AC Infinity Air Filter Box with High Efficacy Filter | 4-Inch

Quick Spec: 4" duct opening | 23.46 x 8.42 x 11.73 in. | 80–400 CFM | Accepts 12 x 20 x 1 pleated filter | 1mm SPCC steel body | Matte black powder-coated finish | SKU: AC-AFB4

Precision Control in Any Space

Every unfiltered duct intake is a liability running on borrowed time. Dust loads accumulate on fan blades and reduce static pressure output. Mold spores and fine particulates enter the air column and settle on surfaces where they compound contamination risk with every cycle. Operators who rely on open intakes or improvised pre-filter wraps are not managing their air — they are reacting to it, spending labor hours on remediation that a properly engineered intake would have prevented entirely. The cost is not always visible in a single cycle, but it accumulates in degraded air quality, increased cleaning frequency, and the unpredictable contamination events that interrupt production at the worst possible moments.

After the Air Filter Box 4" is installed at the starting end of the duct circuit, the intake air column is defined and controlled. Particulates are intercepted before they reach the fan, the duct run, or the environment being served. Filter changes are scheduled maintenance events, not emergency responses. The slide-lock door means access to the filter chamber takes seconds, not tools. The air moving through the system is the air the operator intended — not whatever happened to be suspended in the ambient environment at the time of intake.

The mechanism behind that outcome is a 1mm cold-rolled SPCC steel enclosure with aluminum duct flanges, a hinge-sealed door with a soft neoprene layer that creates a dust-free seal at the chamber boundary, and a 12 x 20 x 1 pleated filter slot that accepts standard MERV-rated filters — with the included filter rated at 90% efficiency for particles in the 0.3–1.0 micron range. The 3.81-inch duct opening and 3.21-inch flange are dimensioned for direct connection to CLOUDLINE S4 and T4 fans, and the system operates across an airflow range of 80–120 CFM minimum to 400 CFM maximum with little to no airflow restriction. In practical terms, the Air Filter Box 4" delivers 90% particle capture efficiency across the 0.3–1.0 micron range at up to 400 CFM through a 23.46 x 8.42 x 11.73 in. steel enclosure rated for extreme weather exposure.

Where This Belongs (and Doesn't)

Installation and duct connection work must comply with applicable local mechanical and building codes. Disconnect all power to connected fan equipment before installing or servicing this unit. This product is a passive filtration enclosure — it does not replace active pressure management or carbon filtration for odor control beyond the included filter's rated capture range.

How It Works

The Air Filter Box 4" functions as a sealed filtration chamber inserted at the duct intake. Ambient air enters through the 3.81-inch duct opening, passes through the 12 x 20 x 1 pleated filter seated in the 1-inch deep filter slot, and exits through the 3.21-inch aluminum flange into the connected duct run. The filter intercepts particles in the 0.3–1.0 micron range at 90% efficiency — a capture range that covers dust, lint, mold spores, pollen, dust mites, and fine particulates including welding fumes. The included filter meets MERV 8 classification (MPR 600, FPR 5), capturing lint, household dust, pollen, dust mites, and mold. Operators requiring broader capture can upgrade to MERV 11 (MPR 1000–1200, FPR 7) for added pet dander, smoke, smog, and cough/sneeze particle capture, or MERV 13 (MPR 1500–1900, FPR 10) for virus and bacteria interception in addition to all lower-tier particles — all standard MERV-rated 12 x 20 x 1 filters are compatible with this enclosure.

The enclosure body is 1mm thick cold-rolled SPCC steel with a matte black powder-coated finish rated for extreme weather exposure. Aluminum duct collars at both connection points resist corrosion at the flange interface. The hinge-sealed door uses a slide lock mechanism and a soft neoprene interior layer to create an airtight seal at the chamber boundary — preventing bypass contamination where unfiltered air could otherwise enter around the filter frame. Filter access requires releasing the slide lock and opening the hinged door; no tools, no duct disconnection, no interruption to the connected fan circuit. The system operates across a minimum airflow range of 80–120 CFM and a maximum of 400 CFM, sized for direct pairing with CLOUDLINE S4 and T4 fans operating within their rated static pressure output. In practical terms, the Air Filter Box 4" processes up to 400 CFM through a 1mm SPCC steel enclosure measuring 23.46 x 8.42 x 11.73 inches, with a neoprene-sealed hinge door providing tool-free filter access and full MERV 8 through MERV 13 filter compatibility.

Commercial Assurance

System Integration

• Primary Fan Pairing: Engineered for direct connection to AC Infinity CLOUDLINE S4 and CLOUDLINE T4 inline fans — high static pressure output from these models ensures the filter media operates within its rated efficiency range without starving the duct circuit of airflow.
• Duct Circuit Position: Install at the starting end of the duct run, upstream of the inline fan, to intercept particulates before they reach fan blades, motor housings, or downstream environments.
• Filter Upgrade Path: The 12 x 20 x 1 filter slot accepts any standard MERV-rated pleated filter — operators can step from the included MERV 8 baseline to MERV 11 or MERV 13 as facility contamination profiles require, without changing the enclosure.
• Atmospheric Control Ecosystem: The AC-AFB4 functions as the intake filtration node in a broader atmospheric control circuit — pair with CLOUDLINE fan speed controllers, carbon filters at the exhaust end, and environmental monitors to build a closed-loop air management system with defined inputs and measurable outputs.
• Maintenance Scheduling: The slide-lock hinge door enables filter inspection and replacement on a defined schedule without tools or duct disassembly — supporting a preventive maintenance protocol rather than reactive intervention.

