ISO 20766-7:2023

Overview

ISO 20766-7:2023 - "Road vehicles - Liquefied petroleum gas (LPG) fuel system components - Part 7: Remotely controlled service valve with excess flow valve" specifies definitions, design principles, marking and testing requirements for remotely controlled service valves that incorporate an excess flow valve. It applies to LPG fuel system components used on motor vehicles (mono-fuel, bi-fuel or dual-fuel) as defined in ISO 3833 and for gaseous fuels in accordance with ISO 9162. The standard covers devices with nominal service pressures in the range of 110 kPa to 840 kPa (adjustable by ratio for other pressures).

Key topics and technical requirements

• Scope and exclusions: Applicable to vehicle-mounted remotely controlled service valves with excess flow valves; not applicable to fuel containers, stationary gas engines, container mounting hardware, electronic fuel management or refuelling receptacles.
• Marking requirements: Manufacturer name/trademark, model/part number, working pressure and temperature range, manufacture date (year/month), rated closing flow capacity; recommended markings include flow direction, type of fuel, electrical ratings and ISO 20766-7 reference. Special marks (H1/H2/H3) indicate start/stop compatibility.
• Construction & safety:
  • Valve must withstand maximum operating pressure and specified temperature range (per ISO 20766‑1).
  • Electrically operated valves must be isolated from LPG-containing parts; isolation resistance > 10 MΩ.
  • Valve must default to closed when power is removed and automatically close when the engine is not running (with limited exceptions for recirculation and commanded stops).
  • Excess flow valve must be mounted inside the container and include a bypass for pressure equalization (unless reset provided).
• Performance limits:
  • Excess flow valve cutoff at a differential pressure of 90 kPa, with cut-off flow ≤ 8 000 cm³/min (system designers may specify different maxima for large engines).
  • Bypass flow ≤ 500 cm³/min at 700 kPa differential when in cut-off.
• Testing:
  • Hydrostatic strength (2.25 × working pressure), high/low temperature leakage (≤15 cm³/h at 150% WP after conditioning), seat leakage, endurance (continued operation) and operational tests per ISO 20766‑2. Degree of protection for in-container electrical connections referenced to IEC 60529 (IP40).

Applications and who uses this standard

• Automotive OEMs and component manufacturers designing LPG service valves and multivalve assemblies.
• Certification bodies and independent test laboratories performing compliance and type-approval testing.
• Regulatory authorities and vehicle converters ensuring safety and conformity for LPG-powered road vehicles.
• Aftermarket suppliers and systems integrators implementing start/stop compatible LPG components.

Related standards

• ISO 20766‑1:2018 - General requirements and definitions
• ISO 20766‑2 - Performance and test methods (referenced test procedures)
• ISO 3833 - Vehicle classification
• ISO 9162 - Gaseous fuel system requirements
• IEC 60529 - Degrees of protection (IP Code)

Keywords: ISO 20766-7:2023, LPG service valve, remotely controlled service valve, excess flow valve, automotive LPG components, hydrostatic strength, seat leakage, endurance test, ISO 20766 series.