Types of Refrigerants
Refrigeration is a silent workhorse of modern life. From the freezer that stores your Sunday roast to the massive chillers that keep supermarkets stocked with fresh produce, the technology relies on a family of chemicals known as refrigerants. Over the past decades, the UK has witnessed a dramatic shift in the types of refrigerants in use, driven by environmental concerns, legislative pressure, and rapid advances in heat‑transfer science.
For manufacturers, installers, facility managers, and building owners, understanding this evolving landscape is no longer optional—it is a prerequisite for compliance, cost‑effectiveness, and corporate responsibility. This article unpacks the main refrigerant categories that dominate the UK market, explores how they are applied in domestic versus commercial settings, and explains how the UK’s REF‑Com (Refrigerant Compliance) framework steers the industry toward a lower‑GWP future.
1. Refrigerant Families – An Overview
| Family | Typical Global Warming Potential (GWP) | Key Characteristics | Common UK Applications |
|---|---|---|---|
| CFCs (Chlorofluorocarbons) | > 10,000 | Highly stable, excellent thermodynamic properties, but ozone‑depleting. | Phased‑out; only legacy equipment (e.g., very old air‑conditioners) still contains R12. |
| HCFCs (Hydrochlorofluorocarbons) | 1,500–2,000 | Moderate ozone depletion, lower GWP than CFCs, still being withdrawn. | R22 was once the workhorse for residential split‑systems; now largely replaced. |
| HFCs (Hydrofluorocarbons) | 100–12,000 (depending on blend) | No ozone depletion; widely used but GWP can be high. | R410A, R404A, R507, R134a dominate domestic heat‑pump and commercial refrigeration markets. |
| HFOs (Hydrofluoro‑olefins) | < 10 | Very low GWP, mild flammability, good thermodynamic performance. | R1234yf (automotive AC), R1234ze(E) (heat pumps), emerging commercial chillers. |
| Natural Refrigerants – CO₂ (R744), Ammonia (R717), Hydrocarbons (R290, R600a, R601a) | CO₂: 1, R717: 0, Hydrocarbons: 3–4 | Zero‑ozone‑depletion, ultra‑low GWP; often flammable or toxic, requiring specialised designs. | CO₂ transcritical chillers in supermarkets; ammonia in large‑scale industrial refrigeration; hydrocarbons in domestic fridges and small‑capacity commercial units. |
| Low‑GWP Blends (e.g., R452A, R448A, R449A) | 1,200–2,000 | Engineered to mimic the performance of high‑GWP HFCs while reducing climate impact. | Retro‑fit solutions for existing equipment, especially in commercial refrigeration. |
Key takeaway: The UK market is moving decisively away from CFCs and HCFCs, embracing low‑GWP HFCs, HFOs, and natural refrigerants. The choice of refrigerant is now dictated not just by thermodynamic efficiency but also by the legal limits on GWP and the operational safety profile required for each installation.
2. Domestic Refrigeration – What You’ll Find in a Typical UK Home
2.1. Residential Air‑Source Heat Pumps
- Current dominant refrigerant: R410A (GWP ≈ 2,090) and, increasingly, R32 (GWP ≈ 675).
- Why the shift: R32 offers higher energy efficiency and a lower GWP, aligning with the UK’s Phase‑down targets.
- ACL London’s role: We audit existing heat‑pump systems, advise on retrofits to R32 or HFO‑based models, and support the paperwork required under REF‑Com for refrigerant change‑over.
2.2. Domestic Refrigerators & Freezers
- Typical refrigerants: R600a (isobutane, GWP ≈ 3) for most freestanding fridges; R134a (GWP ≈ 1,300) for some integrated freezer units.
- Regulatory context: Since 2019, the UK has mandated the use of low‑GWP refrigerants (≤ 5) for new domestic appliances, effectively making R600a the default choice.
- Practical note: R600a is mildly flammable (A3 classification). Modern appliances mitigate risk through sealed systems and low charge limits (< 150 g).
2.3. Emerging Technologies – “Smart” Heat‑Pump Water Heaters
- Refrigerants in development: R1234ze(E) (GWP ≈ 6) and low‑charge CO₂ (R744) trans critical cycles.
- Market outlook: With the UK’s net‑zero target, water‑heating heat pumps are set to proliferate. ACL London’s engineering team is already testing prototype installations that meet both energy‑performance (SAP) and REF‑Com compliance criteria.
