Going for Gas: How to Fill Propane Tank on a Motorhome

Propane is a source of heat and power for many motorhomes and travel trailers. While it typically lasts a long time—especially in appliances such as refrigerators—propane will eventually run out. When facing an empty propane tank, you might have a few questions. From what type of container you have to the different ways you can top off, here’s everything you need to know about how to fill a propane tank on a motorhome.

Types of Propane Tanks on RVs

Two types of propane tanks are available: DOT cylinders and ASME tanks. Propane tanks on RVs supply energy to refrigerators, stoves, air conditioning units, and heaters.

DOT cylinders are Department of Transportation approved options while ASME are American Society of Mechanical Engineers tanks. Motor homes typically have built-in ASME tanks on the underside of the vehicle. Most travel trailer units, fifth wheels, and other tow-behind options have removable DOT propane tanks.

Propane tanks come in many different sizes. Generally, the size of the motorhome dictates how large the propane cylinder is or whether there is more than one. RVs for sale usually come with full propane tanks—if not, ask the dealer or seller to fill them for you.

A small travel trailer may only use a miniature-size propane tank for a travel grill or small heater. Larger motorhomes typically have a 20-pound or larger propane cylinder. A 20-gallon size tank holds just under five gallons of propane. The amount of use you get out of a tank will vary widely and depends on a few factors:

  • What appliances you run
  • Whether your refrigerator is propane or electric
  • Whether your heater is propane or electric
  • If your stove is propane or electric
  • What type of power the AC unit uses
  • If you have a gas generator on board
  • The exterior temperature and weather conditions

Depending on the RV price, you can expect propane tanks to come as part of the package. Upgrade packages may be available with larger-capacity tanks.

Propane Tank Parts on RVs

Propane cylinders have a few main parts regardless of whether they are on a motorhome or not. Propane tanks must have an Overfill Protection Device (OPD) for safety. The OPD ensures the container cannot overfill; it shuts off propane flow when the reservoir is full.

ASME tanks have a built-in gauge while DOT types often require an aftermarket accessory for measuring propane levels.

Tank Holders on RVs

Propane tank holders ensure your fuel doesn’t move while you travel. You should never transport a full propane tank inside your vehicle. Instead, secure the tanks where the manufacturer specifies. In some travel trailers, propane tanks affix to the hitch area. Most motorhomes have storage underneath for tanks. Tank holders can contain one or two cylinders of various sizes depending on the configuration.

Propane Tank Covers

Tanks which stow outside the RV may come with a tank cover. Keeping the cylinders safe from the elements preserves them from weather conditions. You may even avoid rust and road grime with a snug propane tank cover. If your RV doesn’t come with one, you can purchase an aftermarket option to suit the size of your unit.

Changeover Valves

For recreational vehicles with dual propane cylinders, the equipment on your rig may include a changeover valve. A changeover valve can be either manual or automatic. If your RV doesn’t come with one, you can buy and install one for use with dual cylinders.

Options to Refill the Propane Tank

Sometimes it’s inconvenient to try and maneuver your motorhome into a propane filling station. Fortunately, moving the rig isn’t the only way to top off on propane. Here are options for refilling your RV’s propane tank.

Parking at the Fill-Up Station

The first option is filling up on propane at a gas station or similar location. With an ASME tank, which mounts to your RV, you must drive to the station to refuel. Class A motorhomes, for example, typically have ASME tanks. An ASME tank doesn’t come off—but these are usually high-capacity tanks. You may not need to refuel regularly unless you rely on constant heating or cooling.

With DOT tanks, you may be able to fill them without removing them from the vehicle, depending on how they affix to the unit. Safety rules often dictate that you remove them from the RV, however.

Many RV parks and campgrounds have propane stations. Most involve staff who perform the task for you; self-serve propane is not typically possible. People who fill propane tanks have specific training and understand the dangers of handling the gas. Campgrounds may have unique rules regarding propane fueling, such as removing the containers from the trailer regardless of what type or size they are.

Replacing the Propane Tanks

Many grocery stores and gas stations have propane exchange areas for DOT tanks. Propane tanks are often behind a cage or locked door. You can exchange your empty propane tank for a new one. The only guideline is it must be the same size tank.

Of course, you want the same size as the one you’re swapping so that you can guarantee it will fit in your rig’s propane holding area. A tank swap may not be the most affordable means of obtaining propane. You may also avoid switching tanks if yours has features such as a fuel gauge and the commercially available ones do not.

Removing and Refilling the Propane Tanks

If you don’t feel like driving your motorhome into a tight spot, you can always remove the tanks to fill if they are DOT. You don’t have to trade in your cylinder if you bring it to a filling station. At a campground, you only need to remove the tank from your recreational vehicle and bring it to the propane filling area.

Safety Precautions for Filling Propane Tanks on Motorhomes

Propane safety is an essential consideration with recreational vehicles. The potential for leaks is always high, especially when removing a propane tank for filling. Here are safety precautions you need to follow when filling your RV’s tanks with propane.

Shut the Motorhome Off Completely

Turning off the motorhome can help avoid fire hazards. While great deals are available, motorhome prices are too high to take a chance with your investment. Ensuring the engine is off means less chance a spark will ignite propane fumes while fueling.

Make Sure Everyone Gets Out of the RV

Because of the flammability of propane and the potential for leaks in the system, everyone in the RV should disembark while refilling propane tanks. In an emergency, it’s easier if everyone is safely off the RV beforehand. It also ensures no one will inadvertently start the ignition or turn on an appliance which routes to the propane tank equipment.

Don’t Smoke or Start Fires Nearby

Like standard gasoline, propane is highly flammable. Avoid lighting a cigarette or campfire near operational propane tanks or ones you are filling. Gases can easily escape while you fill containers, and a spark can ignite a fire. RV insurance may cover fire scenarios, but why take chances when prevention is so simple?

Use the Proper Gear

If you are filling your own propane in the rare instance that it’s possible, use the right gear. Wear gloves to protect your hands and consider using eye protection as well. Handling propane can be dangerous, and any fluid or gas under pressure has the potential to explode under the right conditions.

Final Thoughts

Propane is a useful and often necessary part of the RVing experience. With the ability to refill propane tanks on the go, RVers can dry camp and go off-grid without sacrificing the comforts of home. Learning how to fill the propane tank on your motorhome is essential and helps you to RV more efficiently and confidently.