G4 Z-Line cassette filters for AHU filter banks and ventilation units

Cassette filters are the standard filters for filter banks in medium and large air handling units (AHU) — ventilation plants for offices, hotels, hospitals, shopping centres and any HVAC installation where filters are mounted in slide-in frames or fixed rails and replaced in batches.

Z-Line construction: synthetic fibre filter media pleated in a Z-fold (accordion-style), mounted in a moisture-resistant rigid cardboard frame. The Z configuration increases the active filtration area compared to a simple panel filter at the same overall dimensions — lower initial hydraulic resistance and greater dust-holding capacity, meaning longer replacement intervals.

G4 class: captures coarse particles (dust, fluff, insects, textile fibres) — the mandatory primary filter before any fine filtration or HEPA stage. Without an effective G4 filter, downstream fine and HEPA filters clog rapidly and replacement costs escalate.

Available sizes: wide range of standard dimensions for the most common AHU frames (450×600×50 mm, 595×595×50 mm, 490×592×48 mm and others). Measure exactly before ordering — a 5 mm difference makes the filter leak around its frame.

Replacement frequency: every 3–6 months under normal conditions; more frequently in high-traffic or dusty spaces (professional kitchens, adjacent industrial areas). Replace at first visibly increased differential hydraulic resistance or per the AHU preventive maintenance schedule.

👉 Compact filters for small AHUs 👉 Modular units with multiple filtration stages