R513A (trade name: Opteon™ XP10) is a near-azeotropic HFC/HFO refrigerant blend composed of 56% R-1234yf and 44% R-134a. With a Global Warming Potential (GWP) of 631 — a 56% reduction from R-134a’s 1,430 — it is the primary low-GWP replacement for R-134a in centrifugal chillers, direct expansion chillers, and medium-to-high temperature commercial refrigeration systems.
R513A is classified as an A1 refrigerant (non-toxic, non-flammable) under ASHRAE Standard 34 — the same safety class as R-134a. It behaves as a near-azeotrope with effectively zero temperature glide, making it straightforward to service and commission. Unlike some HFO blends, R513A must be charged in the liquid phase to maintain blend composition.
This page provides the complete R513A pressure-temperature (PT) chart, physical properties, a comparison with R-134a, charging and service guidance, and Geson chiller configurations available with R513A.
R513A Pressure Temperature Chart (PT Chart)
R513A is a near-azeotropic blend with effectively zero temperature glide, so a single pressure column is sufficient for service purposes. Pressures below are vapor pressure in PSIG at saturation temperatures from −40°F to 150°F.
Typical operating range for centrifugal chillers: Evaporating temperature 35–42°F (suction pressure ~27–34 psig); condensing temperature 95–105°F (discharge pressure ~153–183 psig).
| Temp (°F) | Temp (°C) | Pressure (PSIG) |
|---|---|---|
| −40 | −40.0 | 9.8 |
| −35 | −37.2 | 12.3 |
| −30 | −34.4 | 15.2 |
| −25 | −31.7 | 18.5 |
| −20 | −28.9 | 22.3 |
| −15 | −26.1 | 26.6 |
| −10 | −23.3 | 31.4 |
| −5 | −20.6 | 36.9 |
| 0 | −17.8 | 43.0 |
| 5 | −15.0 | 49.8 |
| 10 | −12.2 | 57.4 |
| 15 | −9.4 | 65.8 |
| 20 | −6.7 | 75.1 |
| 25 | −3.9 | 85.3 |
| 30 | −1.1 | 96.6 |
| 35 | 1.7 | 109.0 |
| 40 | 4.4 | 122.6 |
| 45 | 7.2 | 137.4 |
| 50 | 10.0 | 153.7 |
| 55 | 12.8 | 171.4 |
| 60 | 15.6 | 190.6 |
| 65 | 18.3 | 211.5 |
| 70 | 21.1 | 234.1 |
| 75 | 23.9 | 258.5 |
| 80 | 26.7 | 285.0 |
| 85 | 29.4 | 313.5 |
| 90 | 32.2 | 344.1 |
| 95 | 35.0 | 377.1 |
| 100 | 37.8 | 412.4 |
| 105 | 40.6 | 450.3 |
| 110 | 43.3 | 490.8 |
| 120 | 48.9 | 578.8 |
| 130 | 54.4 | 677.2 |
| 140 | 60.0 | 787.3 |
| 150 | 65.6 | 910.0 |
Service note: R513A pressures are very close to R-134a across the operating range. When transitioning from R-134a to R513A, existing pressure gauges calibrated for R-134a can be used — verify with your gauge manufacturer. R513A must always be charged in the liquid phase. Charging from the vapour phase causes fractionation and incorrect blend composition in the system.
R513A Physical Properties
| Property | R513A Value |
|---|---|
| Chemical classification | HFC/HFO Near-Azeotropic Blend |
| Components | R-1234yf (56%) + R-134a (44%) |
| Trade name | Opteon™ XP10 (Chemours) |
| Molecular weight | 108.4 g/mol |
| Boiling point (1 atm) | −29.4°F (−34.1°C) |
| Critical temperature | 186.6°F (85.9°C) |
| Critical pressure | 573.3 psia |
| Global Warming Potential (GWP) | 631 (vs R-134a: 1,430) |
| Ozone Depletion Potential (ODP) | 0 |
| ASHRAE 34 safety class | A1 (non-toxic, non-flammable) |
| Temperature glide | Near-zero (azeotropic behaviour) |
| Lubricant compatibility | POE (Polyolester) oil required |
| Charging method | Liquid phase only |
| Refrigerant cylinder colour (AHRI) | Coral/salmon |
R513A vs R-134a: Side-by-Side Comparison
R513A was specifically designed to replace R-134a in medium-to-high temperature applications — particularly centrifugal chillers — while maintaining the same A1 non-flammable safety classification and near-identical operating pressures and capacity.
