5 Ways to Turn Off a Whole House Generator

Whole house generators are commodities designed to provide power to your house or workshop in case of power outages. If you’re afraid of the dark or have essential appliances that can never be without power, a whole house generator is a saving grace. 

Turning off a whole house generator is pretty straightforward on most units. Simply switch the button or knob on your generator to the OFF position. Alternate ways to shut off a whole house generator include switching the breaker, turning off the gas valve, or pulling the electrical disconnect.

In this article, we’re going to take a look at the best ways to turn a generator off and when a good time is to shut it down. If you have a generator and have questions about it, then you’ve come to the right place! 

Different Ways to Turn Off a Whole House Generator 

There are several ways to go about turning off your whole house generator. The first way to turn a generator off is by following this step-by-step process. 

  1. Set the main utility disconnect found inside your house by the panel box to off. 
  1. Turn the outside disconnect off. The outside disconnect is located next to or near the generator and looks like a typical air conditioner disconnect. 
  1. Don’t rush the process. Allow your generator to cool down for at least a minute before completely shutting it down. 
  1. At the controller on the generator, turn the setting off. 
  1. Locate and remove the 7.5 amp fuse from the controller. Removing this fuse will ensure that there won’t be an accidental startup during maintenance. 

Going through this process sounds like a timely process, but it’s the best way to shut down your generator without damaging it or you. 

If you don’t want to go through all the steps of doing a complete generator shutdown and instead want to turn it off temporarily after your main power is back on, here are a few other ways to do just that. 

1. Turn the Knob or Switch On Your Generator to OFF

Whether portable or stationary, every generator has a knob or switch that says ON, Manual, or OFF. Turn this switch to the OFF position to start the shutdown process on your generator. The generator will then turn off on its own. 

2. Flip the Breaker Inside Your House that Controls the Generator to OFF

The main panel box inside your house that feeds electricity to your entire home will have a breaker slot labeled GENERATOR. This breaker is in the ON position by default. It’s in the ON position to ensure your generator will turn on during a power outage. To turn your generator off, flip the breaker to the OFF position. 

3. Remove the Outside Disconnect or Turn the Disconnect Breaker to OFF

Just like an air conditioner or any sizeable outdoor appliance, your generator should have a disconnect. This disconnect is a safety measure designed for the emergency shutting down of machines. It will often come in the form of a pull switch or a breaker panel. To turn off your generator, flip the breaker or pull the disconnect out. 

4. Turn the Gas Flow Valve of Your Generator to OFF.

Closing the gas valve is the least recommended method of shutting down a generator and should only be used as a last resort. If you can’t locate any electrical components mentioned above to turn off your generator, turn the gas valve to the closed position on the pipe feeding your generator. 

If installed properly, the gas valve should be next to the generator. If not here, then inside the house on the gas line feeding the generator. Turning this knob will take longer to turn the generator off as it will continue to use any residual gas, and it will also attempt to continue running even after you terminate the flow of gas. After two or three false starts, the generator will finally shut down. 

5. Pull the Handle Inside Your House that Controls Power to the Generator 

Most generator installers will install the unit with the addition of a transfer switch. This switch is essential to the proper operation of your generator, and you can use it to turn the generator off. 

Should You Turn Off Your Whole House Generator at Night?

While it’s not required to turn off your whole house generator at night, it certainly isn’t a bad idea. Turning your generator off at night when you’re not using it will save gas and make for a more peaceful night’s sleep. Generators are loud appliances, and if you live in a busy neighborhood with houses packed together, your neighbors will appreciate the gesture as well. 

If you’re in the middle of a heatwave or the middle of winter, however, you’ll probably want to leave your generator on. By turning your generator off, you’re also turning off your furnace, air conditioner, water heater, and every other electrical appliance in your house. Turning your generator off is fine if you can do without these commodities, but be aware of the ramifications. 

When Should You Turn Off Your Generator? 

You can and should turn your generator off occasionally. However, if you have vital electrical appliances, ensure that you can do without power before shutting off your generator. Here are a few instances when you should always turn off your generator. 

Refilling Your Propane Tank

A whole house generator will operate on either propane gas or natural gas, depending on what the rest of your house gets. Natural gas generators will run forever until you turn them off, but you can shut down propane-powered generators manually to refill your propane tank. You should never run any gas appliances when filling a propane tank. 

Changing the Oil In Your Generator

Generators are like all other appliances with engines, and they require regular maintenance and oil changes. Changing the oil on a generator isn’t especially difficult, but it does require shutting down the appliance to do so. 

