10 common mistakes people make with home generators

Following the right steps for home generator use and maintenance helps make sure there is safe, reliable, and consistent power for the long haul.
Two elderly people looking at a large grey generator in the woods
Most home generators still run on natural gas, which makes refueling a delicate chore. Juana Arias for the Washington Post/Getty Images

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This article was originally featured on BobVila.

After experiencing a long power outage at home, the importance of ensuring that power is consistent and reliable can become a priority. For those who live in an area that regularly experiences storms and inclement weather, they may be part of the almost one-fifth of US single-family households that have a home generator.

Proper maintenance of a generator is crucial to achieve the peace of mind that it will work during the next power outage, but the thing about home generators is that winging it isn’t an option. Knowing how to maintain and operate a generator can’t be learned on the fly, as it’s too easy to make mistakes that can damage the unit or put one’s safety in jeopardy. Without a careful approach, the results can be some pretty common mistakes when it comes to the machine’s operation and maintenance.

Using the wrong extension cord

To maintain safety and avoid a power crisis in the dark, check out these tips to keep a home generator ready for whenever it’s needed.

Most generators need an outdoor grounded extension cord with GFCI functionality of at least 14-gauge. Without this, electricity could flow where it shouldn’t and result in danger like fire or electrocution. Keep in mind that old cords might be unsafe, and the cord’s length and load’s amperage also will play a key part in what the cord can actually handle. The best rule of thumb to safely operate your generator without blowing a fuse, getting electrocuted, or causing a fire? Always check the user manual.

Running the generator in enclosed spaces

Starting a generator from the garage or anywhere near the house isn’t advisable because the exhaust contains deadly carbon monoxide. The ideal spot to use a generator is outside in a dry area (to keep moisture out), far from open doors and windows. At least 25 feet is usually safe. Give the machine at least 5 feet of clearance around its entirety, too.

If you’re using a portable generator that might be stored in the garage, never tempt fate by starting it in there. Also, a stationary generator should be installed by professionals in a suitable location.

Using poor quality fuel

It might be tempting to save a few bucks with cheap fuel instead of premium, but doing so can damage the unit and end up costing much more in the long run. Issues like clogged injectors from substandard gas can promote microorganism growth and reduce a generator’s output.

If a generator has been sitting idle for a few months, the old gas could go bad. To avoid this, be sure to run the machine regularly, drain the gas before using a stored generator, or add a fuel stabilizer for freshness.

Powering on and off incorrectly

Most generators follow similar basic steps to safely power on and off a generator. Before powering a generator on, plug in extension cords. Then add any loads into the extension cord. To turn off the generator, unplug the loads from the cord and then unplug the cord from the generator. When all cords are unplugged, turn off the generator. 

For safety, be sure to check the user manual so the generator is turned on and off properly to help avoid damage or strain on the unit.

Connecting to a service panel

Connecting a generator directly to the service panel of a home, or back feed, can end up creating a very hazardous risk of electrical fire. When the power kicks on again, it’s possible for residual energy to travel up the line backwards. Not only could this illegal practice put yourself in danger, but neighbors and any utility workers could potentially be harmed by the high voltage, too.

Instead, it’s best to have a licensed electrician install a manual transfer switch to any portable generator. This switch changes the source of power for the home, between the grid and the generator.

Fueling up while operating

It’s important to wait until the generator is cool before adding fuel. Adding gas while the generator’s motor is running, or even if it’s off but still hot, may result in a fire and explosion. Also, avoid topping off the gas in a generator when its tank is empty. Fires can instantly start from just a small splash of fuel landing near the spark plug or on the hot exhaust. So, always ensure the generator is turned off and has had a chance to cool down before fueling it up.

Running the generator in the elements

Never run a generator in wet weather to avoid damaging the inverter or getting electrocuted. The risks occur when water makes its way into outlets or electrical panels, resulting in the frame short circuiting. Generators should be used on level ground in a dry, open area, or under a generator cover (even though they technically work in rain, snow, or sleet).

Neglecting routine maintenance

Regular and routine maintenance tasks come with generator ownership, as they’re pretty complex pieces of equipment. Over time, not following manufacturer’s recommendations or addressing small issues could mean problems. At best, there may be problems with starting or seizing up, and at worst, there could be total failure of the unit.

Part of regular maintenance includes checking and cleaning the oil and air filter, inspecting the batteries, and running the generator at least monthly. Generators need to be run more often in colder seasons.

Hiring a subpar technician

When it comes to the maintenance and repair of a home generator, they sometimes require technical capabilities. At some point in its lifetime, you’ll likely need a specific skill set and advanced knowledge to install, repair, or maintain the machine. That’s when a qualified technician is helpful.

It’s smart to properly vet a technician’s expertise and experience by reading about them, checking if they’re Electric Generating Systems Association-certified, asking them questions, and checking their references.

Keeping poor or no records

It’s prudent to really understand how to use, service, and maintain a home generator, and to know what the unit can do for a home. This includes the quantity of fuel it needs, how the power will be used, and when it runs. Knowing and keeping track of these things will help ensure a consistent amount of gas and generator capacity at all times. If minimal notes are being kept—or even worse, none at all—it could easily result in wasted fuel or other expensive errors.