Bare foil
Rolled and annealed with no surface treatment. Mature, low-cost and with good base heat transfer. Limitations: condensate forms droplets that bridge the fins and the bare surface corrodes faster in humid or salty air.
HVAC foil guide
8011 Aluminium Foil for Air Conditioners
8011 is the most widely used alloy for air-conditioner fin foil: an aluminium-iron-silicon alloy that forms well, conducts heat efficiently and costs less than manganese- or magnesium-bearing alternatives. It is supplied 0.08 – 0.2 mm thick, bare or with hydrophilic, hydrophobic or corrosion-resistant coatings. This guide explains each type, the specifications, and how to choose the right 8011 foil for the climate and the coil design.
- Alloy
- 8011 / EN AW-8011A
- Tempers
- O, H22, H24, H26
- Thickness
- 0.08 – 0.2 mm
- Width
- Up to about 1800 mm
Why 8011 is the standard AC fin alloy
An air-conditioner coil is a bundle of copper or aluminium tubes threaded through thousands of thin aluminium fins. The fins provide most of the heat-transfer area on the air side, so their material, thickness and surface treatment strongly affect cooling capacity, noise, energy use and service life.
8011 contains about 0.5 – 0.9 % silicon and 0.6 – 1.0 % iron. These elements form fine intermetallic particles that give the foil more strength and a finer grain than pure 1100 or 1200 aluminium, while keeping excellent ductility for drawing fin collars. It is produced in very large volumes for foil and closures, which keeps it economical and widely available.
For most residential and light commercial units, 8011 in an H22 or H24 temper with a hydrophilic coating is the default choice. Where the design needs thinner or stiffer fins, 8006 fin stock is the usual upgrade.
8011 composition (wt %)
Registered Aluminum Association limits for 8011. European specifications usually call up EN AW-8011A, with slightly different silicon and iron ranges; the certificate shows which applies.
| Element | Minimum | Maximum |
|---|---|---|
| Silicon (Si) | 0.50 | 0.9 |
| Iron (Fe) | 0.6 | 1.0 |
| Copper (Cu) | — | 0.10 |
| Manganese (Mn) | — | 0.20 |
| Magnesium (Mg) | — | 0.05 |
| Chromium (Cr) | — | 0.05 |
| Zinc (Zn) | — | 0.10 |
| Titanium (Ti) | — | 0.08 |
| Others, each / total | — | 0.05 / 0.15 |
| Aluminium (Al) | Remainder |
Standards for 8011 air-conditioner foil
| Standard | Scope |
|---|---|
| EN 546-1 to -4 | Aluminium foil: delivery conditions, mechanical properties, dimensional tolerances and surface requirements |
| EN 683-1 to -3 | Fin stock specifically: delivery, mechanical properties and dimensions |
| EN 573-3 | Chemical composition (EN AW-8011A) |
| JIS H4160 | Japanese standard for aluminium and aluminium alloy foils |
| GB/T 3198 | Chinese national standard for aluminium and aluminium alloy foil |
| RoHS / REACH | Restrictions on hazardous substances in coatings and materials |
For coated foil, also agree coating tests: adhesion, coating weight, contact angle, salt spray, oil resistance and odour. These are normally defined in the coil maker's own specification rather than in the base foil standard.
The main types of 8011 air-conditioner foil
| Type | Temper | Thickness (mm) | Width (mm) | Best for |
|---|---|---|---|---|
| Bare (uncoated) | O, H22 – H26 | 0.08 – 0.2 | Up to about 1800 | Indoor and dry-climate coils, lowest cost |
| Hydrophilic | H22, H24, H26 | 0.08 – 0.15 | 100 – 1800 | Evaporators and humid climates |
| Hydrophobic | H22, H24, H26 | 0.08 – 0.15 | 100 – 1800 | Refrigeration, frosting conditions |
| Corrosion-resistant coated (blue, gold, black) | H22, H24, H26 | 0.08 – 0.15 | 100 – 1800 | Outdoor, coastal and industrial condensers |
Hydrophilic foil
The coating makes water spread into a thin film that drains, preventing droplet bridging. Air resistance and fan noise fall and capacity is maintained in wet conditions. Costs more than bare foil.
Hydrophobic foil
A high contact-angle surface makes condensate bead and run off fast, helping defrost and limiting water carry-over. Used in refrigeration and some precision cooling units.
