R-1234yf and its properties

This article serves as a helpful overview for operators of refrigeration systems that already use R-1234yf or, if necessary, have to be retrofitted to R-1234yf from the old R-134a refrigerant. It provides a basic description of R-1234yf and its properties. It also touches on the known issues with this fluorinated refrigerant.

Information about R-1234yf

R-1234yf is a refrigerant with a chemical designation of 2,3,3,3-tetrafluoropropene or HFO-1234yf. It is a hydrofluoroolefin (HFO) and thus a low-GWP refrigerant. It is a combustible gas that does not deplete the ozone layer and has a low GWP (global warming potential) value of 4. This advantage and its thermodynamic properties, which are comparable to those of R-134a, make R-1234yf a popular alternative to R-134a.

R-1234yf was controversial at its launch because of its – admittedly low – flammability and the hydrogen fluoride it produces during combustion. However, it is now used in the air-conditioning systems of almost all new passenger cars in the EU.

Current situation

Prices of R-134a have skyrocketed by as much as 400-plus percent as a result of Regulation (EU) 517/2014 (F-Gas Regulation) . The regulation requires a gradual reduction of high-GWP F-gases within the EU and a switch to more environmentally friendly refrigerants by 2030. This has made R-134a increasingly difficult to obtain as manufacturers switch to producing more environmentally friendly refrigerants that are not subject to volume restrictions.

However, as actual demand for R-134a continues (it can still be used in used vehicles), we can expect to see further substantial price increases as the refrigerant becomes scarcer and scarcer. We expect that consumers will increasingly switch to an alternative refrigerant.

R-1234yf as an alternative to R-134a

Since end consumers now pay more for R-134a (which used to be quite inexpensive) and have to pony up a lot for its alternative, R-1234yf, there is a risk of a gray area emerging in the repair, service and maintenance sector. It should be noted that the law requires car manufacturers to state which refrigerant they have used.

If a refrigerant other than R-134a is filled into the air-conditioning system, the vehicle’s type approval expires automatically. If, however, the type approval were to expire when converting to an alternative like R-1234yf, auto repair and maintenance shops might begin to switch to flammable hydrocarbons (e.g., propane or isobutane) at lower cost. The (illegally) filled agent might then be declared incorrectly, posing unforeseeable safety risks during future repair and maintenance work.

It is also not safe to use a flammable refrigerant (R-1234yf, hydrocarbons) instead of a non-flammable refrigerant (R-134a) in an existing system without taking further precautions.


R-1234yf will definitely become a more widely used refrigerant in coming years thanks to its low GWP value. However, its use should be carefully considered due to the aforementioned safety requirements (A2L safety classification) and potential environmental impact. Operators should obtain all the information they can about it in any case.

Next, have the CO₂ equivalent calculated and find out how often you need to check your system for leaks.

More information: The GWP value of refrigerants and its importance for operators

Use our GWP value calculator to easily find out what you need to do and find suitable alternatives.

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Regulation (EC) No 1005/2009 has banned the use of hydrochlorofluorocarbons since January 1, 2015. Urgent action is needed! The CO2 equivalent is below the limits that currently require regular leak testing. Nevertheless, as an operator, you should perform regular leak tests and maintenance to avoid risking machine breakdowns. CO2 equivalent is above the limits. In this range, regular leak testing (every %s months) is mandatory! In addition, there are record-keeping obligations regarding the charge size, the CO2 equivalent and the recycling or reclamation facilities.

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