A new standards revision will in future allow a larger charge of flammable A3 refrigerant, like propane (R290), in domestic air conditioners, heat pumps and dehumidifiers. The landmark revision of the safety standard IEC 60335-2-40, which previously limited charge sizes to, typically, 334g for an A3 refrigerant in a standard-sized split system in a standard size room, was finally approved on 29 April 2022, after a six-and-a-half-year revision process.
“The new Edition of IEC 60335-2-40 will enable R290 to be used in many AC and heat pump systems, which were previously blocked from using this refrigerant by the outdated version,” commented Asbjørn Vonsild, the convenor of Working Group 21 of SC61D, who shepherded the safety standard through its revisions.
For systems with A2L refrigerants and several indoor units, the current charge limits are already complex to take additional safety measures into account. The overall structure is not changed, but the allowed amount of A2L charge is increased. For instance, for an R32 system with a 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.
The revised safety standard allows for using a larger charge of flammable refrigerants (up to 988g of R290 in a standard split AC system) in new equipment designed according to certain additional safety requirements to ensure the same high level of safety as equipment using non-flammable refrigerants.
Clare Perry, climate campaign leader for the Environmental Investigation Agency, described the revision as “a critical milestone” on the pathway to net-zero.
“With this new standard, we expect the European Parliament and EU member states to recognise that HFCs are no longer needed for a large portion of the AC and heat pump market and to strengthen the recently proposed EU F-gas regulation accordingly,” she said.
The new standard is expected to be published on the 24 June. Countries will then need to swiftly adopt the revisions into their national legislation.
Source: Cooling Post