Beginning January 1, 2010: New refrigeration and air conditioning systems will not longer be able to be manufactured using R-22 as the refrigerant.
R22 will still be available for existing products. However, this is only until 2020. After 2020, R22 will no longer be produced.
The #1 alternative to R22 is R410a. You can get a new system or convert to R410a with a makeover. This is not a simple matter of putting in a new refrigerant. R410a has a much higher discharge pressure. Your R22 system is not rated for the pressure of R410a. A system change from R22 to R410a will probably require considerable change. However, a system change or changing to a new system with R410a is appropriate.
Although a lot of manufacturers would prefer that R22 be completely off the market, to be competitive and not give market share, nearly all manufacturers are continuing to sell the R22 units.
This is an individual call. We all know converting to an R410a hvac system is the environmentally responsible thing to do. However, we also have to look at each individual situation. I will continue to service R22 units until 2020 and no more R22 coolant is available.