According to Alfa Laval, the future of refrigeration will probably revolve around natural refrigerants such as ammonia which do not constitute a threat to the ozone layer or add to the risk of global warming. To this end, they have developed a range of industrial refrigeration products designed to exploit the natural benefits of ammonia.
The first of this new breed of ammonia friendly heat exchangers is the Airmax 11 NH3 unit cooler which is designed for use in medium to large cold stores and refrigerated food preparation areas. Featuring a new frame design and coil, the range includes units with capacities ranging from 18 to 160 kW all designed for maximum energy efficiency and the lowest possible refrigerant charge.

The secret of this efficiency apparently lies in the coil pitch, the 16mm stainless steel tubes and the aluminium fins which provide the actual heat transfer surface. The units can be supplied with four different fan diameters (500, 560, 630 and 800) all of which work comfortably at temperatures as low as – 40ºC.