Low charge packaged ammonia refrigeration systems.

Ammonia has been used as a refrigerant for over 100 years. Traditionally this has been in industrial applications where the system is built on site with distributed pipework and a large refrigerant charge. The phase down of global warming HFC refrigerants under the EU F-Gas regulation will require the development and application of new refrigerants and systems. This provides an opportunity for the wider use of ammonia, particularly in smaller scale applications. Concerns with toxicity and flammability need to be addressed, along with increased capital cost. This paper looks at the definition of ‘low charge’ and recent developments in system design and technology aimed at reducing charge. A number of different system types are discussed along with component design and selection. These include both site built and factory packaged system.