Facility Integration Data

The table below models per-unit and fleet-level cost of ownership for the AC-AFB4 across 10, 20, and 50-unit deployments, using the $119.00 MAP price and a conservative MERV 11 filter replacement cost of approximately $8–12 per filter at quarterly replacement intervals.

Operator Field Notes

• Install at intake, not exhaust: The AC-AFB4 is rated for intake-side positioning at the starting end of the duct run. Installing on the exhaust side reverses the pressure differential across the filter media and degrades capture efficiency.
• Disconnect fan power before filter service: The slide-lock door provides fast access, but the connected CLOUDLINE fan must be powered down before opening the chamber — airflow through an open chamber during filter removal will redistribute captured particulates.
• Remove all plastic packaging from the filter before installation: The included pleated filter ships with protective wrapping. Operating the unit with packaging material on the filter will immediately restrict airflow and may damage the fan motor.
• Match fan static pressure to filter MERV rating: Upgrading to MERV 13 increases filter resistance. Confirm that the connected CLOUDLINE S4 or T4 fan can maintain target CFM against the higher static pressure load before deploying MERV 13 media in this enclosure.
• Inspect the neoprene door seal at each filter change: The airtight seal at the chamber boundary depends on the neoprene layer maintaining contact with the door frame. Check for compression set or debris accumulation on the seal surface during every scheduled maintenance interval.
• Establish a filter replacement schedule before deployment: The 90% capture efficiency rating is a function of clean filter media. A loaded filter that has not been replaced on schedule will restrict airflow and reduce capture efficiency simultaneously — schedule replacements based on facility particulate load, not calendar defaults.

Operator FAQ

Shipping & Logistics

• Shipping Jurisdiction: Cannafull Spectrum Solutions ships within the contiguous 48 United States only. Orders to Alaska, Hawaii, U.S. territories, or international addresses cannot be processed through this channel.
• Carrier & Transit: The AC-AFB4 ships via standard ground carrier. Estimated transit times vary by destination. Tracking information is provided at time of shipment. Inspect packaging for damage before signing for delivery — note any visible damage on the carrier receipt before the driver departs.
• Returns: Returns are accepted in accordance with the Cannafull Spectrum Solutions return policy. Units must be in original, uninstalled condition with all original packaging and components present. Defective units are handled separately under manufacturer warranty procedures — contact support at cannafullspec.com to initiate either process.
• Restocking Fee: Returns of non-defective items are subject to a restocking fee of up to 25% per our Return Policy. Review full terms at cannafullspec.com/pages/return-policy before ordering.

Technical pre-sale questions and post-sale support: cannafullspec.com

What's in the Box

• 1x Air Filter Box 4" enclosure (AC-AFB4) — fully assembled, matte black powder-coated 1mm SPCC steel body with aluminum duct flanges
• 1x Pleated air filter (12 x 20 x 1) — MERV 8 baseline, pre-installed or separately packaged depending on shipment configuration

Contents confirmed from manufacturer source data. No additional hardware, mounting brackets, duct tape, or fan components are included. Verify contents against this list immediately upon receipt and contact cannafullspec.com within 48 hours if any item is missing or damaged.

Regional Compliance & Deployment Notes

• U.S. Deployment Only: The AC-AFB4 is sold and supported through Cannafull Spectrum Solutions for deployment in licensed facilities across the contiguous United States. No Canadian distribution, Health Canada compliance documentation, or CSA certification is available or represented through this channel.
• Mechanical Code Compliance: Duct filtration installations are subject to local mechanical codes in many jurisdictions. Operators are responsible for confirming that the installation configuration — including duct sizing, filter box positioning, and fan pairing — meets applicable local and state mechanical requirements before commissioning.
• Electrical Safety: The AC-AFB4 is a passive filtration enclosure with no electrical components. However, it is installed in-line with powered fan equipment. All electrical connections to CLOUDLINE or other fan models must comply with applicable NEC requirements and local electrical codes. Disconnect power before any installation or maintenance activity on the filter box or connected fan.
• Facility Licensing: Operators in licensed cultivation, processing, or manufacturing facilities should confirm that air filtration specifications meet any particulate control requirements specified in their facility license, state agency guidance, or third-party audit standards before selecting a MERV rating tier.
• UPC: 819137021693 (AC-AFB4). Confirm SKU and UPC match at receipt for inventory and compliance recordkeeping.

Product specifications, pricing, and availability are subject to change without notice. All data presented on this page is sourced from AC Infinity manufacturer documentation current at time of publication. Cannafull Spectrum Solutions makes no representations beyond what is stated in verified manufacturer source data. Confirm current specifications, warranty terms, and compliance documentation directly with AC Infinity or through cannafullspec.com before making procurement decisions for licensed facility deployments.