With updated global safety standards for domestic appliances that allows for higher charge limits of propane (R290) and other flammable refrigerants, heat pumps up to 70kW (19.9TR) no longer require f-gases, according to Ingo Seliger, Head of Standardization for Public Affairs at German manufacturer Viessmann Group.

“For the residential market, it’s absolutely clear that we don’t need f-gases anymore,” he said, adding that the approval of safety standard IEC 60335-2-40 ED7 removes all barriers to the adoption of propane heat pumps.

“For the residential market, it’s absolutely clear that we don’t need f-gases anymore.”

Ingo Seliger, Viessmann

Seliger delivered his remarks during his presentation in the heat pump market trends session at the ATMOsphere (ATMO) Europe Summit on natural refrigerants. The conference took place November 15–16 in Brussels and was organized by ATMOsphere, publisher of Hydrocarbons21.com.

Safe use of higher charges

The updated standard, which was unanimously approved by an International Electrotechnical Commission (IEC) subcommittee in May 2022, is expected to accelerate the shift from high-GWP HFCs to flammable refrigerants like R290 in ACs and heat pumps.

“[It] provides for safe use of sustainable natural refrigerants indoors and outdoors, including R290,” said Seliger.

Two of the main updates relating to R290-based air-to-water heat pumps – also known as hydronic heat pumps – are that the new standard allows for higher charge limits and multiple circuits with multiple charges within each appliance, he explained.

IEC 60335-2-40 ED7 also stipulates new rules around refrigerant leakage – or “releasable charge” – which can be limited by safety shut-off valves, leak detection systems and the use of particle foam material to trap any leaked refrigerant within the housing of the heat pump.

“Natural refrigerants, propane in particular, are a safe and sustainable alternative to f-gases,” said Seliger. “R290 has been used safely for 20 years [and] R290 heat pumps are especially well suited for operation conditions in the building stock,” he added, noting that they are at least on par with f-gas heat pumps in terms of energy efficiency.

“Natural refrigerants, propane in particular, are a safe and sustainable alternative to f-gases; R290 has been used safely for 20 years.”

Ingo Seliger, Viessmann

While IEC 60335-2-40 ED7 has been approved as a global standard, individual countries or regions need to officially adopt it for it to take effect.

Last year, at the ATMO World Summit on March 30 (organized by ATMOsphere) Asbjørn Vonsild, head of Vejle, Denmark-based Vonsild Consulting, explained the process by which the IEC 60335-2-40 ED7 standard would be adopted in the EU.

The primary method is for the European Commission (EC) to publish EN 60335-2-40 ED7 as a “harmonized standard,” which he said would take two to three years. In the meantime, equipment manufacturers could apply the higher charge limits of the new standard by using a “risk assessment – a simple argument that a new edition of a harmonized standard will be at least as safe as an old (ED6) standard,” said Volsild.

Europe has another EN standard, EN 378, that allows up to 1.5kg (3.3lbs) of R290 indoors, but it is less suitable for factory-built systems – the majority of home ACs and heat pumps – and has stricter room size requirements. EN378 is also in the process of getting updated.

In the U.S., the next step will be forming a CANENA Technical Harmonization Committee (THC) to discuss proposals for adopting the changes into the next edition of the North American safety standards, including UL 60335-2-40, explained Christina Starr, Senior Policy Analyst, Climate Campaign, for the Washington, D.C.-based Environmental Investigation Agency (EIA).

Propane heat pumps for REPowerEU

According to Seliger, ambitious f-gas regulation will help Europe achieve its heat pump targets under the REPowerEU plan.

To ensure independence from Russian oil and gas imports, the EU aims to have 30 million heat pumps installed across the region by 2030.

To support Europe’s ambitions, Viessmann has committed to invest €1 billion (US$1.07 billion) in heat pumps and other green climate solutions over the next three years. The company also plans to open a new production site in Legnica, Poland, that will focus on high-efficiency, propane (R290)-based heat pumps. The facility is due for completion later this year.

In addition to Viessmann’s efforts, several other manufacturers of hydronic heat pumps are investing heavily in the development and production of new models to meet demand, Seliger said.

HFOs are not ‘future-fit’

During his presentation, Seliger called for consistency across all of Europe’s environmental targets and strategies to “provide legal certainty for transformation to sustainable heat pumps without environmentally harmful chemicals.”

As the EU works to phase down high GWP HFCs while simultaneously ramping up the deployment of heat pump technologies, some manufacturers are turning to environmentally-harmful HFOs as the solution.

However, Seliger stated that HFOs are not “future-fit” due to their threat to human and environmental health.

“HFOs are not future fit.”

Ingo Seliger, Viessmann

“HFOs are not needed to achieve the heat pump ramp-up and reduction of GHG emissions from refrigerants in tandem,” he added. “A quick shift towards R290 in ‘mass market’ hydronic heat pumps without any detour via HFOs enables the decarbonization of the building sector without harmful environmental impacts.”