Hydrophilic Coated Aluminum Fin Stock 0.1-0.3mm Thickness with 500 Hours Salt Spray Resistance for HVAC Heat Exchanger Coils

This hydrophilic coated 3003 aluminum sheet is fin stock engineered for the wet side of an air-conditioning coil. The substrate is AA3003 aluminium-manganese alloy rolled down to 0.10–0.30 mm in H22, H24 or H26 temper — hard enough to survive a high-speed fin press yet ductile enough to form tall collars without tearing.

Both faces then receive a thin hydrophilic film, typically one to two grams per square metre, which pulls the surface contact angle below ten degrees. On an untreated fin, condensing water beads up into droplets that bridge the gap between adjacent fins; the gap closes, air flow collapses and the coil loses capacity while static pressure climbs. With the hydrophilic layer, condensate spreads into a continuous film that drains to the bottom of the coil and leaves the air path open, so dehumidification stays stable and the fan draws less power.

The coating also carries corrosion inhibitors that survive 500 hours of salt spray, which protects the fin pack in coastal installations and in rooftop units exposed to acid rain. Fin stock is supplied in eye-to-sky coils with interleaved VCI paper so the surface arrives clean and immediately press-ready.

• Condensate Control: Contact angle below 10 degrees turns droplets into a draining film, preventing water bridging between fins and keeping air flow open.
• Stable Coil Capacity: Maintaining the fin gap preserves heat transfer and static pressure during long dehumidification cycles instead of losing capacity as water builds.
• Corrosion Inhibitors: Hydrophilic film with built-in inhibitors passes 500 hours of salt spray, protecting coastal and rooftop coil packs.
• Press-Ready Temper: H22 to H26 tempers form tall fin collars at high press speed without cracking or losing collar height.
• Uniform Coating Weight: Roll coating holds film weight between 1.0 and 2.0 g/m² so drainage behaviour is consistent from the first metre to the last.
• Clean Coil Surface: VCI interleaving and eye-to-sky winding keep the surface free of oxide dust and handling marks before pressing.

Residential split systems, ducted units and VRF outdoor units consume most of this fin stock, followed by commercial air handlers, chillers and fan-coil units. Heat pump evaporators rely on the hydrophilic layer during long heating and defrost cycles, when melt water has to leave the coil quickly to avoid refreezing.

Refrigeration applications include display cases, cold rooms and transport refrigeration condensers, where the corrosion resistance also helps in wash-down environments. Dehumidifiers and dryer coils use the same material because continuous condensate drainage is the whole point of their operation. Outside HVAC, the coated foil appears in automotive radiators, charge air coolers and battery cooling plates, and in ventilation energy-recovery cores where aluminium fins alternate with membrane layers.

Coils are wound eye-to-sky, interleaved with VCI paper, wrapped in PE film and strapped to wooden pallets; a 20GP container carries up to 20 metric tons. Coating weight, contact angle, adhesion and salt spray are tested on every coating batch, and a coating performance report is issued with the mill certificate.

Because fin presses are sensitive to thickness variation, gauge is monitored continuously during rolling and the profile is logged for each coil.