HEAT PUMPS


Refrigerant choice is becoming a design decision


I


As refrigerant regulation tightens, choosing the right refrigerant is becoming an early- stage HVAC design decision rather than a final equipment choice. Peter Wilson, area sales manager at AHU manufacturer IV Produkt, explains how the ThermoCooler HP Multiref concept gives consultants and contractors a choice between R290 and R454C, allowing refrigerant strategy to reflect the building, application, safety requirements and long- term performance


V Produkt’s new version of ThermoCooler HP has been developed to address an important HVAC design decision: which refrigerant is most appropriate for a specific building and application? The integrated reversible heat pump module for our Envistar Flex air handling units is available with either R290 or R454C through IV Produkt’s Multiref concept. This gives consultants and contractors a choice between two refrigerants with a GWP below 150, while retaining the advantages of an AHU with an integrated heat pump system.


Refrigerant selection can no longer be left until the final stages of equipment specification or contractor appointment. It affects building layout, safety measures, servicing, carbon reporting, regulatory compliance and future asset value. Rather than assume that one refrigerant will suit every project, ThermoCooler HP provides different routes for new buildings, major refurbishments and constrained upgrades.


Regulation is changing the design process


While the UK industry continues to debate F-Gas phasedown statements, the wider regulatory direction is clear. From 1 January 2027, the European F-Gas Regulation will introduce tighter GWP limits for new equipment. For AHU- integrated reversible heat pumps below 50 kW, refrigerants must have a GWP below 150. The same level will apply for all capacities, also over 50kW, from 1 January 2030.


This does not mean existing R410A and R32 systems must immediately be removed. They can continue to operate throughout their technical lives and be serviced. However, higher-GWP refrigerants are likely to become more costly as quotas reduce. Buildings using them may also find it harder to achieve the same environmental and BREEAM ratings as those designed around lower-GWP alternatives. HVAC systems installed now may operate for decades, so refrigerant choice must consider more than immediate compliance. Both ThermoCooler HP versions provide a route below the new GWP 150 threshold, allowing the design team to select according to project conditions.


Different buildings require different refrigerant routes


R290 is a natural refrigerant with a GWP of approximately 0.02. It provides high energy and system efficiency and is likely to be preferred for


many new buildings and major refurbishments. However, R290 is classified as an A3 refrigerant. Its flammability places specific requirements on equipment, controls, detection systems, installation and ductwork design. In a new building, these requirements can be addressed from the outset. The design team can allow for separate exhaust ducts, evacuation sections, plant space and necessary safety measures. ThermoCooler HP with R290 combines the environmental and efficiency benefits of R290 with an AHU- integrated heating and cooling solution. The same approach will not be practical in every existing building. Many refurbishment projects in existing buildings might have fixed duct routes, restricted plant space and limited scope for alterations. In these situations, R290 may add extra costs or technical complexity that the project cannot accommodate. For these applications, ThermoCooler HP with R454C provides an alternative route. With a GWP of 146, R454C offers a lower-GWP, regulation-compliant option for projects where existing building conditions make the use of R290 more challenging. The Multiref concept does not suggest


the refrigerants are identical. Their safety classifications and design requirements differ. Its purpose is to enable a project-specific decision without losing the benefits of the AHU-integrated ThermoCooler HP platform.


The whole system must be considered


Refrigerant GWP is important, but it should not be considered in isolation. A traditional comfort- cooling system with low-GWP refrigerants, may still require separate chillers, dry-coolers, pumps, pipework, controls and associated equipment. Each component adds material, installation work and embodied carbon. ThermoCooler HP integrates the reversible heat pump into the air handling unit. In suitable applications, this can reduce equipment requirements and lower embodied carbon by more than 50% compared with a conventional separate-system arrangement. A low-GWP refrigerant does not necessarily


produce the lowest total environmental impact if the overall solution requires substantially more equipment and materials. Operational efficiency, embodied carbon, maintenance and system complexity must all form part of the assessment.


By offering R290 and R454C within the same AHU-integrated concept, ThermoCooler HP allows designers to consider both refrigerant and whole-system impact.


Refrigerant strategy and asset value Tenants increasingly set environmental and


30 BUILDING SERVICES & ENVIRONMENTAL ENGINEER SEPTEMBER 2026


sustainability requirements for the buildings they occupy. They expect efficient comfort cooling, credible carbon data and confidence that systems will remain practical to operate and maintain.


A building with high energy costs, poor


environmental ratings or significant replacement requirements can be harder to lease, finance or sell. Reliance on a higher-GWP refrigerant could also increase servicing costs and bring forward major reinvestment. Specifying ThermoCooler HP with either R290 or R454C enables the designer to meet project needs, while still selecting a refrigerant below the forthcoming GWP limit. The Multiref concept can also preserve


future options. The ThermoCooler HP DX-circuit module is designed for compatibility with both refrigerants. Detection, control and safety functions vary between versions, but the main DX-platform remains the same. Where the unit and duct system are designed proactively, an R454C installation may be prepared for a later conversion to R290. Some safety and control functions would need adaptation, but the common AHU platform makes a conversion practical and feasible, rather than replacing the complete unit. This may especially benefit refurbishments where R290 cannot be accommodated immediately, but could become viable after building changes.


A practical response to a changing market


IV Produkt sees R290 and natural refrigerants as a strong long-term direction. R290 is also being used in the company’s new manufacturing and office facilities. However, millions of existing UK and


European buildings require energy-efficiency improvements and decarbonisation measures, and not all can accommodate R290. Removing other compliant options could make some projects technically difficult or financially unviable, slowing improvements to buildings that need to reduce energy use and carbon emissions. ThermoCooler HP and the Multiref concept have been developed in response to that challenge. For projects that can accommodate an A3 refrigerant, the R290 version provides very low GWP and high efficiency. Where building constraints make that route impractical, the R454C version provides a compliant alternative below GWP 150. The key is to make refrigerant choice early and as part of the wider building design strategy. ThermoCooler HP gives consultants and contractors the flexibility to make that decision according to the application, while maintaining the operational, material and embodied- carbon advantages of an integrated reversible heat pump module for AHUs.


Read the latest at: www.bsee.co.uk


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42