Last Updated on April 25, 2023 by Rod Olivares
Can a portable generator power your Central AC unit? YES.
But you will likely need a larger watt portable generator (10,000 watts or higher). A little, quiet 2,000 watt generator is not going to cut it to run most central AC units. Portable generators are great for powering small appliances and tools, like those used for tailgating or camping.
And that’s all they’re suitable for, right? Wrong! A portable generator can be an excellent option for providing backup power to your house in the case of an emergency power loss.
You may not be able to power everything in your home, depending on your portable generator’s capacity, but you should be able to power the most important things.
In warm weather, one of the essential items to power is your air conditioner. Can your portable generator power your central air conditioner? Read on to find out what size generator you need to run your air conditioner.
How many watts does central AC use?
To understand whether your portable generator can power your central air conditioner, you first must know the required wattage.
You’ll also need to know both the starting wattage and running wattage capacity of your generator.
If the AC’s wattage is within the boundaries of the generator’s wattage, you should be able to safely power your central AC.
For example, let’s say that your AC needs 6,700 starting watts and 6,000 running watts, while your generator offers 9,375 starting watts and 7,500 running watts. Your generator would be able to power your AC because the wattage required is within the bounds of the wattage available.
However, consider whether you need to power anything else concurrently. In this example, you still have 2,675 excess watts. That may be enough to power a few other things, like an energy-efficient refrigerator and powering up a sump pump.
It probably won’t be enough to power everything in your home, though. See my whole house generator sizing calculator for powering your whole house.
Starting watts vs running watts
When trying to decide if your central AC and your portable generator are a perfect match, the most significant number is starting wattage.
Most central ACs need a pretty significant wattage for starting up, sometimes 1,000 watts over the running watts needed.
Your generator must be able to handle the starting wattage.
If you’re not sure what wattage your AC requires, look at the unit’s nameplate or check with the manufacturer.
It’s of paramount importance that you never guess or assume what the wattage is. If you try to power something that has a more significant need than your generator can handle, you’ll risk overloading it and potentially causing severe damage to anything plugged into the portable generator.
Worst case scenario, an overloaded generator could even result in a fire.
Make sure you know that your generator can handle it before attempting to power your central air.
Average central air conditioning wattage?
You’ll see an extensive range of wattage for central AC units.
Energy-efficient units, even large ones, may need as little as 2,000 watts while large, older units with less efficiency may require up to 10,000 watts.
There’s no one answer here. It doesn’t matter how many watts your friend’s air conditioner uses or how many watts the internet tells you is the average.
The only numbers that matter is the exact numbers for your specific unit.
Take the time to get this right, or you could end up seriously regretting it.
Which portable generators are powerful enough to power AC?
For most central AC units, you’ll need a generator with quite a bit of power.
Especially true if you want to power more than just the AC unit. Here are four good options from highest to lowest watts.
1. Best 15,000 Watt Generator for Central AC: DuroMax XP15000E 15000-Watt
When you need 15,000 watts, you need 15,000 watts. DuroMax XP15000E beast of a portable generator really pushes the limits of “portable.” It does have wheels, which you will need as you are not going to pick up this 340lb monster. But this beast will power nearly any size central AC unit. When you need power, sometimes you go big. The DuroMax XP line does have other good watt sizes as well, such as a little “less heavy 10K model.
2. Best 8,000 Watt Generator for Central Air Conditioning: Pulsar PG10000B 8000-Watt Dual Fuel Portable Generator
Pulsar PG10000B generator is a bit pricey, but it offers more power. With 10,000 starting watts and 8,000 running watts, it’s prepared to handle even really large central AC units.
In many cases, this capacity means that you will be able to power the entire home.
You should, for sure, have enough power to run several major home appliances at once.
It has an electric push-button start, and it’s entirely RV-ready if you sometimes want to take it on the road.
You’ll be able to use it power a window AC in your RV if desired.
You get as much power with this portable as you get in many stationery, standby home generators–but with all the conveniences of a portable.
3. Best Dual Fuel Generator for AC: Champion 7500-Watt Dual Fuel Portable Generator with Electric Start
Just like our hypothetical example earlier, this generator offers 9,375 starting watts and 7,500 running watts. That’s enough power to handle most central AC units.
