Geothermal heat pumps on the market today use modern refrigerants. The Environmental Protection Agency considers this refrigerant as part of the interim solution to the CFC issue.
Field connections of refrigerant piping are potential sources of leaks. No field connections are required with geothermal heat pump systems. They are sealed at the factory, just like your refrigerator.
The ground loop is made of durable high-density polyethylene pipe, which carries a warranty of 20 to 50 years. This helps eliminate the possibility of leaks into a nearby water table. The same type of pipe and pipe fusion methods have been safely used for more than 30 years in natural gas distribution systems.
Chemically, HCFC-22 is chlorofluoromethane, CHCIF2. No health or safety concerns have been identified; it is classified in the A1 Safety Group, the safest group, in the American National Standard ANSI/ASHRAE 34-1992.
The toxicity group A indicates no toxicity identified at concentrations of less than or equal to 400 parts per million. Group 1 indicates there is no flame propagation.
As with any refrigerant, it should be handled carefully. It should never be vented to the atmosphere, and all equipment should be properly installed and maintained by a certified technician.
Learn more about: Refrigerant regulatory history and HCFC-22 alternatives