Almost every new RV model comes with a propane tank because it is an essential fuel source for every camper. It is very important to carefully plan your RV’s propane consumption, especially if you can’t get to a gas station shortly or you’re boondocking. But, how do you plan it? And how long does a propane tank last in an RV? In this article, we’ll talk about that and much more. So, let’s get started!
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How Long Does Propane Last in an RV?
So How Long Does Propane Last in an RV? Typically, a 20 lb propane tank can run in your RV for 10.5 hours, a 30 lb propane tank can run for 16 hours, and a 40 lb propane tank can run for around 21.5 hours. Keep in mind that a 20 lb propane tank has 4.6 gallons of propane, where one gallon of propane consists of 91,502 BTUs.
Below we will go through these things in detail and explain to you which parts you still need to pay attention to. This is also an interesting thing that you should know about RVs, so be sure to read How To Turn On Electric Water Heater in RV? Expert Explain.
Most Used RV Propane Tank Sizes
The first thing before we start calculating the total RV propane usage is to compare the different size possibilities for RV tanks. Manufacturers usually list the size of propane in pounds and/or gallons and you can find it in a propane tank cylinder.
- Gallon measurements are the indicator of the total amount of propane that will fit inside the tank.
- Pound measurements tell the total weight of the cylinder when the propane is full.
In most cases, when buying a tank, the first thing that you must notice is the pounds. Keep in mind that knowing the number of gallons will help you into calculating your propane consumption which we’ll discuss further below.
Note! A propane tank that is “full” is only 80 percent full. The remaining 20% provides area for the liquid propane to expand. Why is that? Well, the liquid propane needs area in which it can be expand.
Here are the 2 most used propane tank sizes for RVs:
- 20 pounds: When full, it contains 4.6 gallons of propane so it can be easily refilled and it’s the best option for people who don’t use a lot of fuel.
- 30 pounds: Even though it is a heavier alternative it is still portable and easy to refill. It comes with about 7 gallons of propane when full.
Keep in mind that there are also 11, 40, and 100-pound propane tanks available. When you find out how much propane your RV uses, then you’ll get a much better picture of how long can a propane tank last. In some cases, the currently installed propane tank is not enough for your current appliances, so you’ll need to add a second tank in your RV as a backup.
How Long Does Propane Tank Last in an RV?
Determining how long your tank of propane will last, usually depends on a few factors. Although propane is the most important fuel source for your RV it isn’t the only one. Electricity, also, has a significant role in your RV’s energy use. Despite the fact that the majority of appliances are powered with electricity, still, some of them also run on propane. To resolve how long does propane last in RVs you need to learn about the following elements:
- Propane tank’s capacity
- How frequently do you use your appliances
- The BTU rating of total propane appliances
BTU (British thermal units) measure the heat content of fuels or energy sources. We are not going to complicate and go deep into BTU measurements just to let you know how to estimate your propane usage. Just know that is the BTU rating of each propane-powered item in your RV and that:
- 1 gallon of propane consists of 91,502 BTUs
- 1 pound of propane consists of 21,548 BTUs
Multiply that number by the total number of BTUs in your tank to get the total number of BTUs in your tank. After you’ve calculated your tank’s overall BTU capacity, divide it by the BTU usage.
- Propane in gallons X 91,502 = Total Tank BTUs
- Tank total BTUs / Total BTU usage = Hours how long propane will last
Tip: You can take a look at the owner’s manual or if you are lucky you will find the BTU information on a tag that is attached to the device.
Hopefully, you now have a clear image of how to determine how long your propane tank will last. Keep your eyes open! The following example is going to help you understand much better this. RVs propane-motorized mechanics consist of:
- A furnace is rated at 30,000 BTUs
- A water heater is rated at 8,800 BTUs
- A typical RV fridge is rated at 1,200 BTUs
We’ll simply assume that your RV uses equally propane for these appliances to avoid any complications. All of those appliances (water heater, fridge, and furnace) use approximately 40,000 BTUs of propane. Keep in mind that the energy that you use will depend on the number of hours that it will be used. Now, let’s use a simple example with different propane tanks of different sizes.
How Long Can a Propane Tank with 20 LB Last in an RV?
Here we’ll use an example with a 20 lb propane tank that comes with 4.6 gallons. We already mentioned that 1 gallon of propane consists of 91,502 BTUs. So here we have the simple calculation formula:
- 4.6 (gallons) x 91,502 = 420,909
- 420,909 / 40,000 BTUs = 10.5 hours
With that calculation, we’ll get that a 20 lb propane tank can run for 10.5 hours before it runs out of propane.
How Long Can a Propane Tank with 30 LB Last in an RV?
In this example, we have a 30 lb propane tank that comes with 7 gallons when it is completely full. So, in this example we’ll use the same calculation formula:
- 7 (gallons) x 91,502 = 640,514
- 640,514 / 40,000 = 16 hours
That means a 30 lb propane tank can be turned on for 16 hours before needing to be refilled.
