The dangers of LPG
Firstly it is corrosive and it is a “seeking” gas, which means that it is always looking for the easiest way out of its container, be that a cylinder or pipework, or appliance, and it will take advantage of any weakness in the system.
For this reason no soldered joints are allowed, unless they are “Hard Soldered” which is beyond the scope of all but the commercial engineers as it has to be done at 415°C.
So, for practical use, only compression fittings using Soft Copper Olives or “Cutting Rings” can be used on the fixed pipework and the complete system must be leak and pressure tested, requiring specialist test equipment and calibrated gauges.
Low Pressure and High Pressure hoses
As far as the flexible connecting hoses are concerned, either the Low Pressure (from the cylinder mounted regulator system), or the High Pressure (from the cylinder to the regulator on bulkhead mounted systems) there are two types of hose, obviously, Low Pressure and High Pressure. It is not permitted to substitute a Low Pressure hose in place of a High Pressure hose, but a High Presure Hose can replace a Low Pressure Hose.
Fittings are different for the two types of installation:
For Low Pressure (after the cylinder mounted regulator) the hose must be fully pushed onto the spigot of the regulator and the spigot of the rigid pipework supplying the van, and MUST be secured at each end with either metal ‘O’ Clips or with Stainless Steel Gas Hose Worm Drive Cilps.
The Gas Hose Worm Drive Clips differ from standard Jubilee Clips in as much as they have a smooth inner surface which does not allow the worm drive to bite into the hose. These clips should only be tightened enough to prevent gas escaping, and not too tight to crush the hose or cause damage by being too tight.
High Pressure hoses(from cylinder to bulkhead regulator) MUST have swaged ferrules securing the hose to the M20 Nut at one end and the Propane or Butane fitting at the other. No other type of securing is allowed.
Current regulations for hoses
Low Pressure: Should only be long enough to reach the regulators on a two cylinder installation in the gas locker. High Pressure: a MAXIMUM length of 450mm, except for motorhomes with slide out tray mounted cylinders where 750mm is permitted. Both types of hose should be regularly inspected for damage, splitting, chafing, etc and should be replaced at a maximum of 3 years use. The date code on LPG hoses is the date of manufacture and properly stored the actual countdown use time starts from the first time gas is passed through the hose.
In case of emergency, know who to contact
In the event of smelling Gas, TURN THE CYLINDER OFF and call a suitably qualified LPG engineer. Not all Gas Safe engineers are LPG certified and a Natural gas engineer cannot work on LPG as a LPG qualified engineer cannot work on Natural Gas, unless they are dual certified.