Light emitting diodes are constantly evolving and have reached the stage, in mid 2006, where they are suitable for the full lighting needs in your motorhome. This has not always been so, and they have had more limited special applications in the past.
RVs are complex machines containing both automotive and household systems to meet our varying needs and requirements. Not only must it carry us down the road from destination to destination but it must also provide all the comforts of home when we ultimately arrive at those destinations. For the most part it is “not connected” to support systems to meet those ongoing needs. We stop for fuel and oil occasionally to provide the automotive needs for our RVs. Similarly when we stop to spend the night at various locations around the country we are generally able to “plug in” to 240V ac (household electricity) to provide the basic electrical needs of our RVs, yet we must carry with us our household fuel requirements in the form of “liquefied petroleum gas”, LPG or, as it is commonly referred to, PROPANE. There are other “bottled gas” products that are quite similar to PROPANE that are also referred to as “liquefied petroleum gas”, thus, are often confused. The most common of these is BUTANE that is also a gas liquefied by pressure and utilised by various portable or mobile applications. Some of the differences will be discussed later where they relate to the RVer. The PROPANE that we carry generally provides the energy to cook our food, cool our refrigerators, heat our water, power our barbeque and run the generators in some RVs. Of course, we can only carry a limited quantity of PROPANE to provide for our needs for a limited period of time before we must refuel that system as well.
PROPANE is a very useful and convenient fuel for RV purposes. It has a unique blend of qualities that make it almost ideal for our mobile applications. When used carefully, including proper system maintenance, PROPANE is very safe, yet it does pose some risks, and demands understanding and special handling from RVers who utilise this fuel. Most RVs today contain from 4-27 kilograms of PROPANE which when combined with the automotive fuel (petrol or diesel fuel), represents a major potential fire or explosion threat. Thus, much of our concern and care should be to minimise that danger.
PROPANE itself is a derivative of the distillation process of the motor fuels and natural gas that we utilise in our vehicles and homes. It is one of the lightest factions of the fractionating procedure coming from that process as a gas. In order for it to be utilised as a convenient fuel it must be liquefied. This is accomplished by compressing the gas. To liquefy the gas it is compressed approximately 270 times by volume. As long as the “liquefied petroleum gas” is maintained under pressure it remains in the liquid state. For these reasons the storage and usage of PROPANE requires the use of heavy steel or aluminium tanks or cylinders capable of withstanding the high pressure required to maintain the gas in a liquid state.
PROPANE will produce approximately 25,000 BTUs of energy for each litre of fuel burned (20 litres per 9 kg). This high energy content produces more than adequate heat for use in the various RV systems without requiring excessively large quantities of the gas to be stored and transported by the RVer. In contrast BUTANE contains more energy (approximately 27,000 BTUs per litre) which would appear to make BUTANE a better choice for our RVs. However, BUTANE has the negative quality of not vaporising (boiling) at temperatures below -1°C (PROPANE will vaporise down to -42°C) making it impractical for RVs that occasionally must endure lower ambient temperatures. If the gas will not boil (vaporise), it will remain in the tank where it does no good.
No household fuel would be ideal for RVers if it were not widely available in every city large and small throughout the country. PROPANE has the distinction of having a very widespread distribution network throughout the country. That distribution network is in place not because of the RVer and his mobile lifestyle, rather it is there because PROPANE is in great demand for both mobile and fixed facilities throughout the country. Where natural gas is not available for household usage, PROPANE is normally the next best choice. In addition, many commercial and industrial operations utilise PROPANE because it burns clean allowing them to meet the ever tightening EPA requirements. Many companies view PROPANE as being just about the ideal fuel. LPG has also gained some acceptance as a motor fuel. It is commonly used in plant (indoor) environments and “on the road” where its clean burning qualities are appreciated.
In order to be utilised in our RV appliance systems fuel must first be vaporised. It is the vapour of the fuel that is burned to operate those appliances. In this critical aspect PROPANE excels. PROPANE is easily vaporised at any temperature above -42°C because the liquid gas in the cylinder boils above that temperature providing the gas vapour that we require for the appliances. The conversion to the gaseous state requires no energy from the system and does not decrease the available fuel. Vaporisation does result in a chilling of the PROPANE system; however, at the limited range of usage in most RVs, that chilling does no harm and will easily dissipate into the atmosphere. In very cold conditions the slowed rate of vaporisation combined with the low ambient temperature might result in the PROPANE system freezing up, not providing adequate quantities of gas to meet our needs. Note that the empty space reserved at the top of the PROPANE cylinder is there to provide room for the liquid gas to vaporise and to accommodate the expansion of the liquid PROPANE when the outside temperature rises. These are the reasons that PROPANE cylinders are limited to 80% of their volume when filled to the maximum level permitted by law.
Historically, PROPANE has always been a reasonable value in terms of its cost per BTU of heat content. To a large degree this was a result of the fact that PROPANE is a by-product of the production of automotive fuels that are in far greater demand. When combined with the limited usage of PROPANE the result was an over supply and a relatively low price. With the event of the tightening of EPA regulations resulting in a greatly increased industrial demand, combined with the change in demographics around the country where more and more households are opting for a rural lifestyle, the demand for PROPANE is burgeoning. With that increase in demand the case has risen often to the point where the fuel is actually more expensive than its primary competition – natural gas. To the RVer the cost of the PROPANE is less a concern than its distribution network and convenience of use.
With virtually every RV using PROPANE day in and day out as its household fuel of choice, RVers know that PROPANE is both safe and convenient. Yet worldwide every year many RVs are damaged or destroyed by fire and explosion directly related to the PROPANE system. Further, many more RVs are damaged to a greater extent because of the PROPANE carried on board the RV when a crash or incident triggers involvement by the PROPANE. One common illustration of this secondary involvement is that PROPANE lines are sometimes run through or adjacent to the wheel well in our RVs where a blown tyre or thrown tread could break the line, possibly resulting in fire. Knowledge of PROPANE and its proper usage and handling along with a full understanding of RV weight and tyre issues are generally adequate to virtually eliminate any risk.
RV and mobile home PROPANE systems are designed for long, safe and trouble free operation. A tremendous amount of engineering effort has gone into the prevention of PROPANE accidents. The safety record of the industry proves the adequacy of those efforts. PROPANE gas has an odour added providing its users with its most important safety feature. The offensive garlic smell is unique and should alert you to the presence of PROPANE. If the odour is present take immediate appropriate action to counter the danger of fire or explosion. We will have much more on PROPANE safety in a later edition of The Wanderer.
Many RVers use camp stoves, barbeques and outdoor lights which are also powered by PROPANE. In this case the PROPANE generally does not come from the RV system, rather it may come from small disposable canisters. The usage of these disposable canisters could not be simpler. They are merely screwed in place and disposed of when depleted. The canisters are readily available from hardware stores and wherever sporting goods are sold and can be stored for some period of time before being used. The disposable PROPANE canisters are very trouble free in operation; however they still contain a significant amount of potential energy, thus they should be treated with care.
• Treat disposable PROPANE canisters with the same respect you treat your RV PROPANE system.
• Remove the fuel canister when not using the appliance.
• Do not attempt to refill the PROPANE canisters.
• Store PROPANE canisters outside the living area of the RV.
• Keep canisters away from heat sources.
• Dispose of used canisters properly.
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