Another change you need to be aware of is the phase out of R-22, the refrigerant most commonly used in today's air conditioners and heat pumps. By 2010, all new air conditioners and heat pumps will be required to use non-ozone-depleting environmentally sound refrigerant, such as Puron Refrigerant.  This phase out has been mandated in an effort to help protect the Earth's ozone layer. By making the change to Puron Refrigerant now, you can protect yourself from the potentially higher future costs of servicing an air conditioner or heat pump that uses R-22.