercial and industrial HVAC infrastructure. The straightforward warm-water washing procedure restores full moisture separation and particulate filtration performance without specialized tools or cleaning agents. Optional polyurethane gaskets for side-access housings and optional Filter Coat adhesive treatment provide installation flexibility for demanding applications. Made in USA by American Metal Filter Company to exacting dimensional and construction standards, the HMA401224 delivers the consistent quality and performance that commercial HVAC engineers, building operators, and industrial facilities managers demand from critical moisture control infrastructure.
Choosing the HMA401224 permanent washable aluminum mist eliminator eliminates recurring disposable filter replacement costs while providing a higher level of moisture protection than standard particulate filters designed for dry particulate capture. The combination of 99%+ water droplet efficiency, heavy-duty secondary particulate filtration, 275°F temperature capability, and decades-long all-aluminum durability makes this filter the engineering-sound choice for any commercial or industrial HVAC application where moisture entrainment, chilled water coil carry-over, humidifier droplet carryover, or coolant mist demands a proven, permanent impingement-type separation solution in a standard 12x24x4 nominal panel filter footprint.
