The answer may not be so easy.  According to recent (early 1999) industry news, there may not be enough HFC-134a (R-134a) to go around.  Early warnings from the European market have begun, where supplies have tightened severely.  This situation could easily spill over into the US mobile A/C market, where demand is very strong. 

An estimated 50 million cars will need supplies of R-134a and R-12 to keep their cooling systems operating between now and 2006, according to a federal study.  Another indicator of this situation is the recent price hike of R-134a.  With an anticipated shortage, the price has gone up by 50% over last year's (1998) prices.

The shortage can be traced back to a problem with the supply of precursor chemicals like trichlorethylene in the manufacture of the refrigerant.  HVAC markets may not experience the same shortage as the MVAC market where many chiller manufacturers have contracts with R-134a suppliers.