Modern, low charge ammonia systems for the cold chain.

The phase out of ozone depleting refrigerants and increasing legislative pressure on the use of HFC refrigerants has resulted in greater interest in the use of ammonia for temperature controlled storage/ distribution and food production worldwide. Ammonia systems have traditionally had large cooling capacities and tonnes of refrigerant charge. With more end users now considering the switch to ammonia, concerns have been raised over its toxicity and flammability and this has led to the development of low charge solutions for both chill and low temperature applications. This paper looks at what the term ‘low charge’ means for ammonia systems, the drivers behind moving to low charge over traditional systems and the solutions that are available for use in the cold chain.