Ammonia (R-717 or NH3) is a natural refrigerant with a GWP of 0. Ammonia has been used in industrial cooling applications since the 1930s and is generally acknowledged to be the most efficient refrigerant, Ammonia is toxic so must be handled correctly.
Carbon Dioxide (CO2)
Carbon dioxide is a natural refrigerant with a GWP of 1. It is also a greenhouse gas, however the amounts used in HVACR equipment are comparatively small so that the global warming impact of the refrigerant is minimal.
Chlorofluorocarbons (CFCs) were the first generation of synthetic refrigerants and foam blowing agents. They are potent greenhouse gases and deplete the ozone layer and their use has been phased out since 2010 under the Montreal Protocol.
Global Warming Potential (GWP) is a measure of the amount of heat a greenhouse gas traps in the atmosphere over a given time period relative to carbon dioxide.
Hydrochlorofluorocarbons (HCFCs) are used as refrigerants, foam blowing agents and in industrial applications. They are both potent greenhouse gases and deplete the ozone layer, so are being phased-out globally under the Montreal Protocol.
Hydrofluorocarbons (HFCs) are powerful greenhouse gases with GWPs hundreds to thousands of times greater than CO2. They are frequently used as refrigerants in air conditioning and refrigeration and as foam blowing agents.
Hydrofluoroolefins are unsaturated HFCs developed as alternatives to HFCs for use in cooling applications.
HVACR stands for Heating, Ventilation, Air Conditioning and Refrigeration
Hydrocarbons, including propane (R-290), propene (R-1270) and isobutane (R-600a) are natural refrigerants with GWPs of 3, 2 and 3 respectively. Hydrocarbons are highly efficient but are A3 refrigerants, meaning they are flammable and must be handled correctly and in line with international standards.
Natural refrigerants are naturally occurring substances that offer climate friendly alternatives to synthetic F-gases. Natural refrigerants include ammonia, carbon dioxide, hydrocarbons, water and air and have zero ozone depleting potential and very low or zero global warming potential.
Ozone Depleting Substances
Ozone Depleting Substances (ODS) are gases that damage the ozone layer. ODS include CFCs and HCFCs used as refrigerants and in aerosols that are being phased out under the Montreal Protocol.