It’s a dual fuel unit that runs on either gasoline or propane and has a convenient electric start.
It has a volt guard, so you’ll be safe charging your cell phone or laptop when you’re running your AC without risk of damage to these sensitive electronics.
Champion 7500-Watt Dual Fuel Generator has a gauge to help you monitor the power output to make sure you’re not pushing it beyond its limits.
For its size and capacity, this generator is also remarkably quiet at only 74 dBA.
4. Best Smaller Generator for small central AC units: Briggs & Stratton 30545 P3000 PowerSmart Series Portable 3000-Watt Inverter Generator
This generator is a bit more affordable, but that comes with less power. With 3,000 starting watts and 2,600 running watts, it probably doesn’t have enough juice to power a central AC unit for a considerable home.
That said, it should have enough to power a smaller central AC system.
Designed to be fully portable, this generator comes with wheels and carry handles so you can bring it along for camping and tailgating when not using it at home for backup power.
This RV-ready unit has enough power to start up most window AC units for RVs.
A little display screen keeps you apprised of the power output and other relevant stats.
This unit is parallel-ready, so if you buy two of them, you can hook them together and double your power.
Depending on the wattage needs of your air conditioner, you’ll also be able to charge your cell phone simultaneously with the convenient USB port.
Powering a window unit air conditioner?
Typically, a window unit air conditioner will take less power than a central AC unit.
The math, though, is the same.
You need to find out both the starting and running wattage the air conditioner needs and check to make sure that fits within your generator’s capabilities.
For example, let’s say your window AC needs 2,000 starting watts and 1,500 running watts, and your Yamaha EF2000iSv2 generator offers 2,000 starting watts and 1,600 running watts.
That’s just enough power for you to run your window AC unit.
You won’t be able to power much else in the home, but your window AC should work just fine.
If you instead used the Champion 3400-Watt Dual Fuel generator with its 3,400 starting watts and 3,100 running watts, you would have enough power to run your window AC as well as a few other things.
The numbers in that example were on the high side for window AC units. Many smaller window air conditioners only need 500-700 running watts.
Even the smallest capacity generators should be able to handle the AC’s load.
Even the Sportsman 1000-Watt Inverter Generator with its 1,000 starting watts and 800 running watts would be up to the job with a little room to spare to power something else.
Regardless of the size of your AC unit, it’s vital that you know the actual numbers and don’t just guess or assume.
You can generally find the necessary wattage for your AC in the manual, on the unit’s nameplate, or by searching the model number online.
Don’t rely on estimated or average numbers. Find out the exact number, or you may regret it.
Will A 6,500 Watt Generator Run Central Air?
A 6500-watt generator is going to be a little larger than most will opt for when it comes to residential use.
However, for those who are wanting to run a central air conditioning unit during the summer, a blackout, or simply for recreational use, a 6500-watt generator can run most average-sized central air conditioners.
What you will want to do in this situation is to find out how many watts your central air conditioner is going to need.
This information can be found either on the A/C unit itself or look up the specs by the model number online.
Compare this with several 6500-watt generators to see if the generator is going to offer sufficient wattage for your air conditioner.
When you lose power during hot weather, the two top priorities for most people are running the refrigerator and the air conditioner. Whether you have a central AC or a window AC unit, you should be able to power them with your portable generator.
However, you must make sure of this before trying it.
You need to know both the starting and running watts the air conditioner requires. Make sure those numbers fit within the generator’s starting and running wattage capacity.
When you want to run more than just the AC, you’ll need to also add in the starting and running watts of whatever else you want to power.
Let me know in the comments if you have any questions about powering an AC unit with a portable generator!
Scott Krager purchased generatorgrid.com in the summer of 2020 and quickly began to buy every generator under the sun! He currently has over a dozen generators and the number is growing quickly. He lives in Portland, OR near his family and friends.
GeneratorGrid.com is an independent review business. I am not affiliated with any manufacturers and do not accept paid reviews. When you buy through my links, I may earn a commission which helps me purchase more generators for testing. - Scott Krager