Air conditioning: towards a relaxation of the rules for the use of flammable refrigerants

While the European Commission is paving the way for the use of flammable refrigerants as an alternative for split systems, the current revision of the international standard IEC 60335-2-40 should allow higher charges of these refrigerants in air conditioning.

At the European level


The European Commission has published a report (1) entitled “The availability of refrigerants for new split air conditioning systems that can replace fluorinated greenhouse gases or result in a lower climate impact”.


The report lists the “most relevant” alternative refrigerants that can be used in new "split" (single-split and multisplit systems) air conditioners, instead of R410A, which has a GWP of 2088:


  • A1 (non-flammable): R466A (PRP 733),
  • A2L (mildly flammable): R32 (PRP 675), and R452B (PRP 698),
  • A2 (flammable): R152a (PRP 140).
  • A3 (highly flammable): R290 (propane) (GWP 3); R1270 (GWP 2).


The report focuses on R290 because of its very low GWP, and because it is already used in split systems with cooling capacity under 7 kW since 2012, in China and India.


The energy efficiency and cooling capacity of these air conditioners is equivalent to that of devices using conventional refrigerants.


The report indicates that the use of R290 allows a 50 % reduction in charges compared to conventional refrigerants such as R410A, which involves a reduction in costs.


The report concludes that it is therefore technically possible to use propane in new split air conditioners with a cooling capacity of less than 7 kW, if permitted by national laws.


This report will be part of the assessment and proposals for amending the F-Gas regulation.


At the international level


At the international level, a recent GIZ webinar provided an update on the progress of the revision of the IEC 60335-2-40 standard for room air-conditioning systems, heat pumps and dehumidifiers, which specifies, among other things, the authorized charges when using flammable refrigerants.


Asbjørn Vonsild, convener of the working group (WG21) in charge of developing additional requirements (charge limits, ventilation systems, gas detectors, etc.) for A2L, A2 and A3 refrigerants, specified that a proposal (61D/CDV) was released on August 7, 2020. Member countries represented on the IEC’s sub-committee 61D will have until October 30 to vote on the proposal. (2)


Regarding A3 flammable refrigerants such as R290, the main changes proposed concern the charge permitted in a standard size room. The current maximum charge for an A3 refrigerant such as R290 for a standard split system in a 20m2 room with 2.2m ceiling height is set at 334g. In a room of similar size, the new proposal would allow up to 988g of R290 with a more robust design of system, increased airflow, leak detectors and safety shut-off valves. (3)


For systems with A2L refrigerants and several indoor units, the allowed charge is increased. For instance, for an R32 system of robust design serving three rooms with ceiling-mounted units, each room being 15m2 with a ceiling height of 2.2m, the current standard allows 2.5 kg of R32 if no additional safety measures are applied. With the new proposal, this limit will be 7.5kg. (3)


Based on the comments received on the 61/CDV proposal, a final draft will be put to the vote in July 2021. The 7th edition of IEC 60335-2-40 standard should be published at the end of 2021. However, after the revised standard is published, regional and national standards bodies will need to adopt it before it can enter into force in the corresponding markets.



1 The availability of refrigerants for new split air conditioning systems that can replace fluorinated greenhouse gases or result in a lower climate impact: link.

2 Hydrocarbons21 IEC Releases Proposal for Boosting Hydrocarbon Charges in Room ACs

3 Cooling Post Safety update could unlock flammable refrigerant use