The refrigerant transition is already under way

According to Graham Smith, the refrigerant transition is no longer something commercial heat-pump specifiers can treat as a distant concern.

“The industry has spent the past decade exploring alternative approaches, and every option has demanded a trade-off.”

Graham Smith, Applied Commercial Director UK&I, Carrier

Refrigerants including R410A, R32, lower-GWP blends, hydrofluoroolefins and natural refrigerants all bring different combinations of global warming potential, operating characteristics, system requirements and safety considerations.

Propane, known in refrigeration terminology as R290, has become one of the more prominent natural refrigerant options. Its 100-year global warming potential is approximately 0.02 under IPCC AR6 methodology, while it is not itself a fluorinated greenhouse gas.

That does not automatically make an R290 system the correct choice for every commercial project. Refrigerant selection still needs to be considered alongside heating capacity, design temperatures, seasonal efficiency, installation location, refrigerant charge, controls, safety requirements, service support and the wider building system.

For a broader independent explanation, see our R290 heat pumps guide.

Why manufacturers are moving towards R290

The move towards R290 is partly being driven by the continuing reduction in the use of higher-GWP fluorinated refrigerants.

European market data also points towards growing adoption. Heat Pumps Watch reported that R290 accounted for 38% of new EU residential heat-pump certifications in 2024, compared with 3% in 2021.

That figure relates to residential certification data rather than the commercial market, but it illustrates the speed at which propane-based heat-pump platforms have moved into the European mainstream.

Carrier says its own work on alternative refrigerants has included R32 and R290, with propane increasingly being used where its combination of low GWP, heating performance and higher-temperature capability suits the application.

R290 does involve a genuine safety trade-off

The principal characteristic that cannot be ignored is flammability.

R290 is classified as an A3 refrigerant: low toxicity with high flammability. That makes it fundamentally different from an A1 non-flammable refrigerant and means equipment and installation requirements must be designed around the properties of propane from the outset.

Smith argues that the relevant question is therefore not whether R290 has a hazard, but how that known hazard is engineered and managed.

“Flammable does not mean unmanageable. The key is not the absence of risk, but the presence of well-developed standards, engineering controls and training.”

Graham Smith, Carrier

This distinction matters. A move towards lower-GWP refrigerants should not encourage specifiers or building owners to treat all refrigerants as interchangeable. Equipment design, charge size, positioning, ventilation where required, potential ignition sources, access for servicing and manufacturer instructions all need to form part of project-specific assessment.

Safety needs to be engineered into the equipment

Carrier says its approach is to design the equipment specifically around the characteristics of R290 rather than adapting a conventional refrigerant system and treating propane safety as an additional feature.

The company points to measures including the arrangement of refrigerant-containing components within dedicated enclosures and the consideration of refrigerant detection, charge quantities and appropriate system protection.

Relevant refrigeration and heat-pump safety standards include EN 378 and IEC 60335-2-40. Their application depends on the equipment and installation, so they should be considered as part of competent project design rather than reduced to a simple checklist.

The same principle applies to installation and servicing. Personnel working with R290 systems need appropriate knowledge and training for flammable refrigerants and must follow the equipment manufacturer’s installation and service requirements.

Carrier’s AquaSnap 61AQ provides one commercial example

One example of Carrier’s move towards propane is the AquaSnap 61AQ, a commercial air-source heat pump using R290.

Carrier currently publishes a heating-capacity range of approximately 40–140kW for individual 61AQ units, with modular configurations available for larger outputs. The manufacturer also states that the unit can produce water at up to 75°C within defined operating conditions.

Those figures describe the manufacturer’s operating envelope; they should not be interpreted as evidence that every commercial heating system should operate at its maximum water temperature.

Higher flow temperatures can help with some boiler-replacement, radiator and domestic-hot-water applications, but increasing the required temperature lift can reduce heat-pump efficiency. The correct design target is therefore normally the lowest practical system temperature capable of meeting the building’s demand.

See our guides to commercial air source heat pumps and commercial heat-pump design and installation for the wider system considerations.

What do the 2027 F-gas changes actually mean in the UK?

This is where the distinction between Great Britain, Northern Ireland and the European Union is important.

European Union

Regulation (EU) 2024/573 introduces progressively tighter restrictions on fluorinated greenhouse gases in new air-conditioning and heat-pump equipment.

