What Temperature Ranges Are Frost-free Aluminum Evaporators Suitable For?

Frost-free aluminum evaporators are suitable for a broad range of refrigeration and freezing temperatures, depending on their design, fin spacing, and defrost configuration.

Typical Temperature Ranges

• Medium-temperature refrigeration:
  +5 °C to –5 °C
  Used in chilled rooms, food preparation areas, and fresh-produce storage where moisture control and uniform airflow are required.

• Low-temperature freezing:
  –18 °C to –25 °C
  The most common application range for aluminum frost-free evaporators, including walk-in freezers, frozen food storage, and distribution cold rooms.

• Very low-temperature / quick-freeze applications:
  Down to –30 °C (occasionally –35 °C)
  Achievable with wider fin spacing, reinforced airflow, and properly sized electric or hot-gas defrost systems.

Practical Design Considerations

• Fin spacing: Wider fin spacing (e.g., 6–10 mm) is required at lower temperatures to limit frost bridging.

• Defrost method: Electric or hot-gas defrost is essential below –18 °C.

• Humidity and door openings: High moisture loads may reduce the practical minimum temperature unless defrost capacity is increased.

General Limitation

For applications below –35 °C to –40 °C, aluminum frost-free evaporators are less common. Stainless steel or specialized industrial evaporators are typically preferred due to structural strength, hygiene requirements, and extreme frost conditions.

In summary, frost-free aluminum evaporators are best suited for +5 °C down to approximately –30 °C, covering the majority of commercial and industrial freezer applications.