| Parameter | R513A | R-134a |
|---|---|---|
| GWP | 631 | 1,430 |
| ODP | 0 | 0 |
| ASHRAE safety class | A1 | A1 |
| Operating pressure (40°F) | ~122.6 psig | ~118.8 psig |
| Cooling capacity (relative) | 95–100% of R-134a | Baseline |
| Energy efficiency (COP) | Equal or slightly better | Baseline |
| Temperature glide | Near-zero | Zero (single component) |
| Drop-in replacement? | Near drop-in — oil flush required | — |
| Charging method | Liquid phase only | Liquid or vapour |
| Lubricant | POE oil | POE oil (same) |
| EU F-Gas regulation | Permitted in new equipment (GWP <750) | Banned in new equipment from 2022 |
| Primary applications | Centrifugal chillers, DX chillers, commercial refrigeration | Centrifugal chillers, automotive AC, commercial refrigeration |
Key advantage of R513A over R-134a: R-134a has been banned in new mobile air conditioning systems in the EU since 2011, and in new stationary refrigeration equipment with GWP >150 since 2022. R513A’s GWP of 631 keeps it compliant for new equipment under current EU F-Gas regulations. For centrifugal chiller retrofits, R513A is the most straightforward R-134a replacement — near-identical pressures, same POE oil compatibility, A1 safety class maintained.
R513A Applications
R513A is primarily used in medium-to-high temperature refrigeration and chiller applications where R-134a has historically been the refrigerant of choice:
- Centrifugal chillers (HVAC): The primary application for R513A. Large-capacity centrifugal chillers for commercial buildings, hospitals, data centres, and district cooling plants. R513A’s near-identical pressure profile to R-134a makes it the preferred retrofit and new-build refrigerant for centrifugal compressor systems. Carrier, Trane, and other major manufacturers offer centrifugal chillers with R513A factory configuration.
- Direct expansion (DX) water chillers: Scroll and screw chillers used in commercial and industrial applications in the 10–200TR range, where the operating temperature range suits R513A’s properties.
- Medium temperature commercial refrigeration: Supermarket display cases, walk-in coolers, and medium-temperature industrial refrigeration systems.
- Hybrid cascade systems: R513A can be used as the high-temperature stage refrigerant in cascade systems for low-temperature applications.
- Ice rink systems: Direct expansion ice rink floor refrigeration systems where R-134a has previously been used.
Not suitable for: Low-temperature applications requiring evaporating temperatures below −20°C. For these applications, R448A, R449A, or R452A are more appropriate choices.
R513A Charging and Service Guidance
Critical: Always Charge in the Liquid Phase
Unlike R-134a, which can be charged as either liquid or vapour, R513A must always be charged in the liquid phase. Charging as vapour causes fractionation — the two components (R-1234yf and R-134a) enter the system at different rates, resulting in incorrect blend composition, reduced capacity, and off-spec operating pressures. Use the liquid valve on the refrigerant cylinder and a liquid charging manifold or charge into the liquid line.
Oil Requirements
R513A requires Polyolester (POE) oil — the same lubricant used with R-134a. For retrofits from R-134a systems already using POE oil, a complete oil flush is still recommended to remove any contamination, but the oil type does not change. For retrofits from older systems using mineral oil, a complete oil flush and replacement with POE oil is mandatory before charging with R513A.
Retrofit from R-134a
R513A is considered a near drop-in replacement for R-134a. Retrofit procedure:
- Recover existing R-134a charge using certified recovery equipment.
- Replace the filter drier with a new drier rated for HFO refrigerants.
- If the system used mineral oil: flush with POE oil and replace. If already on POE oil: check condition and replace if degraded.
- Pressure test and evacuate the system to minimum 200 microns.
- Charge with R513A in the liquid phase to the manufacturer’s specified weight — do not use R-134a charge weights directly as R513A has slightly different density.
- Monitor operating pressures against the R513A PT chart for the first 30 minutes and compare to the system’s design operating conditions.
Leak Detection
Use a refrigerant leak detector rated for HFO refrigerants. R513A contains R-1234yf, which some older leak detectors may not detect reliably. Verify your leak detector is rated for HFO/HFC blends before use.
