RV Propane Appliances
RV Propane is stored in portable and detachable cylinders, such as those on your barbeque --- or tanks, which
are permanently affixed to a vehicle.
Propane cylinders are filled by weight and the pertinent information for each individual cylinder is stamped on
the protective flange surrounding the valve. This information includes the empty weight of the cylinder (tare
weight ) and the water capacity in pounds and allows the re-filling attendant to calculate the exact amount of LPG
(Liquid Propane Gas) to put into the cylinder.
Most tanks and some cylinders are equipped with a bleed valve, that when opened, shows when the cylinder is
filled to 80%. However, the present valve on the cylinder may not be the original valve and may or may not be the
proper valve for that particular cylinder, possibly resulting in an over filled condition. Newer cylinders have the
OPD (overfill protection device) which mechanically prevents the cylinder from being overfilled.
A motor home tank is filled by volume using the 80% bleed valve to indicate the proper fill level. Motor home
tanks required to be equipped with an automatic valve that shuts off the propane flow at the 80% capacity level.
The bleed valve is an extra safety device that should be used in addition to the safety shut off valve.
Propane is an odorless, colorless gas that is heavier than air. The common "propane" smell is a chemical called
Ethyl Mercaptan that is added to propane to allow it to be detectable by odor.
Any person dispensing LPG in Canada must, by law, be certified by the Propane Gas Association of Canada by
successfully completing a training course in the safe handling of LPG.
Also, by law, it is an offense to fill a propane cylinder or tank beyond 80% of it's capacity and that law is in
place for a very good reason. Propane is stored in a liquid state by compressing it in a cylinder or tank. At 80%
full there is the remaining 20% of the storage capacity to allow for expansion of the liquid due to temperature
changes. If the tank is over filled this expansion room is decreased to the point that the built in pressure relief
valve will vent off enough propane to avoid tank rupture. If the cylinder is lying on it's side when this happened
it would vent off enough liquid propane to reduce the internal pressure to below the preset pressure of the relief
valve. When liquid propane is released it will expand to 270 times it's volume. Propane is heavier that air and
tends to collect at the lowest spot, such as the lowest deck of a ferry, where enough can be present to cause an
An LP gas inspection on a recreational vehicle or the installation of a new gas burning appliance should only be
preformed by a licensed RV Propane Gas Fitter and you have every right to ask for qualifications.
In short, propane gas is a clean, efficient and convenient fuel source and very safe to use when all safety
precautions are observed.
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