Fuel control equipment shall comply with the requirements specified in paragraph 9.90.2 to 9.90.6. Any alterations made to the original equipment shall not adversely affect the performance of the equipment, the safety of the installation or the exhaust emission levels.

The LPG fuel control equipment shall incorporate all equipment necessary to convert LPG at high pressure at the fuel service line to the gas-air mixture supplied to the engine, and shall comprise the following components—

• (a)An internal fuel filter, arranged to protect the automatic fuel shut-off device;
• (b)An automatic fuel shut-off device (lock off);
• (c)A vaporiser;
• (d)A pressure regulator;
• (e)A fuel selector, where a dual-fuel system is employed; and
• (f)A gas-air mixer.

• 9.90.3.1Performance

  A vaporiser and pressure regulator assembly shall incorporate a safety device that prevents the passage of vapour after the engine has stopped running, irrespective of whether the ignition is on or off.

• 9.90.3.2Installation

  The vaporiser and pressure regulator assembly shall be securely mounted and installed in accordance with the following—

  • (a)It is accessible for routine maintenance, adjustment, and inspection;
  • (b)It is mounted adjacent to or near the engine inlet;
  • (c)It is protected from impact in the event of a collision;
  • (d)It is either connected directly to, or adjacent to, the automatic fuel shut-off device;
  • (e)The length of any vapour pipe between the converter and the engine shall be minimized, and in no case shall be more than 500mm; and
  • (f)It allows sufficient free movement of fuel and water hoses.
• 9.90.3.3Marking

  Each vaporiser shall be legibly and permanently marked with the following information—

  • (a)The manufacturer’s name and trademark;
  • (b)A definitive model, make, or series identification; and
  • (c)The serial number, month and year of manufacture.

The water circulation system shall be connected such that no flow-control valve in the system (eg thermostat or heater control) is capable of shutting off the flow of hot water.

• 9.90.5.1The gas-air mixer shall be mounted securely and, when fitted remotely, shall be capable of supporting its own weight and any forces applied under normal conditions of operation.
• 9.90.5.2Air filter elements shall not be fitted downstream of the gas-air mixer.

• 9.90.6.1General

  The cross-sectional area (determined by current flow) and the insulation (determined by temperature) of wiring cable shall comply with appropriate national and international standards. The conductors in the wiring cable shall be tinned.

• 9.90.6.2Securing of wiring cable

  All wiring shall be taped, clipped or contained in a loom along its length.

• 9.90.6.3Connectors and terminals

  Connectors and terminals shall have soldered joints and shall be insulated to prevent accidental earthing during operation or routine servicing.