From 1 January 2027, the regulation restricts fluorinated greenhouse gases with a GWP of 150 or more in several categories of new self-contained heat pumps, including monobloc and other self-contained systems up to 50kW, subject to specified safety exceptions. Further restrictions follow for other equipment categories.

Great Britain

The EU’s 2024 regulation should not be treated as though it automatically applies in England, Scotland and Wales.

Great Britain operates its own F-gas regime. Defra consulted on changing the HFC phasedown from 2027, but in May 2026 confirmed that it would not legislate during 2026 to change the existing phasedown step taking effect from 1 January 2027.

GB therefore continues under its existing F-gas framework while the government considers longer-term reform. Existing GB restrictions already limit certain higher-GWP refrigerants in specified types of equipment, and the permitted quantity of HFCs placed on the market continues to be phased down.

Northern Ireland

Northern Ireland is different. Under the Windsor Framework, EU F-gas legislation continues to apply there, and DAERA confirms that Regulation (EU) 2024/573 applies directly in Northern Ireland.

What commercial specifiers should investigate

The direction of refrigerant policy makes long-term product support increasingly relevant, but refrigerant choice should remain one part of a wider commercial heat-pump assessment.

For an R290 project, useful questions include:

• What heating output is available at the project’s actual design conditions?
• What flow and return temperatures are required?
• What COP is available at those temperatures?
• What refrigerant charge does each circuit contain?
• What location and clearance requirements apply?
• What measures are required because R290 is an A3 refrigerant?
• How will the unit interact with existing emitters, hydraulics and controls?
• What training is available to the installation and service supply chain?
• What is the manufacturer’s long-term refrigerant and product strategy?
• What service and spare-parts support is available for the expected life of the system?

Our commercial heat-pump manufacturers guide looks at the wider criteria businesses and consultants can use when comparing suppliers.

R290 should not be reduced to either “safe” or “unsafe”

One of the more useful points in Carrier’s contribution is that the debate around propane can become too binary.

R290 is flammable. That characteristic should neither be hidden nor treated casually.

Equally, its use in purpose-designed equipment does not mean that a commercial R290 heat pump should automatically be regarded as unsuitable. The practical question is whether the risks have been addressed properly through product design, project design, installation practices, commissioning, maintenance and competent servicing.

“R290 isn’t being adopted because the industry has stopped worrying about safety. It’s being adopted because manufacturers have done the engineering work to make safety, performance and practicality compatible.”

Graham Smith, Carrier

That is ultimately a project-specific engineering question rather than something that can be answered simply by the refrigerant name on a specification sheet.

Heat Pump Guide UK view

R290 is clearly becoming an important refrigerant in both residential and commercial heat-pump development, and the regulatory direction in Europe gives manufacturers another reason to invest in propane platforms.

However, refrigerant choice should not become a shortcut for assessing the quality or suitability of a heat pump.

Commercial buyers and specifiers should still compare equipment at the temperatures and outdoor conditions the building will actually encounter, while considering capacity, efficiency, controls, noise, hydraulics, electrical infrastructure, safety constraints, installation quality and long-term service support.

For a wider introduction to these decisions, read our Commercial Heat Pumps UK guide.

About the contributor

Graham Smith

Applied Commercial Director UK&I, Carrier

Graham contributed Carrier’s perspective on refrigerant transition, R290 safety and the practical considerations surrounding commercial propane heat-pump systems.

The original editorial contribution and images were supplied by Carrier’s PR representatives and approved by Carrier before submission. Heat Pump Guide UK independently edited the article, checked key technical and regulatory claims and added UK-specific context. Publication does not constitute an endorsement of Carrier or the AquaSnap 61AQ.

Sources and further reading

• Department for Environment, Food & Rural Affairs — Great Britain HFC phasedown consultation and May 2026 policy update.
• Environment Agency and Defra — current and future F-gas product restrictions in Great Britain.
• DAERA — fluorinated greenhouse gas regulation in Northern Ireland.
• Regulation (EU) 2024/573 — EU fluorinated greenhouse gas rules.
• Carrier — AquaSnap 61AQ published product information.
• Heat Pumps Watch / NaturalRefrigerants.com — EU heat-pump refrigerant certification data.
• IPCC Sixth Assessment Report — refrigerant global warming potential methodology.