3. Commercial Refrigeration – From Supermarkets to Industrial Chill‑ers
3.1. Supermarket Refrigeration
| System Type | Typical Refrigerant | Why It’s Used |
|---|---|---|
| Display cases & walk‑in coolers | R290 (propane, GWP ≈ 3) or R448A (GWP ≈ 1,200). | R290 offers excellent thermodynamic performance for low‑temperature applications, while R448A provides a non‑flammable alternative for larger charge volumes. |
| Transcritical CO₂ chillers | R744 (GWP = 1) | High‑efficiency at low ambient temperatures; increasingly mandatory for new builds as CO₂ meets the UK’s Phase‑down goals. |
- Regulation impact: The REF‑Com Phase‑down schedule requires supermarkets to reduce HFC usage by 80 % by 2030. Many major UK retailers have already adopted CO₂ systems, benefitting from lower operating costs and carbon‑credit incentives.
3.2. Food‑Service & Hospitality
- Typical refrigerants: R290 for small‑capacity under‑counter units; R452A for medium‑capacity walk‑in freezers.
- Safety measures: ACL London provides on‑site training for staff on handling flammable refrigerants, fulfilling the REF‑Com “Competency” requirement (Section 6 of the F‑Gas Regulations).
3.3. Industrial Cooling & Process Refrigeration
- Common refrigerants: Ammonia (R717) for large‑scale, high‑capacity systems; CO₂ (R744) for cascade or transcritical configurations; HFO blends for medium‑size loops.
- Why ammonia still reigns: Zero GWP, high latent heat of vaporisation, and excellent energy‑efficiency, albeit with toxicity concerns that are mitigated through robust leak‑detection and emergency‑shutdown systems.
3.4. Data‑Center & Server‑Room Cooling
- Emerging refrigerants: R1234yf (GWP ≈ 4) and low‑charge CO₂.
- Trend: The “green‑IT” movement pushes data‑centres to adopt refrigerants that minimise climate impact while delivering precise temperature control. ACL London partners with IT‑facility managers to design modular CO₂ cooling loops that integrate seamlessly with existing UPS and HVAC infrastructure.
4. The UK REF‑Com (Refrigerant Compliance) Framework
4.1. What Is REF‑Com?
REF‑Com (Refrigerant Compliance) is the UK’s umbrella scheme that translates the EU F‑Gas Regulation (Regulation (EU) No 517/2014) into domestic law, overseen by the Environment Agency (EA) and enforced by HSE. Its core aims are to:
- Phase‑down the total stock of high‑GWP fluorinated gases.
- Control the sale, import, and use of refrigerants via licensing.
- Ensure proper training, record‑keeping, and leak‑detection.
The scheme is divided into three primary sections:
| Section | Scope | Key Obligations |
|---|---|---|
| Section 6 | Small‑capacity appliances (≤ 5 kg refrigerant charge). | No licensing required, but manufacturers must certify compliance; end‑users must keep a product register. |
| Section 7 | Larger commercial/industrial equipment (> 5 kg). | Requires a refrigerant handling licence, annual leak‑testing reports, and equipment registration with the EA. |
| Section 8 – Fluorinated Gas Reporting | All entities that manufacture, import, or place on the market refrigerants. | Annual submission of F‑Gas data to the EA; penalties for omissions. |
4.2. Phase‑Down Targets
| Year | Maximum Allowed Stock of HFCs (in tonnes CO₂‑eq.) |
|---|---|
| 2020 | 100 % (baseline) |
| 2023 | 68 % |
| 2026 | 44 % |
| 2030 | 18 % |
| 2035 | 5 % |
These targets are cumulative across the UK and are enforced through the REF‑Com licence system. Failure to meet the limits can result in substantial fines (£5,000–£50,000 per breach) and revocation of licences.
4.3. Competency & Training
The REF‑Com regime mandates that any person handling refrigerants above 5 kg must hold a qualifying certificate (e.g., the City & Guilds Level 2/3 “F‑Gas Handling” qualification). For flammable natural refrigerants, an additional ATEX‑compatible safety course is required.
ACL London’s advantage: We maintain an in‑house training academy accredited by the EA. Our courses are tailored to the specific refrigerant mix of a client’s portfolio, ensuring that all technicians meet the competency standards without the need for external providers.
4.4. Record‑Keeping & Leak‑Detection
- Equipment Register: Must be kept up‑to‑date for every system > 5 kg, including make, model, refrigerant type, charge amount, and location.
