ACEA Oil Sequences vs. Automotive A/C Refrigerants
Comparing 2 standards across 14 specifications. 14 key differences identified.
The European Automobile Manufacturers’ Association (ACEA) Oil Sequences establish stringent oil performance specifications tailored to European driving conditions and exhaust aftertreatment devices. Dividing into A/B Sequences (High-SAPS for older passenger cars without particulate filters) and C Sequences (C2, C3, C5, C6 Low/Mid-SAPS for DPF diesel and GPF gasoline particulate filters).
Automotive air conditioning refrigerants are standardized under SAE J639, SAE J2842, and EPA regulations into R-12 (CFC-12 legacy), R-134a (HFC-134a standard since 1994), and R-1234yf (HFO ultra-low GWP standard on modern vehicles), each featuring unique quick-connect service port dimensions and dedicated synthetic compressor oils (PAG vs POE).
Specification Comparison Table
14 Parameters| Parameter / Spec | ||
|---|---|---|
|
Standardization
|
ACEA Oil Sequences (A/B for standard engines, C for catalyst-compatible, E for heavy-duty commercial diesel) | — |
|
SAPS Definition
|
Sulfated Ash, Phosphorus, and Sulfur additives (ZDP anti-wear agents and metallic detergents) | — |
|
ACEA A3/B4 (High SAPS)
|
High performance/stay-in-grade stable oil for high-revving European engines; HTHS ≥ 3.5 mPa·s (BMW LL-01, MB 229.5, VW 502.00) | — |
|
ACEA A5/B5 (High SAPS, Low Friction)
|
Low-viscosity fuel economy oil with HTHS 2.9 to 3.5 mPa·s (Ford WSS-M2C913-D, Volvo) | — |
|
ACEA C3 (Mid SAPS, High HTHS)
|
The European DPF/GPF gold standard: HTHS ≥ 3.5 mPa·s, Sulfated Ash ≤ 0.8% (BMW LL-04, MB 229.51/229.52, VW 504.00/507.00, Porsche C30) | — |
|
ACEA C5 & C6 (Low SAPS, Low HTHS)
|
Ultra-low viscosity (0W-20) for modern fuel economy: HTHS 2.6 to 2.9 mPa·s with LSPI protection (BMW LL-17 FE+, VW 508.00/509.00) | — |
|
Governing Standards
|
— | SAE J639 / SAE J2842 / ASHRAE 34 (Refrigerant Safety) / EPA SNAP Program |
|
R-12 (Dichlorodifluoromethane)
|
— | Global Warming Potential (GWP): 10,900 | Ozone Depletion Potential (ODP): 1.0 | 7/16" threaded flare ports | Mineral oil |
|
R-134a (1,1,1,2-Tetrafluoroethane)
|
— | GWP: 1,430 | ODP: 0.0 | High-side 16 mm / Low-side 13 mm quick-connect ports | PAG 46/100/150 oil |
|
R-1234yf (2,3,3,3-Tetrafluoropropene)
|
— | GWP: < 1.0 | ODP: 0.0 | High-side 17 mm / Low-side 14 mm left-hand keyed ports | PAG/POE specialized oils |
|
R-744 (Carbon Dioxide / CO2)
|
— | GWP: 1.0 | Transcritical system operating at ultra-high pressures up to 130 bar (1,885 psi) | Mercedes S-Class option |
|
Standard Low-Side Operating Pressure
|
— | 25 to 45 psi (1.7 to 3.1 bar) at 21°C–32°C (70°F–90°F) ambient |
|
Standard High-Side Operating Pressure
|
— | 150 to 250 psi (10.3 to 17.2 bar) depending on ambient condenser airflow |
|
Oil Compatibility Rule
|
— | Never use mineral oil with R-134a/R-1234yf; PAG oil is strictly hygroscopic (absorbs atmospheric moisture rapidly) |