Last year, building owners in the United States replaced or converted about 2,600 comfort cooling chillers that use chlorofluorocarbons (CFCs), according to the Air-Conditioning and Refrigeration Institute (ARI). Due to concerns about the depletion of the Earth's protective ozone layer, CFC refrigerants were banned from production in the United States on December 31, 1995.

Approximately half of the 80,000 large tonnage liquid chillers using CFCs from the early 90s have been converted or replaced since the phaseout began. Institutions that use chilled water for temperature and humidity control include malls, offices, hospitals, airports, factories, sports complexes and government buildings.

The pace for replacement and conversion slowed in 2002. An annual survey of chiller manufacturers released by ARI showed the slowdown was due to the weak U.S. economy last year. According to the survey, manufacturers expect chiller conversions to drop slightly in 2003 compared to 2002, but expect replacements to increase by 15%.