In 2006, the refrigerant used depended on the type of air conditioning system: automotive A/C primarily used R-134a, while most home and commercial central air conditioning relied on R-22, with early adoption of R-410A in newer equipment.
Automotive air conditioning refrigerants in 2006
The automotive sector had already shifted away from ozone-depleting materials, and R-134a was the standard for new vehicles in many markets in 2006.
- R-134a (1,1,1,2-tetrafluoroethane) was the standard refrigerant in virtually all new passenger cars, replacing the older R-12.
- R-12 (dichlorodifluoromethane) had been largely phased out for new vehicles since the 1990s due to ozone depletion concerns; remaining R-12 systems required careful handling and retrofit options if serviced.
- R-1234yf existed as a planned future replacement with lower global warming potential, but it was not widely adopted in 2006.
- R-134a's high global warming potential (GWP) was a driver for later transitions toward lower-GWP options in subsequent years.
Overall, automotive A/C in 2006 was dominated by R-134a for new vehicles, with R-12 largely retired from new production and R-1234yf not yet commonplace.
Residential and commercial air conditioning refrigerants in 2006
The residential and commercial central A/C market was still predominantly using R-22, with some newer equipment beginning to incorporate R-410A.
- R-22 (chlorodifluoromethane) was the prevailing refrigerant for most existing home and commercial central air systems built before the shift away from HCFCs.
- R-410A (a blend of R-32 and R-125) was being adopted in newer equipment, especially higher-efficiency models, but did not yet dominate the market in 2006 due to the need for compatible equipment and higher operating pressures.
- R-134a was used in some smaller or non-central applications, but it was not the standard for typical residential central AC in 2006.
- Regulatory pressures under the Montreal Protocol and related U.S. EPA rules aimed to reduce HCFC use led to the gradual phase-out of R-22 for new equipment, with continued service coverage for existing systems.
In summary for residential/commercial systems, R-22 was the common refrigerant in 2006, with R-410A beginning its transition in newer installations.
Summary
The refrigerant landscape in 2006 varied by application. Automotive air conditioning relied on R-134a as the standard, replacing older R-12, while home and commercial central air largely depended on R-22, with early adoption of R-410A in newer equipment. This period reflected ongoing environmental regulations and market transitions that would accelerate in the following decade, reshaping which refrigerants were used in new systems and how older systems were serviced.