Refrigerant is a chemical used in air cooling systems, such as the air conditioning system in a vehicle, to reliably change state from a liquid to a gas and back again, moving heat energy efficiently.
This involves chemical names, terms, and/or reactions, which may be complicated without a basic understanding of chemistry.R-12 Refrigerant
R12 refrigerant was the first standardized type of refrigerant, developed and first used in the 1930s. It was began being phased out worldwide in 1996, and was banned by most countries in 2010, now only used as a fire supressant in submarines and aircraft.
| ASHRAE Number | R12 |
| IUPAC Chemical Name | Dichlorodifluoromethane |
| Cylinder Color | White |
| Molecular Formula | CCl2F2 |
| GWP | 10,200 |
R-134A Refrigerant
The refrigerant R134A was developed as a replacement for R12, due to R12's environmental impact. It is also known as 1,1,1,2-Tetrafluoroethane.
| ASHRAE Number | R134 |
| IUPAC Chemical Name | 1,1,1,2-Tetrafluoroethane |
| Cylinder Color | Light Sky Blue |
| Molecular Formula | C2H2F4 |
| GWP | 1,430 |
R-744 Refrigerant
The refrigerant R744 is just carbon dioxide, but given a designation so that systems and products could be easily identified. CO2 systems need to operate at pressures starting at 60 bar, and of up to 130 bar (1880 psi), so even though CO2 refrigeration systems have been around for decades, they typically haven't been applied to vehicles until recently.
MAHLE R744 Refrigerant System
| ASHRAE Number | R744 |
| IUPAC Chemical Name | Carbon Dioxide |
| Cylinder Color | Light Green |
| Molecular Formula | CO2 |
| GWP |
R-1234YF Refrigerant
Chemically known as 2,3,3,3-Tetrafluoropropene, HFO-R1234YF has much less global warming potential than R134A.
A variant called R1234ZE (1,3,3,3-Tetrafluoropropene) is also available.
Handling of R1234YF
This video by Honeywell explains how to properly handle their R1234YF containers. This only shows how the container's gas is transferred into the machine that connects to the vehicle, not adding the refrigerant into the vehicle.
| ASHRAE Number | R1234YF |
| IUPAC Chemical Name | 2,3,3,3-Tetrafluoropropene |
| Cylinder Color | White with Red |
| Molecular Formula | C3H2F4 |
| GWP | 4 |
R-451A & R-451B Refrigerants
R451A and R451B are proposed mixes of about 10% R134A and 90% R1234YF, aimed at reducing flammability of the pure R1234YF formulation.
| ASHRAE Number | R451A/R451B |
| IUPAC Chemical Name | TBD |
| Cylinder Color | Not Yet Assigned |
| Molecular Formula | TBD |
| GWP | 147 |
- Automotive Air Conditioning Systems
- AC Compressor
- Air