It occupies several dozen buildings of varying ages and types in a campus setting in Durham, North Carolina. Recently, HVAC foreman Louis Maness was considering options for a CFC-11 chiller in the medical center's Sands Building. It was one of two chillers for the building. Facilities with CFC-11 chillers are facing challenging times. Strict new international standards prohibit the manufacture of CFC-11 refrigerants in developed countries, and both international guidelines and national environmental regulations disallow significant refrigerant emissions.
Owners essentially have three choices.
They can replace older chillers with tight, new machines with acceptable alternative refrigerants. This approach has the advantage of assuring regulatory compliance and achieving the higher efficiency now available in new chiller designs. Another approach is to upgrade an existing chiller to meet current refrigerant containment requirements. This normally involves a complete unit overhaul to eliminate possible leaks and replacement of the purge. This approach is the least expensive initially and makes sense for machines that have limited remaining life and cannot readily be retrofitted to alternative refrigerants.