What Does a Generac Generator Run On? (Detailed Guide)

What Does a Generac Generator Run On

A Generac generator is, without a doubt, a great option for powering homes during outages. In fact, it is the first choice of thousands of people looking for standby generators.

I have been using it for more than three years now and have no complaints. However, those who haven’t purchased it yet or recently bought it often search about what it runs on. Well…

A Generac generator can run on two fuels- Natural gas and Liquid propane. It is factory reset to be powered by natural gas, but you can change it to liquid propane by following the manual or getting help from a professional.

But there’s much more. It’s crucial you know how long you can run your generator and what precautions to take if you don’t want any problems to arise. So, stick to the end.

What Does a Generac Generator Run On?

What Does a Generac Generator Run On

As I discussed above, Generac Generators run on Natural Gas and Liquid Propane. Both have their set of advantages, and it’s time to find out about them.

Natural Gas

What Does a Generac Generator Run On

Most people prefer to run Generac generators on natural gas. Since it is a standby machine, it is easier to connect it to the home’s gas supply line.

As a matter of fact, Generac generators are factory reset on being used on “Natural Gas.” If you want to use liquid propane, then you will have to reconfigure the machine’s settings.

So, what advantages will you have when you use Natural Gas as a fuel to power the Generac Generator? Well, these are:

Natural Gas is Cheaper than Gasoline

Gasoline is expensive nowadays. That is why I have stopped using my portable generator and switched to the standby one. Fortunately, natural gas is affordable.

No Rescheduling Headache

Another reason I like Natural Gas is that there are no refilling commitments. When the electric supply goes down, the generator will start automatically and will keep running until the power gets back up. Everything happens without you doing anything. So, it’s reliable and time-saving.

It’s Clean

I read an EIA (US Energy Information Administration) article on Natural Gas and it says that it is environmentally friendly than other hydrocarbon fuels. Note that the sulfur and toxin emissions are also lower than gasoline. So, it’s a safe choice for the neighborhood.

Liquid Propane

What Does a Generac Generator Run On

Liquid propane is the second fuel you can use to fire up the Generac generators. In most cases, those who don’t have natural gas service in their homes choose to go for it. But this does not mean liquid propane is a bad choice.

Here are the benefits of using it to power up the Generac generators.

Long Shelf Life

Propane fuel has a long shelf life because it is stable. To your surprise, it can stay good indefinitely if you follow all the care measures. In comparison, gasoline stays stable for around six months on average.

Clean Burning

Propane burns smoothly without emitting air pollutants. It also releases low carbon and nitrogen oxide than most hydrocarbon fuels as well.

Can Store Easily

Storing propane liquid is simple. You can fill it in any good-conditioned container, and it will stay stable.

However, I have noticed that propane liquid can go bad when you store it in rust or corroded containers. Plus, if you place them in congested areas, the chances of fuel getting spoiled are also more.

But liquid propane maintains its quality in most cases, so don’t feel hesitant to store it.

So, confused about which fuel to go for? I’ve been there. Continue reading to know what to do.

Which Fuel Should You Use to Run Generac Generator?

What Does a Generac Generator Run On

In my opinion, natural gas is a better choice for Generac generators because of two simple reasons.

Reason 1: Natural Gas is Generator’s First Choice

The company sets the default settings of Generac generators on “Natural Gas.” It means you can install it outside your home and start using it straight away. But if you want to go for propane, you will have to get assistance from an expert to change the settings.

So, why go for this hassle unless there is an emergency? Simply connect it to your gas supply line and become stress-free.

Reason 2: Can Run Indefinitely

The running time of Generac generators differs depending on which fuel you prefer. If you have gone for natural gas, then you can run it for as long as you want. The generator can stop only when the gas supply gets restricted.

But if you have chosen liquid propane, then you must be careful about how much fuel is left. According to my estimate, a 500-gallon tank Generac generator can run for about seven days non-stop.

But if you go for natural gas, you won’t have to fill the fuel every other day. You can simply connect your gas supply to the generator, and your job is done.

But wait.

Note that choosing the right fuel is not enough for Generac generators. There are some precautions you must follow if you want to stay safe.

Related: What Are The Pros And Cons Of A Whole House Generator?

Which Precautions to Take When You Run a Generac Generator?

Safety always comes first, no matter what you do. So, follow these preventive tips to avoid problems.

Read the Manual’s Instructions

What Does a Generac Generator Run On

The most important tip I have for you about Generac generators is to always read the manual completely. It contains all the information you must have before you use the generator.

Doing this will avoid problems in the future and will ensure the machine keeps running.

Furthermore, the manufacturer has also mentioned all the maintenance you should do to ensure the Generac generator operates smoothly. It is mainly about oiling, cleaning, and some other basic stuff.

Moreover, there is also a precautionary section in the manual that you should read carefully.

Focus on Fuel Safety

You should ensure that the propane tanks are stored and secured in an upright position. Remember- never put the fuel barrel horizontally on the ground.

Also, place the container on an even surface. It is because it can fall and start leaking if you put it on a sloped surface.

Ensure Proper Ventilation

What Does a Generac Generator Run On

Although this machine does not have high emissions, still, if you keep it in a closed space, the gasses can build up. Spending time in such a space can harm your health.

Furthermore, if the area is not aerated, the heat can also start to build up. High temperatures can damage the components, and you may have to call a repairman or get a new generator if you don’t do anything about it.

That’s why I recommend my readers always install Generac generators in a well-ventilated area.

Keep Flammable Materials Away

I have noticed that most people make the mistake of putting flammables near the generator. This is a hazard for you and your neighbors.

You never know- there are chances that something sparks and fire breaks out.

The things that are flammable are:

  • Fuel
  • Chemicals
  • Combustibles

Always Call a Professional to Install Generac Generator

What Does a Generac Generator Run On

People think that they can easily install/setup generators without any prior technical know-how and skill. That’s wrong! I have seen most of them mess up the process, which damages the machine.

In this situation, the generator cannot run for long.

Therefore, I always recommend getting assistance from a professional.

Use Carbon Monoxide Detectors

We all know that carbon monoxide has several health impacts. It can impact the lungs, cause breathing problems, damage sinuses, and do much more.

To some extent, generators also emit this gas. Although the intensity is not as severe as to cause any harm, I still put a carbon monoxide detector next to my Generac generator.

If the detector shows any alarming reading, it means the ventilation is poor, or there is something wrong with the generator.

In this case, call in an expert and follow what he recommends.

Inspect Regularly

What Does a Generac Generator Run On

The last precautionary measure I have for you is to always inspect your generator regularly. Check whether there is any dirt or debris on it. Furthermore, if it starts to spark or heat up more, it means there is an issue.

Keep in mind that a generator starts to make more noise when it is facing any issue.

Here’s what I do- I weekly check:

  • Fuel lines
  • Connections
  • Fittings.

I look for any leakages or damages because that’s where the problems usually begin.

So, start by examining these things and keep an ear on the noise level the generator makes.

If you follow my suggestions, your generator will keep on running smoothly for years.

Related: Is A Kohler Generator Better Than A Generac?

Final Words

All-inclusive, a Generac generator runs on natural gas or liquid propane. I prefer natural gas because it is cheap and requires less hassle. Plus, you can power the generator for as long as you want on it.

However, if you don’t have natural gas service at your home, you can go for liquid propane. A 500-tank generator can run for seven days.

Remember- Always take precautionary measures if you want to keep using your Generac generator.


Hi, Welcome to Generatorrookie.com; My name is Shahzad, and I know about generators because I grew up in a country where power outage is very common. I share Tips, How-To, News, and Reviews for the best generators or anything related to generators.

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