Coated foil
Epoxy, polyester, PE or PVDF-type coatings in colours such as gold, blue or black protect against salt, pollutants and chemicals. Heavier coatings (for example 10 – 14 µm) are used on duct and pipe applications in harsh environments.
Coil and packing specification
Typical coil details
- Core inner diameter
- 75, 150, 200, 300 or 500 mm
- Coil outer diameter
- Up to about 1200 mm, or to your decoiler limit
- Core material
- Aluminium, steel or paper
- Splices
- Limited number per coil and clearly marked
- Edges
- Clean slit edges without burrs, tight winding, minimal telescoping
- Packing
- Moisture-proof film with desiccant, eye-to-sky or eye-to-wall on pallets, wooden cases for export
How to choose the right 8011 foil
| Situation | Recommended type | Why |
|---|---|---|
| Indoor unit, low humidity, cost-driven | Bare or hydrophilic | Little condensate or corrosion risk |
| Evaporator in humid climate | Hydrophilic | Drains condensate, keeps airflow and capacity |
| Refrigeration evaporator, frosting | Hydrophobic | Water sheds fast, easier defrost |
| Outdoor condenser near the coast | Gold or blue corrosion-resistant coated | Resists salt deposits |
| Industrial or polluted atmosphere | Heavier epoxy-type coating | Resists acids and pollutants |
| Need thinner or stiffer fins | Consider 8006 instead of 8011 | Higher strength at the same gauge |
Temper choice. H22 gives the best collar-forming ability for standard designs; H24 and H26 add stiffness for thin or narrow-pitch fins but tolerate less collar height. O temper is used for bare foil formed into deep shapes.
Total cost. Coated foil costs more per tonne, but it can extend coil life considerably in coastal and humid regions and keep capacity from falling as the unit ages. Evaluate it over the expected service life, not the purchase price alone.
Quality checks for 8011 AC foil
- Chemistry: spectrometer analysis confirming 8011 limits for each cast
- Mechanical properties: tensile strength and elongation to the agreed standard for the temper
- Thickness: gauge checks across width and length to keep fin weight and heat transfer consistent
- Surface: no scratches, pinholes, oil stains, blisters or coating voids
- Coating: weight, adhesion, uniformity and contact angle
- Corrosion: salt-spray testing of coated foil for agreed hours
- Certification: EN 10204 3.1 certificate with results per lot
8011 foil tape and flexible duct foil
8011 foil is also the base for two common HVAC accessories. Aluminium foil tape combines thin foil with a pressure-sensitive adhesive to seal duct joints, insulation seams and pipe connections, giving a vapour barrier that reflects heat. Flexible duct foil is laminated and spiral-wound with a wire helix into flexible air ducts that are easy to cut and install without special tools. Both use soft O-temper foil for conformability. See our aluminium foil tape guide for details.
References and standards
- EN 546-2 – Aluminium and aluminium alloys: foil, mechanical properties
- EN 683-2 – Aluminium and aluminium alloys: finstock, mechanical properties
- EN 573-3 – Chemical composition and form of wrought products
- JIS H4160 – Aluminium and aluminium alloy foils
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits
8011 air-conditioner aluminium (aluminum) foil: frequently asked questions
Why is 8011 used for air-conditioner fins?
It forms tall fin collars easily, conducts heat well and is cheaper than manganese- or magnesium-bearing alloys. Its iron and silicon content gives a little more strength and a finer grain than pure aluminium foil.
What thickness of 8011 foil is used for AC fins?
Typically 0.08 – 0.2 mm, with about 0.095 – 0.15 mm most common for residential units.
Hydrophilic or hydrophobic: which is better?
Neither is better in general. Hydrophilic foil spreads condensate into a draining film and is standard for AC evaporators; hydrophobic foil beads water so it runs off, which suits refrigeration and frosting conditions.
What do gold and blue coated fins do?
They are corrosion-resistant coatings that protect outdoor coils from salt and pollutants. The colour helps identify the coating and check coverage.
What is the difference between 8011 and 8006 fin foil?
8006 contains more iron plus manganese, so it is stronger at the same thickness and allows thinner fins or taller collars. 8011 is more economical and adequate for most standard coils.
Which temper of 8011 should I order?
H22 for standard collar heights, H24 or H26 for stiffer, thinner fins, and O for bare foil formed into deep shapes. Confirm with a press trial when changing temper.
Buying 8011 AC foil?
Send thickness, width, temper, coating and coil details. We will reply with availability, test documents and a delivered price.