- Leak‑Detection Frequency:
- Annual for systems > 50 kg refrigerant charge.
- Every 2 years for systems between 5–50 kg.
- Acceptable Leak‑Rate: 5 % of the total charge per annum for most equipment; 10 % for mobile plant.
Non‑compliance can trigger an environmental health notice (EHSN), compelling immediate remedial actions and possible shutdowns.
5. Choosing the Right Refrigerant – A Practical Decision‑Tree
- Determine the Application Size & Temperature Range
- Low‑temperature (< ‑20 °C) – Consider CO₂ (transcritical) for large chillers, or R448A for medium‑size walk‑ins.
- Medium‑temperature (0 °C to +10 °C) – R290 or R32 (if non‑flammable equipment is required).
- Assess Safety Constraints
- Flammability: If the installation environment cannot accommodate A3 refrigerants, opt for low‑GWP HFO blends (e.g., R1234ze).
- Toxicity: For high‑capacity industrial plants, ammonia remains the gold standard, provided robust detection & ventilation are in place.
- Check Regulatory Limits
- Charge Size > 5 kg: Licencing and leak‑testing obligations apply.
- Phase‑down Target: Choose a refrigerant that will not exceed your projected GWP inventory for the next 5–10 years.
- Calculate Lifecycle Cost
- Energy Efficiency (COP) – Higher COP translates to lower electricity bills, which can offset higher upfront costs of low‑GWP equipment.
- Maintenance & Training: Flammable natural refrigerants may require additional training, but the overall cost of compliance is often lower than that of high‑GWP HFC replacements.
ACL London’s Refrigerant Optimisation Service runs a full cost‑benefit analysis, delivering a recommendation that balances performance, safety, and REF‑Com compliance.
6. Future Outlook – What’s Next for UK Refrigeration?
- Accelerated CO₂ Adoption – Government incentives (e.g., the Carbon Reduction Commitment (CRC)) are making CO₂ the default for large‑scale refrigeration. Expect a 30 % increase in new CO₂ installations by 2027.
- HFO‑Dominated Heat‑Pump Market – By 2030, more than half of residential heat‑pump sales are projected to use R32 or R1234ze(E), driven by the building‑regulation Part L amendments that favour low‑GWP solutions.
- Digital Leak‑Detection – IoT‑enabled sensors will provide continuous real‑time monitoring, simplifying the REF‑Com reporting burden. ACL London is piloting a cloud‑based platform that automatically uploads leak‑test data to the EA portal.
- Regulatory Tightening – The UK is expected to introduce a “GWP‑cap” on new equipment in 2025, limiting the maximum GWP of any refrigerant used to ≤ 150. Early adopters will gain a competitive edge.
7. How ACL London Can Help You Navigate the Refrigerant Transition
| Service | What You Get | Why It Matters |
|---|---|---|
| Regulatory Audits | Comprehensive gap analysis against REF‑Com Sections 6–8. | Avoid costly fines and licence suspensions. |
| System Design & Retro‑Fit | Custom engineering solutions using low‑GWP refrigerants (CO₂, HFOs, hydrocarbons). | Future‑proof your assets and improve energy efficiency. |
| Training & Competency | EA‑accredited courses for technicians, plus ATEX safety modules for natural refrigerants. | Meet legal competency requirements and boost staff confidence. |
| Leak‑Detection & Monitoring | Installation of smart sensors, annual testing schedules, and automated reporting. | Simplify compliance and reduce greenhouse‑gas emissions. |
| Lifecycle Cost Modelling | Detailed ROI calculations, including energy savings, refrigerant charge reductions, and carbon‑credit benefits. | Make informed investment decisions. |
Contact us today to schedule a free preliminary consultation. Let ACL London be your trusted partner as the UK moves toward a climate‑neutral refrigeration future.
Closing Thoughts
The UK’s refrigerant market is undergoing a profound transformation. From the humble domestic freezer to the sprawling supermarket chill‑room, the choice of refrigerant now intertwines thermodynamic performance, safety, and strict regulatory compliance. Understanding the different refrigerant families, their appropriate applications, and the obligations under the REF‑Com framework is essential for anyone involved in design, installation, or operation of cooling systems.
By staying ahead of the phase‑down schedule, investing in low‑GWP technologies, and partnering with a specialist like ACL London, businesses can not only avoid penalties but also reap tangible benefits: lower operating costs, enhanced brand reputation, and a clear contribution toward the UK’s net‑zero ambition.