How Long Can a Propane Tank with 40 LB Last in an RV?
Lastly, we’ll have an example where we have a 40 lb propane tank that comes with 9.4 gallons of propane. We’ll use the same formula:
- 9.4 x 91,502 = 860,119
- 860,119 / 40,000 = 21.5 hours
In this case, we’ll have that a 40 lb propane tank runs for around 21.5 hours before it runs out of propane.
RV Propane Usage Calculator
The best way to calculate how long the tank of propane can last is by using basic data. The first step is to enter the number of gallons that your propane tank has with the total BTU usage in your RV. Most owner manuals have the BTU usage of each appliance. With that data, you can calculate RV propane usage. Here is the simple process in three steps:
- Enter the number of gallons of propane in your tank
- Enter the total BTU usage of your RV’s gas appliances
- Click Calculate
For ease of understanding, we prepared this table of classic RV propane tank sizes and how many gallons they store when full.
|Size of RV Propane Tank||Gallons (When It Is Full)|
|11 lb. tank||2.6 gallons|
|20 lb. tank||4.6 gallons|
|30 lb. tank||7 gallons|
|40 lb. tank||9.4 gallons|
|100 lb. tank||25 gallons|
How Can I Make My RV Propane Last Longer?
One of the ways on how you can save propane and energy costs is by conserving them. In the following section, we’ll give you a few tips on how your propane can last longer.
Tips and tricks to save your propane:
- Insulate your RV: One way to boost the efficiency of your propane tank heat, you could simply to add additional insulation to your RV doors and windows. Furthermore, using an RV skirt will be a great contribution to insulating your RV and preventing propane waste.
- RV appliances must be used with caution: Any appliance that uses propane needs to be used wisely. You need to be extra careful. For example, using a hot water heater that runs on propane-powered requires you to take quick showers. If your using your RV during cold winter, it is recommended to use the electric heater instead of a propane-powered furnace. Therefore, be careful about how you use your propane appliances in your camper.
- Use a propane regulator: By using this regulator you can balance the amount of pressure discharged from the tank. The regulator will assure the appropriate amount of propane to your appliances so they can function properly.
- Reffil Your Tanks over an exchange: Your propane will eventually run out. There is no way to stop it, you can only slow it down by frequent use. When the time comes, you can always go and look out for a new tank, but don’t rush on that decision. That isn’t always necessary, especially if your tank is damaged or close to an end (tanks do have an expiration date). Choose to refill rather than exchange. This will give you 25% more propane and it is also cheaper.
- Regular Propane Tank Maintenance: Regular maintenance is very important when it comes to propane tanks. Look for any kind of damage that might cause leaking or something worse. Don’t forget to do a check-up during refill and during usage. Make sure your RV propane detector is in good working order by testing it on a regular basis. Another good preventative maintenance task is consulting an expert so you can get the best from your propane tank.
How To Know If Your RV Propane Tank Is Empty?
To be sure if your RV tank of propane is empty get yourself a propane tank gauge from Amazon or a home improvement store. It will cost you less than $20! For those who don’t know – Tank gauging is the generic name given to the measurement of liquids (products) in bulk storage tanks with the aim of quantifying how much propane is available.
Some regulators can keep an eye on the levels in your tank, and some of them will even swap the tanks when the first one runs out of fuel. For example, we have The Flame King model and one great advantage of it is that the indicator changes color when it’s time to refill your tank. Create some kind of a habit and check the gauge as part of your regular visual checks.
For those without a gauge, we have a solution for you! There is another option that you can use besides having a gauge to measure the tank fuel level. That method is by using hot water. Follow these steps:
- Find a bucket and fill it with hot water.
- Slowly pour that water into the tank’s edge. (pour the water, not trickle it)
- Vertically run your hand along the tank’s side. As you do this, take note of any temperature changes.
- The tank top needs to be warm. If yes, this implies that there is no propane in the tank where you are touching it. (If you don’t notice any changes, your tank is probably empty.)
Be sure to watch this video to learn more tips and tricks for your propane tank to last longer:
For those who want to know more about RVs, be sure to read How Does an RV Propane Furnace Work?
FAQ: People Also Ask
How long can 30lb propane tank last in winter?
You can expect that a single 30 pounds propane tank lasts for a few weeks to a month or even more if you are not using it regularly (keep in mind that you are using gas for the fridge and hot water heater).
What does it cost to fill a 30lb propane tank?
The average price of a 30 lb propane tank is between $22 and $28. On the other hand, the previous few times I pay $22-$24 for a 30 pounds cylinder. It usually depends where you live.
Almost every RV comes with a propane tank. As each RV contains various appliances such as a refrigerator, stove, and boiler, a certain amount of propane is needed for them to work. It is therefore good to know how long they last so that you can replace them regularly when they run out. In this article, we went through everything related to this topic and explained to you how you can calculate it yourself. If you have any more ambiguities, feel free to contact us.