There’s no better way to spend time with your friends and loved ones than hanging out on a deck, patio, or in the garden. Many homeowners install propane-fueled heaters on their patios to extend their usable outdoor hours.
These heaters provide instant warmth and ambiance in your home by bringing the indoor environment to your outdoor living spaces.
With a propane-fueled heater, it’s possible to spend long hours on your patio, more so during the colder months of the year. If you’re thinking about purchasing a patio heater, one question will run in your mind; how long does a propane tank last on a patio heater? Well, here’s what you should know:
How do Propane Gas Heaters Produce Heat?
Typically, heat production is measured in British Thermal Units (BTUs). Propane patio heaters are designed to produce 30,000 to 40,000 BTUs of heat.
There are different models of propane heaters, and the amount of heat they generate depends on their capacity. You can also choose a propane patio heater according to your space requirements.
Propane heaters are designed to generate heat instantly. The gas is contained in a pressurized tank, which keeps it in a liquid state. When you turn on your propane heater’s valve, the liquefied propane gas will become highly flammable gas. After that, the gas goes to the burner when you turn on the ignition, producing a flame that generates heat.
Breaking Down the Numbers
Propane patio heaters come in different styles and sizes. They are available in tabletop and portable models, wall and ceiling and hanging models, and standing models. It’s best to have an idea about the science behind gas heating to know how long a propane tank will last.
With this knowledge, you’ll never run out of propane, more so during those cold evenings when you feel like spending as much time as possible on your patio.
To estimate how long a full tank of propane will last, you must keep three things in mind:
- The number of BTUs that the heat source can produce
- The area of the outdoor space you want to heat
- The outside temperature
A typical propane-fueled patio heater consumes around 42,300 BTUs. Conversely, a full 20lbs propane tank contains about 432,000 BTUs. When you divide the tank’s BTUs with the heater’s BTUs, you get about 10.3 hours of heat.
Indeed, you won’t spend 10 straight hours sitting on your patio on a cold winter evening. The number of hours that your propane tank will last depends on the number of hours you light your heater, the difficulty you encounter when lighting it, and whether the tank was full in the first place.
How Much Heat Do You Need to Keep Your Patio Warm?
One of the factors that determine how long your propane tank will last is the size of your patio. To know how many BTUs you need to heat your space, you need to multiply your patio’s height, width, and length by the degrees you want to raise the temperature with.
For instance, if you have a 50 square-foot patio with 8-foot ceilings, it means you’ll be heating 400 cubic feet of space. Let’s say the outside temperature is 30 degrees Fahrenheit and you want it to be 70 degrees Fahrenheit on your patio, and you’ll need to raise it by 40 degrees Fahrenheit.
When you multiply these two numbers by .133, you’ll deduce that it takes slightly over 42,500 BTUs to maintain 70 degrees Fahrenheit for one hour.
It’s essential to understand your heating needs before finding out how long a propane tank will last you. A 20lbs propane tank holds around 432,000 BTUs. Each gallon of propane contains approximately 91,502 BTUs, and each pound contains roughly 21,500 BTUs.
Thus, a full 20lbs propane tank can heat a 1000 square foot patio for 10 hours straight.
The number of hours you’ll get from a propane tank depends on the specific heating application and the changing outside environment. Remember, most patios are not shielded from the elements. Therefore, the amount of gas needed to heat your patio also depends on the prevailing weather conditions.
Typically, outdoor heating spaces such as patios come with the challenge of maintaining the required temperature. Since these spaces tend to be open and vulnerable to the elements, the most a heater can do is increase the temperature of a specific area of the patio rather than the entire space.
Some propane gas also gets wasted when lighting and running a patio heater.
This also needs to be considered when calculating how long a full propane tank will last on your heater. The amount of propane that is lost depends on different factors. However, if you run your patio heater for three hours at a time and experience trouble lighting it, you’ll lose about 0.5 to 0.75lbs of propane per tank once or twice per tank.
How to Get the Most out of Your Propane Tank
It’s best to know how to get the most out of your propane tank to save on utility bills. In this regard, you should know about things that can reduce heating time on your propane-fueled patio heater. These include:
It’s a no-brainer that a bigger propane tank will give you more heating hours than a smaller one. Even if you use a standard propane tank that gives you about 10 hours of heating, you should ensure that it’s filled to capacity (20lbs).
Note, propane tanks are never completely filled 100%. Depending on the weather, it’s between 75% – 80% full. In most tank exchanges, propane will be added to your tank until it stops filling.
Afterward, remember a few re-fillers to measure the tank’s weight to ensure that it has 20lbs of propane. When you get a new tank of propane for your patio heater, ensure that it weighs a total of 20 pounds. This way, you’ll get the most out of it.
Lighting Technique and Prevailing Weather
A lot of propane goes to waste when lighting patio heaters. Besides, how full a tank is and the prevailing weather plays a significant role in lighting a patio heater. For instance, if your tank is half-empty and the weather is cold and windy, it will take more time and effort to start your propane heater.
If you use a new patio heater, it will take some time for the lines to expel the air. Thus, more propane will be needed to heat your patio. Likewise, if your heater is too old, the lines are likely to be dirty or corroded. Therefore, it will be challenging to light the heater or keep it on. Indeed, this means you’ll end up using more propane to heat your patio.
Running Propane Tanks at a Reduced Heat Setting
To get a few more hours out of a propane patio heater, the idea of running it at a reduced heat setting may cross your mind. But, one question remains; will this yield the desired outcome? Generally, manufacturers don’t advertise the lowered heat setting.
To put this into perspective, we’ll convert a patio heater’s output into a percentage. If the maximum output is 100%, a reduced setting would be 50%, for instance. If you set your heater at this level, the BTUs will correspondingly reduce by half. Therefore, you’ll improve your tank’s longevity.
Even as you reduce your heating costs by lowering the heater’s settings, you should remember that going below 50% affects the heater’s effectiveness. It will be difficult for the heater to radiate enough heat to warm your patio sufficiently.
Safety Concerns When Using Propane Patio Heaters
There are several safety precautions to keep in mind when using propane patio heaters. Propane is a highly flammable gas for starters, and therefore, should be handled with proper care. Before filling out your tank, check to ensure there are no leaks.
While checking for leaks, you should pay attention to the gas lines, fittings, and hoses because they are more vulnerable to leaks. Propane gas tanks also need to get serviced regularly. The smell of gas when using a propane heater indicates a leak. If this happens, turn off the heater and contact your local fire department immediately.
As a safety measure, propane tanks should be stored at least 20 feet away from the heater. This makes it easier for you to prevent actuating the heater’s safety relief valve when the tank’s volume expands.
Furthermore, propane tanks should be stored upright and at least five feet away from exits. In case your patio heater causes a fire accidentally, use its auto shut-off button. Most heaters automatically shut off when titled at 30 degrees.
Propane heaters are popular among homeowners who wish to spend more time outdoors. These heaters come with a considerable price tag. Even so, they help you spend more quality time outdoors with your friends and loved ones.
If you’re thinking about investing in a propane-fueled patio heater, it’s best to know how long a full tank of gas will last. This information helps you budget for your heating, besides enabling you to devise ways of reducing your heating costs. Be sure to checkout our article on how you can manually light your patio heater.