To keep indoor spaces cool and comfortable, air conditioning systems force chilled air through your home's ventilation system with a series of fans and duct work. To cool the air, the system uses a chemical compound known as refrigerant or coolant. The coolant is mixed with air inside an air handler unit, a big box outside of your home. There are different kinds of refrigerant with different chemical formulas and properties, including R134.
All refrigerants have a distinctive R-number that identifies them. R134 is a member of the more recent generation of hydrofluorocarbon (HFC) refrigerants that has replaced older, ozone-depleting chemicals, such as R22 and R12. R134 was specifically designed to replace R12 used in smaller air conditioning units, such as those used in vehicles. R134 is also used in home appliances, mobile refrigeration units and stationary commercial units, such as cold cases in grocery stores.
R134 is manufactured and sold by DuPont under the trademarked name Suva. The trademark label itself reads: "Refrigerant for Automotive Air Conditioners." It was not designed for use in residential air conditioning systems. In addition, the potential for this coolant to generate greenhouse gases has prompted laws, which will require 2017 model-year cars and beyond to use HFO-1234yf, a replacement coolant.
Refrigerants are not always compatible, and retrofitting air conditioning systems with the wrong coolant can cause a variety of problems, including leaks, malfunctions and total system failure. In addition, handling coolant can be a hazardous activity; the contents of refrigerant containers and air conditioning systems are kept under high pressure, and technicians must be careful to use the correct couplings, hoses and valves to avoid dangerous accidents.
DuPont designed 407c and 410a refrigerants as the HFC replacements for R22 coolant used in home air conditioning systems. These coolants match R22 in terms of energy efficiency and are superior to R134; however, 410a cannot be used in a retrofit -- it must be installed as part of a new system, whereas 407c can. R22 cannot be used in new systems, but the Environmental Protection Agency, which issues regulations regarding ozone-depleting chemicals, does not require retrofitting older equipment.