Special industrial air coolers, fully designed to customers' specifications.     Apart from the standard ranges of industrial and commercial air coolers, Alfa Laval produces special Helpman air coolers fully designed to customers’ specifications. For these special air coolers there are four basic coil types available (Helpman ZT, ZTY, TR & TRY) and a large number of accessories and design options. - Evaporating temperatures : down to -45°C - Refrigerants : ammonia (R-717), all H(C)FC, brine, CO2 - Capacities : as required