What Size Generator To Run 3 Ton AC Unit?
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Are you looking for the best size generator to power your 3-ton AC unit? You’re in the right place!
In this blog post, we’ll discuss the various sizes of generators available and the power requirements of your 3-ton AC unit.
We’ll also cover the safety considerations and tips for choosing the right generator for your home.
What Size Generator To Run 3 Ton AC Unit?
When it comes to keeping your house cool during the summer months. One of the most important considerations is the size of the air conditioner unit.

The general rule of thumb is that you need a generator that can produce at least 14000 watts or 14 kW of power to run a 3-ton AC unit.
So, if you’re looking for a generator, make sure that it’s rated for at least 14 kW of power.
Follow the below table as a guideline to determine what size generator you need:
Generator Watts | Central AC Size |
---|---|
6,000 Watts | 1.5 ton |
8,000 Watts | 2 ton |
12,000 Watts | 3 ton |
15,000 Watts | 4 ton |
18000 Watts | 5 ton |
What Factors To Consider To Choosing A Generator?

Of course, there are other factors to consider when choosing a generator. In addition, below is the list of some critical factors:
1. The first factor is the starting wattage. Starting wattage is the amount of power needed to start up your air conditioner.
It’s generally about 2-3 times the running wattage. So, if you have a 3-ton AC unit, you’ll need a generator that can produce at least 28000 watts or 28 kW of power to start it up.
2. Running wattage is the amount of power needed to keep your air conditioner running.
For a 3-ton AC unit, you’ll need a generator that can produce at least 14000 watts or 14 kW of power.
3. Surge wattage is the extra power needed to start up your air conditioner. It’s generally about 2-3 times the running wattage.
So, if you have a 3-ton AC unit, you’ll need a generator that can produce at least 28000 watts or 28 kW of power to start it up.
4. There are two types of generators: gas and diesel. Gas generators are less expensive, but they’re also less powerful.
Diesel generators are more expensive, but they’re also more powerful. You’ll need a diesel generator if you have a 3-ton AC unit.
5. Some generators are very noisy, while others are pretty quiet. If you have a 3-ton AC unit, you’ll need a generator rated for at least 65 dB of noise.
6. Run time is the amount of time your generator can run before it needs to be refueled.
For a 3-ton AC unit, you’ll need a generator that can run for at least 8 hours on a full tank of gas or diesel.
7. Warranties vary from manufacturer to manufacturer and from model to model. Make sure to read the fine print carefully before you purchase a generator.
8. Generators can range in price from a few hundred dollars to several thousand dollars.
If you have a 3-ton AC unit, you’ll need a generator that’s priced at least $2000.
As you can see, there are a lot of factors to consider when purchasing a generator. Be sure to do your research and buy the one that’s right for you and your needs.
What Size Generator To Run 2.5 Ton AC Unit? (Top Brand Pick)
How To Size Your Backup Generator

There are a few different ways to size your backup generator. The most common way is to use a watts/kilowatts (kW) calculator.
Follow the below steps to size your backup generator:
Step 1: Calculate The Wattage Of The Appliances
First, you need to know the wattage of the appliances and devices you want to run.
The wattage rating can be found on the appliance or device, in the owner’s handbook, or on the label. Also you can use this Watts/Amps Chart if you can’t find it.
Step 2: Find The Wattage
Next, you need to add the wattage of all the appliances and devices you want to run.
For example, if you have a fridge rated for 1000 watts and a TV rated for 200 watts, your total wattage would be 1200 watts.
Step 3: Calculate The Surge Wattage
Now, you need to multiply your total wattage by 1.5 to get your surge wattage.
Surge wattage is the extra power required to start your appliances and devices. In our example, 1200 watts x 1.5 = 1800 watts of surge wattage.
Step 4: Final Calculation
Finally, you need to add your running wattage to your surge wattage. In our example, 1800 watts + 1200 watts = 3000 watts.
This is the minimum wattage you’ll need for your backup generator.
Although four steps may not seem like much, they are crucial in determining the size of your home backup generator.
Without proper care, you could create an inaccurately sized generator by failing to account for voltage levels.
Why Is It Essential To Purchase The Correct Size Generator?

Purchasing the correct size generator for your home backup is essential because an undersized generator will not be able to power all of your appliances and devices, and a large generator will be a waste of money.
The most significant advantage of having the right-sized generator is that it will run more efficiently.
A little generator will have to work harder to power your appliances and devices. But an oversized generator will use more fuel than necessary.
Another advantage of having the right-sized generator is that it will be less likely to overload and shut down.
When a generator is overloaded, it can damage the electrical components and cause a fire.
Finally, an accurately sized generator will last longer than one that’s too small or too large.
This is because an undersized generator will have to work harder, and an oversized generator will run less often.
So, now that you know how to size your backup generator and why it’s essential to get the correct size, let’s take a look at some of the best-sized generators on the market.
FAQs
How Much Power Does A 3-Ton Air Conditioner Use In Starts Up?
A 3-ton air conditioner uses approximately 3500 watts of power. It is essential to have a generator that can provide at least this much power.
Keep in mind that you will also need to account for the surge wattage. Which is typically 1.5 times the running wattage.
How Much Electricity Does A 7500-Watt Generator Use?
A 7500-watt generator can power a water heater, fan heater, microwave, fridge (or freezer), washing machine, TV, and five 75 watt light bulbs simultaneously.
However, ensuring that the generator can provide enough power for your specific needs is essential.
Can I Run AC With A 7500 Watt Generator?
Yes, a 7500-watt generator can power a 3-ton air conditioner. Besides the air conditioner, you can also run other appliances and devices simultaneously.
So, if you want to run an air conditioner and other instruments, ensure the generator can provide at least 3500 watts.
Final Thoughts
Size is an essential factor when purchasing a backup generator for your home. Be sure to use a watts/kilowatts calculator to size your generator correctly.
Remember, it’s better to err on caution and get a generator that’s too large than one that’s too small.
After reading this, you should better understand how to size your backup generator.