Bill Ward, Owner of Hallmark RV, helps to demystify the safe use of propane and propane systems in a truck camper. Crack the petroleum, it’s a gas!
When we got our very first used truck camper, we spent the night at Gordon’s grandparent’s house to test out the systems before hitting the road. At about 2:00am the propane / LP detector started beep, beep, beeping at us. Of course we freaked out and ran out of the camper thinking it was going to explode.
Flashlights in hand, we poured through the bag of manuals that came with the camper looking for some answers. A few frantic moments later we read that propane / LP detectors will go off if your camper batteries are too low. We checked our batteries and sure enough, they were low. We weren’t about to explode after all. A few laughs later, we went back to bed.
Ever since that event, we’ve heard countless stories about other newbies who have had similar experiences. Obviously we needed to address proper propane use and safety in a truck camper. When Bill Ward, Owner of Hallmark RV, confessed that he was very interested and knowledgeable about the subject, we had finally found our expert. The following article is the result of our conversation with Bill.
Update: Following the initial publication of this article, Manchester Tank and Equipment, contacted us with some further insights into this important subject. With their help, we updated the article with more information on propane system maintenance and safety.
What is propane?
Propane, also known as liquid petroleum gas, LP-gas, and LPG, is produced in roughly equal amounts from both natural gas and crude oil sources. Propane is nontoxic, colorless, and odorless until an odor similar to rotten eggs is added to allow the gas to be quickly detected. Knowing this smell is very important to your safe use of propane.
To make propane from crude oil, the oil is separated at a refinery using a fractioning tower. Propane is refined into different levels of purity depending on what height of the fractioning tower the propane is pulled from. The higher the point on the fractioning tower, the higher the purity, or quality, of the propane.
In the warmer southern states, you are buying propane with more butane, which is at a lower cut point, or crack of the fractionating tower. In the colder states, you are using a propane that is from a higher crack that is more pure, therefore it can be a little more expensive.
Propane bought in a more tropical climate is not going to be as pure and therefore will not be the quality of propane you need to camp in a colder climate. That means that if you are traveling from a warmer to colder climate, you should use up your propane before getting to the cooler weather.
The quality of colder weather propane is better, so people traveling from cooler to warmer climates are fine. It’s also okay to mix propane from cold and warm climates. The general rule is to use propane from the climate you are in.
Truck campers have either horizontal or vertical DOT (Department of Transportation) propane cylinders (also known as containers or bottles). It is very important to use only vertical DOT propane cylinders in campers designed for vertical cylinders and horizontal DOT propane cylinders for campers designed for horizontal cylinders. If a propane tank has a collar with a stamp and you can pick it up, it’s a DOT propane cylinder.
Inside a DOT propane cylinder, there is a fixed maximum liquid level gauge. There is also an overfill prevention devise, or OPD, that acts a like a toilet float to prevent overfilling. These mechanisms are oriented for horizontal or vertical use in horizontal or vertical propane cylinders. This is why it’s critical to use the correct vertical or horizontal cylinder in your propane system. Horizontal DOT propane cylinders are easy to recognize as they have feet on them.
There is a lot of information on a propane cylinder including the date the cylinder was manufactured. Propane filling attendants look at this date to know how old your cylinders are. Different states have different regulations on how old your propane cylinders can be. For example, in Colorado, the regulation states that propane cylinders can be no more than twelve years old.
Bill explained that propane cylinders should only be filled to 80% capacity. It’s extremely important to not overfill a propane cylinder as it could allow liquid propane into your propane fueled appliances. Not only could this be a fire hazard, but it could also freeze and damage propane regulators.
Propane expands 1.5% for every ten degree increase in temperature. As a liquid, propane doesn’t compress like a gas and needs room to expand safely. By filling your propane cylinders to 80%, you prevent this potential expansion from creating a dangerous situation.
For example, say you filled your propane cylinder to 92% when you started your trip in Minnesota. At the time you filled your tanks, the temperature was 30 degrees fahrenheit. From there you drove to Florida where it was 70 degrees fahrenheit. The propane liquid expands with the rise in temperature until the relief valve discharges propane. This discharge of liquid propane is dangerous and could fuel a fire.