Overview
ISO 8066-2:2001 specifies requirements for rubber and thermoplastic hoses and hose assemblies used to circulate refrigerant R134a (tetrafluoroethane) in automotive air‑conditioning systems. The standard covers design, dimensional limits, classification, and required testing to limit refrigerant loss and system contamination. It applies to hoses and assemblies intended to operate in the range −40 °C to +125 °C and requires that the actual coupling intended for service be used during testing because of the critical hose–coupling interface.
Key Topics and Technical Requirements
- Scope & classification
- Defines grades A–E (rubber textile‑reinforced, rubber wire‑reinforced, thermoplastic barrier/veneer, thermoplastic covered) and Groups 1–4 (discharge/liquid vs suction, moisture resistance levels).
- Dimensions
- Prescribes inside and outside diameter tolerances and allowable wall thickness variation for common nominal bores.
- Leakage & refrigerant loss
- Leakage test: mass loss ≤ 10% of initial refrigerant after conditioning (90 °C) with no visible deterioration.
- Long‑term refrigerant loss limits (based on internal surface area): at 80 °C - Grades A/B: 29.0 kg/m²·year, Grades C/D/E: 9.7 kg/m²·year; at 90 °C - Grades A/B: 40.0, Grades C/D/E: 30.0.
- Mechanical & environmental tests
- Ageing: 168 h at 125 °C on a mandrel, followed by 2.4 MPa hydrostatic test.
- Low‑temperature and ozone resistance tests (normative annexes).
- Vacuum (reduced pressure): 13.3 kPa ± 6 kPa (absolute) for 2 min; outside diameter reduction ≤ 20%.
- Length change under pressure: at 2.4 MPa, contraction ≤ 4% or extension ≤ 2%.
- Bursting pressure: minimum 12 MPa (120 bar) after refrigerant‑loss conditioning.
- Proof pressure: hold at 50% of burst pressure for 2 min ± 30 s with no leakage.
- Chemical compatibility
- Extraction limits for material components by R134a and volume change limits for rubber and thermoplastic linings (ISO 1817 method).
- Testing with service couplings
- Annexes include detailed procedures: refrigerant loss, low‑temperature, extraction, water ingression, coupling integrity, etc.
Applications and Who Uses It
- Automotive OEMs specifying air‑conditioning hose assemblies and connectors
- Hose manufacturers and material suppliers designing R134a service hoses
- Test laboratories and certification bodies performing compliance testing
- Aftermarket parts suppliers and service technicians validating hose replacements
- Regulatory and compliance engineers ensuring refrigerant containment and environmental safety
Related Standards
- ISO 8066‑1 (R12 refrigerant)
- ISO 8330 (vocabulary)
- ISO 1402 (hydrostatic testing)
- ISO 4671 (dimensional measurement)
- ISO 1817 (effect of liquids on rubber)
- SAE J51, SAE J2064 (related refrigerant hose guidance)
Keywords: ISO 8066-2:2001, R134a hose standard, automotive air conditioning hose, refrigerant hose testing, hose assemblies, leak test, burst pressure.