What is low-charge ammonia?
The term low-charge ammonia is being bandied around a lot in the heating and cooling industries these years, but what does it mean?
Ammonia (NH3/R717) has been used as a refrigerant for nearly 150 years. However, being a toxic substance, it can be dangerous to human health if leaked into a closed environment. This may limit the adoption of this otherwise very energy-efficient – and environmentally friendly – refrigerant in many cooling applications.
In recent years the use of ammonia in refrigeration has become safer thanks to research and technological innovation. These efforts have reduced the refrigerant charge needed in systems, without sacrificing cooling capacity or energy efficiency. This new technology is commonly referred to as low-charge ammonia refrigeration. So, low-charge ammonia essentially means to lower the charge or amount of refrigerant used within a refrigeration circuit.
U.S. industry groups Global Cold Chain Alliance (GCCA), International Association of Refrigerated Warehouses (IARW) and the International Association for Cold Storage Construction (IACSC) classify three types of ammonia technology as low-charge:
• Optimized traditional system, which use enhanced controls or evaporators to lower the charge of ammonia,
• Packaged systems, which are normally installed on the roof of a facility,
• Hybrid systems, which use CO2/NH3 in tandem to lower the charge.
These three types of low-charge ammonia technology have been installed in food processing, food storage, data centers and pharmaceutical facilities, along with supermarkets and commercial air conditioning.
Read more about it in the World Guide to Low-Charge Ammonia below. The guide looks at trends in different parts of the world, and provides a detailed overview of how the industry defines “low-charge” technology. It also highlights key characteristics of ammonia as a refrigerant, and outlines the 150-year history. The last section includes application examples from around the world, and concludes with an analysis of drivers and major challenges in today’s market.