Pure Cooler

The Alfa Laval Pure Cooler is a single-pass dry expansion evaporator for commercial and industrial refrigeration cooling applications with evaporation temperatures ranging from 0°C to +10°C. The Alfa Laval Pure Cooler has been optimized for R134a and R1234ze refrigerants at low pressure (16.5 barg). Capacity range 100 - 1750 kW. PED/CE, ASME, EAC, SELO, DNV and other major marine approvals are available. The Alfa Laval Pure Cooler replaces the Alfa Laval Dry-E product line.

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Innovative low-pressure dry-expansion evaporator

The Alfa Laval Pure Cooler is an innovative dry-expansion evaporator that delivers high efficiency at pressures as low as 16.5 bar. With its fixed tube sheet design, this shell-and-tube heat exchanger optimizes air-conditioning and process cooling applications using R134a refrigerant and handles fluid temperatures from +50°C to -10°C. New features raise efficiency and contribute to reduce total cost of ownership.

Up to 30% increase in cooling efficiency

The Alfa Laval Pure Cooler shell-and-tube evaporator features a patented refrigerant distribution system and a single-pass, counter-current design. Inner grooved tubes maximize the R134a heat transfer coefficient and limit the negative effects of refrigerant pressure drop.

These features, in combination with the heat exchanger’s capability of operating at higher evaporating temperatures of up to 5°C, raise heat transfer efficiency by up to 30% compared to conventional shell-and-tube heat exchangers. This maximizes performance and reduces costs.

Better energy and building efficiency

The Alfa Laval Pure Cooler is the dry-expansion solution that meets:

  • the ASHRAE 90.1 standard
  • the International Energy Conservation Code
  • the U.S. Green Building Council’s LEED

As a cooling system component with a coefficient of performance that is greater than 5 (COP > 5), the Alfa Laval Pure Cooler dry-expansion evaporator offers highly efficient performance that approaches to flooded evaporator systems. Its high efficiency provides measurable energy savings compared other evaporator solutions.

Less downtime for maintenance

Its shell-and-tube evaporator design makes the Alfa Laval Pure Cooler resistant to scaling and fouling when operating with brine or water of low quality. In addition, this dry-expansion evaporator features specially designed plastic baffles that improve the water-side performance and prevent corrosion issues.

Compact, high-capacity dry-expansion evaporator

The Alfa Laval Pure Cooler is 20% smaller in diameter, yet delivers a cooling efficiency that is higher than comparable high-capacity solutions. This makes Alfa Laval Pure Cooler a compact and economical choice for cooling, which makes good use of the available space.

Dry-expansion evaporator supply and delivery

The Alfa Laval Pure Cooler is available in several different models with capacities up to 1750 kW. A high-pressure unit for heat pump applications is available upon request. Contact your Alfa Laval representative for more information.


  • Compact design vs equivalent products in the market
  • Performance guarantee by Alfa Laval lab test
  • Low environmental impact: CO2 emission -52% vs equivalent products in the market
  • Configurable online: contact Alfa Laval local sales organization to get the login


  • ASME, EAC, SELO, DNV and other major marine approvals available upon request
  • Mounting feet (recommended)
  • Vic-Flanges
  • Insulation
  • Heater cable

Zasada działania


The Alfa Laval Pure Cooler dry-expansion shell-and-tube evaporator consists of a shell (pressure vessel) containing a single-pass straight tube bundle with inner-finned tubes. It is primarily designed for use in low-pressure cooling systems that consist of a compressor, a condenser, an evaporator and an expansion valve.

Operating principle

The Alfa Laval Pure Cooler dry-expansion evaporator uses the well-known shell-and-tube heat exchanger principle to achieve the desired effect. The primary fluid, or refrigerant, flows through the tubes, while the secondary fluid (normally water or anti-freeze brine) flows over the tubes (through the shell) in order to bring about heat transfer from one fluid to the other.

The two-phase refrigerant arrives at the evaporator from the expansion valve. It then flows inside the tubes and evaporates as it absorbs heat from the surrounding secondary fluid, which is cooled down by this heat loss.

To achieve the most efficient cooling possible, the refrigerant is superheated in the final portion of the tube run to ensure that it reaches the compressor in vapour form. Specially designed baffles on the shell side boost heat transfer efficiency further.