Geson Chillers Compatible with R513A
Geson water-cooled and air-cooled chiller configurations are available with R513A for applications requiring a low-GWP A1 refrigerant with near-identical performance to R-134a:
- Water-cooled scroll chillers — 10TR to 100TR: Available with R513A factory configuration for commercial HVAC and process cooling applications. POE oil filled from factory.
- Water-cooled screw chillers — 50TR to 1,500TR: R513A available on request for large commercial and industrial installations. Specify at order stage.
- Air-cooled scroll chillers — 10TR to 100TR: R513A configuration available for direct expansion process cooling and commercial refrigeration.
All Geson R513A chiller configurations ship with factory charge documentation, refrigerant charge weight recorded on the nameplate, and pre-delivery pressure test records. Lead time: 15 working days standard.
Request a quotation → Provide your cooling load (TR or kW), application, and operating temperature range. Geson engineering will respond within 24 hours.
Frequently Asked Questions about R513A
What is R513A refrigerant?
R513A is a near-azeotropic HFC/HFO refrigerant blend made from 56% R-1234yf and 31.1% R-134a. It has a GWP of 631 — 56% lower than R-134a’s 1,430 — and an ASHRAE A1 (non-flammable, non-toxic) safety rating. It is designed as the primary low-GWP replacement for R-134a in centrifugal chillers, DX water chillers, and medium-to-high temperature commercial refrigeration systems.
What is R513A used for?
R513A is primarily used in centrifugal chillers for large commercial buildings, hospitals, data centres, and district cooling plants. It is also used in direct expansion water chillers (10–200TR), medium-temperature commercial refrigeration, and ice rink floor refrigeration systems — all applications where R-134a has historically been the refrigerant of choice.
Is R513A a drop-in replacement for R-134a?
R513A is considered a near drop-in replacement for R-134a. Operating pressures are nearly identical, the A1 safety classification is maintained, and the same POE oil is used. However, a complete oil flush and filter drier replacement are required, and R513A must be charged in the liquid phase only (unlike R-134a, which can be charged as liquid or vapour). It is not a true “no-change” drop-in, but is the closest available replacement for R-134a.
What is the GWP of R513A?
R513A has a Global Warming Potential (GWP) of 631, calculated over a 100-year period relative to CO₂. This is 56% lower than R-134a (GWP 1,430) and allows R513A to comply with EU F-Gas regulations for new equipment (GWP <750 threshold) where R-134a is no longer permitted.
Why must R513A be charged in the liquid phase?
Although R513A behaves as a near-azeotrope, it is technically a blend of two components (R-1234yf and R-134a) with slightly different properties. Charging as vapour causes the lighter component to enter the system preferentially, resulting in incorrect blend composition in the cylinder and the system. Charging in the liquid phase ensures the correct 56/44 composition is maintained throughout the charge. Always use the liquid valve on the cylinder and charge into the liquid line or use a liquid charging adapter.
What oil does R513A use?
R513A requires Polyolester (POE) oil, the same lubricant used with R-134a. Typical viscosity grades are ISO 32 or ISO 46 for scroll and screw compressors — confirm with the compressor manufacturer’s specification. Never use mineral oil or alkylbenzene oil with R513A.
What is the trade name for R513A?
R513A is sold by Chemours under the trade name Opteon™ XP10. This is the same refrigerant blend — 56% R-1234yf and 44% R-134a.
How does R513A compare to R454B?
R513A and R454B are both low-GWP replacements for different refrigerants and are not interchangeable. R513A (GWP 631, A1) replaces R-134a in centrifugal chillers and medium-temperature applications. R454B (GWP 466, A2L) replaces R-410A in residential and light commercial air conditioning systems and scroll/screw process chillers. They have different compositions, different pressure profiles, and different safety classifications. Do not mix these refrigerants or use them interchangeably.
Does Geson manufacture chillers with R513A?
Yes. Geson offers water-cooled scroll chillers (10–100TR), water-cooled screw chillers (50–1,500TR), and air-cooled scroll chillers (10–100TR) with R513A factory configuration. All units ship with factory charge documentation and pre-delivery pressure test records. Contact Geson engineering with your cooling requirements for a formal quotation within 24 hours.
Related Resources
- R454B Refrigerant: PT Chart, Properties & R410A Guide
- Common Types of Chiller Refrigerant: Complete Guide
- Water-Cooled Screw Chillers — 50TR to 1,500TR
- Water-Cooled Scroll Chillers — 10TR to 100TR
- Contact Geson Engineering Team