LPG Burner Maintenance: Differences from Natural Gas

The fundamental difference between LPG and natural gas: density

LPG (a propane/butane mix) is noticeably heavier than air. On a leak, it does not rise and disperse like natural gas — it settles and accumulates at floor level and in low points. This directly affects where the site's gas detector should be positioned: on natural gas sites the detector sits close to the ceiling, while on LPG sites it should be positioned close to floor level.

Storage and vapourisation: an LPG-specific consideration

LPG is stored as a pressurised liquid in the tank and delivered to the point of use as vapour. The rate of vapourisation depends on ambient temperature — it slows at low temperatures. On high-consumption sites (particularly in winter), there's a risk of tank pressure dropping and the burner receiving gas at insufficient pressure. On larger-capacity sites, a vapouriser can be used to prevent this risk; where fitted, its presence and condition should be included in the maintenance scope.

Differences on the burner side

• Nozzle/orifice: LPG and natural gas have different combustion characteristics; the burner's gas head and nozzle must be sized by the manufacturer for the specific fuel in use. Checking these components is essential when converting from one fuel to the other.
• Regulator: a dedicated LPG pressure regulator is used; it is not interchangeable with a natural gas regulator.
• Combustion setting targets: as covered in our flue gas analysis guide, LPG's theoretical maximum CO₂ differs from natural gas's (around 13.7% for LPG versus around 11.7–11.8% for natural gas). A measurement taken with the wrong fuel type selected on the analyser gives a misleading result.

Safety: LPG behaves differently on a leak

• If a gas smell is noticed, unlike natural gas this is a gas that settles rather than rises; when leaving the area, stay clear of low points (basements, sunken areas).
• Do not touch electrical equipment, and avoid anything that could generate a spark.
• Safety clearances around the tank and valve from ignition sources must be observed — these clearances are defined in the applicable LPG installation standards and regulations.

LPG-specific additions to the maintenance checklist

In addition to our standard maintenance checklist, LPG sites should also have the following checked:

• Tank pressure and level
• Signs of regulator freezing (icing on the regulator can appear during periods of unusually low pressure — a sign of insufficient vapourisation capacity)
• Vapouriser condition, where fitted
• That safety clearances around the tank and valve are being maintained