Cleaning or Maintaining Your Generator

You should only do any other cleaning or maintenance after turning your generator off. You should also allow your generator to cool down before touching it because it will most likely be red-hot after running for any length of time. 

Doing Electrical Work In Your Home 

Any time you’re working with electricity, you run the risk of electrical shock. Electrical shock can cause severe injury or death, so take every precaution before working on live electricity. Electrical maintenance includes doing electrical work on your generator or on the electrical panel that controls your generator inside your house. Make sure you turn your generator off so it won’t start up accidentally as you’re working on the electrical components. 

What’s the Best Way to Turn Off a Whole House Generator?

The best and safest way to shut off a whole house generator is to do a total and thorough shut down. Here is a step-by-step process of how to complete this type of shutdown. 

  1. Turn off the transfer switch inside your house that controls the power transfer from the main power grid to the generator. 
  1. Turn the outside disconnect switch off that controls your generator. This disconnect switch should be located close to the generator and is in the form of a breaker switch or a pull-out switch. 
  1. There is a knob or switch on the generator itself that says Manual, ON, or OFF. Turn this knob or switch to the OFF position. 
  1. Remove the 7.5 amp fuse on the generator that allows it to operate. 

By following each of these steps, you will ensure a complete and total shutdown of power. Make sure you give the engine a minute or two to cool down before touching it. If it’s still scalding-hot, then give it as long as it needs to cool down. It’s very easy to burn yourself by touching a hot engine prematurely. 

How Long Can You Run a Generac Whole House Generator? 

You can run a Generac whole house generator until it runs out of gas or until you need to shut it down for maintenance work. Think of your generator the same way you think of your air conditioner or furnace. Unless you turn it off or disconnect power to it, the generator will run non-stop. 

If you power your generator with natural gas, you have an unlimited gas supply, and your generator will run until you turn it off manually. Turning your generator off is done for several reasons, including changing the oil, cleaning it, or performing electrical service on the house it’s powering. 

If you have a propane tank that provides fuel to your generator, then you will turn it off every time you refuel. Your generator will also turn off automatically if it runs out of fuel, which is a good sign that it’s time to refill your tank. Depending on the size of your propane tank, you can run a generator continuously for 150 to 200 hours if the tank will allow it. 

You may also have to shut down your generator periodically for the engine to cool. The design of newer generators allows them to run on less oil and with cooler engines, which means that depending on the kind of generator you purchase, this won’t be an issue. You don’t have to shut down newer generators to cool their engines, while older ones need to cool down every eight to ten hours or so. 

The last thing you want to do is overheat your generator’s engine. Overheating will cause damage to the generator engine as well as the generator itself. These repairs are pretty costly, so make sure you check your owner’s manual to see if your generator needs to cool down from time to time. 

How Long Can You Run a Generator Without Shutting It Off? 

You can run a generator for as long as you need to without shutting it off. Reasons for shutting a generator off include running low on fuel or needing to perform maintenance on the unit. Changing the oil every 50 hours of use is a good idea, so that’s every day and a half if you’re running the generator around the clock. 

Depending on how old your generator is, you might need to shut it down every eight to ten hours so that the engine can cool. An overheated engine is a great way to damage your generator or the engine that’s running it. If your generator engine doesn’t need to cool and the fuel level looks good, then the only reason to stop your generator is to change the oil or restore the main power grid. 

What Kind of Gas is Best to Power my Generator? 

When it comes to powering your generator, you will have three options for fuel: natural gas, propane gas, diesel fuel, or unleaded gasoline. Unleaded fuel is usually only applicable for portable generators, so the choice is usually between propane and natural gas. 

Natural gas is the best option for operating your generator, but natural gas isn’t always available where you live. In those cases, propane is the only form of useable fuel for your generator. Natural gas is best because it’s unlimited, and you don’t have to refill your tanks periodically. Natural gas also burns cleaner and more efficiently than the other two options. It’s usually the cheaper option as well. 

Final Thoughts

Whole house generators are great commodities as long as you choose the right one and take care of it. Like most things, if you take care of your generator, your generator will care for you. When the time comes to turn your generator off, use one of the above methods to ensure that you do it safely and effectively. 

It’s also crucial that you know when it’s necessary to turn your generator off. Suppose you need to refuel, allow the engine to cool down, perform maintenance or cleaning of your generator, or do electrical work. In that case, you should always turn your generator off for safety. Once again, use the above methods to safely terminate your generator’s power and ensure that it will start up again when needed. 


Hubert Miles

I've been conducting home inspections since 2002. I'm a licensed Home Inspector, Certified Master Inspector (CMI), and an FHA 203k Consultant. I started PickGenerators.com to help people better understand whole-house and portable generators.

Recent Posts