What Size Generator Needed to Run Your AC
- Types of Air Conditioning
- What Size Generator is Needed to Run Your AC
- Generator Size for Mini-split AC
- Generator Size for Window Air Conditioner
- Generator Size Portable AC Unit
- Generator Size for Ducted Individual AC
- Generator Size for Ducted Central AC
- Generator Size for Ceiling Suspended AC
- Generator Size for Cassette AC
- Generator Size for Floor Standing AC
- Generator Size for Packaged AC Unit
- Generator Size for Packaged RTU AC
- FAQs
- Final Words
When the heat hits, nothing feels better than a cool room with your AC running. But what happens when the power goes out or you're in a place without electricity? A generator can help, but how do you know what size to get? The right generator size makes a big difference. This guide will help you figure out what size generator is needed to run your AC.
Types of Air Conditioning
There are many types of air conditioners. Each type requires a different generator size based on the cooling power (measured in BTUs). Below is a breakdown of common air conditioners, their characteristics, and power requirements:
AC Type | Typical Capacity | Air Supply | Mounting | Typical Application | Description |
Mini-split AC | Small to large | Direct | Wall | Residential | Efficient for small areas or individual rooms, quiet and compact. |
Window Air Conditioner | Very small to small | Direct | Window | Residential | Compact and designed to fit into a window, great for cooling one room. |
Portable AC Unit | Very small to small | Direct / Ducted | Floor | Residential, remote areas | Freestanding, portable units, ideal for moving between rooms. |
Ducted Individual AC | Small to very large | Ducted | Ceiling | Residential, commercial | Uses ducts to cool individual rooms, ideal for multiple rooms. |
Ducted Central AC | Medium to very large | Ducted | Ceiling | Residential, commercial | A larger system used to cool the entire house, usually via a central duct system. |
Ceiling Suspended AC | Medium to large | Direct | Ceiling | Commercial | Installed on the ceiling, used primarily in commercial spaces. |
Cassette AC | Medium to large | Direct / Ducted | Ceiling | Commercial | Ceiling-mounted unit that efficiently cools commercial spaces. |
Floor Standing AC | Medium to large | Direct / Ducted | Floor | Commercial | Freestanding units, ideal for larger rooms or office spaces. |
Packaged AC Unit | Very large | Direct / Ducted | Floor | Commercial | Self-contained system that handles both cooling and heating. |
Packaged RTU AC | Very large | Ducted | Rooftop | Commercial | Rooftop units that cool large commercial buildings. |
What Size Generator is Needed to Run Your AC
To run your air conditioner with a generator, you need to match the size of your generator to the power needs of your AC. Air conditioners are rated by BTU (British Thermal Units), which tells you how much cooling the unit provides. A higher BTU means the AC uses more power. Let's take a look at the generator sizes for each type of air conditioner.
Generator Size for Mini-split AC
For a 6,000 BTU Mini-split AC, a generator with 1,000 to 1,500 watts is required.
A 9,000 BTU
Mini-split ACwill need a generator size of 1,500 to 2,000watts.A 12,000 BTU Mini-split AC needs a generator of about 2,000 to 2,500 watts.
A 15,000 BTU Mini-split AC requires a generator of 2,500 to 3,000 watts.
To power an 18,000 BTU Mini-split AC, you'll need a generator sized at 3,000 to 3,500 watts.
For a 24,000 BTU Mini-split AC, consider a generator with 3,500 to 4,500 watts.
A 30,000 BTU Mini-split AC will need a generator of 4,500 to 5,000 watts.
Running a 36,000 BTU Mini-split AC needs a generator around 5,000 to 6,000 watts.
A 48,000 BTU Mini-split AC requires a generator of at least 6,500 watts.
Generator Size for Window Air Conditioner
- To run a 5,000 BTU Window Air Conditioner, choose a generator with 1,000 to 1,500 watts.
- For a 6,000 BTU Window Air Conditioner, you’ll need a generator of about 1,500 watts.
- An 8,000 BTU Window Air Conditioner works with a generator of 1,500 to 2,000 watts.
- A 10,000 BTU Window Air Conditioner will need a generator of around 2,000 watts.
- A 12,000 BTU Window Air Conditioner requires a generator of 2,500 watts.
- To power a 14,000 BTU Window Air Conditioner, a generator of 3,000 watts is required.
- An 18,000 BTU Window Air Conditioner needs a generator with 3,500 watts.
- A 24,000 BTU Window Air Conditioner will need a generator of about 4,500 watts.
Generator Size Portable AC Unit
- An 8,000 BTU Portable AC Unit requires a generator of 1,500 watts.
- For a 10,000 BTU Portable AC Unit, a generator of 2,000 watts is enough.
- To run a 12,000 BTU Portable AC Unit, you need a generator of 2,500 watts.
- A 14,000 BTU Portable AC Unit will work with a generator of 3,000 watts.
- An 18,000 BTU Portable AC Unit requires a generator of 4,000 watts.
- To power a 24,000 BTU Portable AC Unit, you’ll need a generator of 5,000 watts.
- A 30,000 BTU Portable AC Unit will need a generator with 6,000 watts.
Generator Size for Ducted Individual AC
- A 12,000 BTU Ducted Individual AC works with a generator of 2,000 to 2,500 watts.
- To power a 15,000 BTU Ducted Individual AC, you need a generator of 2,500 to 3,000 watts.
- An 18,000 BTU Ducted Individual AC requires a generator of 3,000 watts.
- A 20,000 BTU Ducted Individual AC needs a generator with 3,500 watts.
- A 24,000 BTU Ducted Individual AC works with a generator of 4,000 watts.
- A 30,000 BTU Ducted Individual AC will need a generator of 5,000 watts.
Generator Size for Ducted Central AC
- A 2.5-ton (30,000 BTU) Ducted Central AC requires a generator of 4,000 watts.
- A 3-ton (36,000 BTU) Ducted Central AC works with a generator of 4,500 watts.
- A 4-ton (48,000 BTU) Ducted Central AC needs a generator of 5,500 watts.
- A 5-ton (60,000 BTU) Ducted Central AC requires a generator of 6,500 watts.
- For a 6-ton (72,000 BTU) Ducted Central AC, choose a generator with 7,500 watts.
- A 7-ton (84,000 BTU) Ducted Central AC works with a generator of 8,500 watts.
- An 8-ton (96,000 BTU) Ducted Central AC will need a generator of 10,000 watts.
Generator Size for Ceiling Suspended AC
- A 12,000 BTU Ceiling Suspended AC needs a generator of 2,500 watts.
- A 18,000 BTU Ceiling Suspended AC requires a generator of 3,000 watts.
- To run a 24,000 BTU Ceiling Suspended AC, a generator of 4,000 watts is needed.
- A 30,000 BTU Ceiling Suspended AC requires a generator of 5,000 watts.
- A 36,000 BTU Ceiling Suspended AC works with a generator of 6,000 watts.
Generator Size for Cassette AC
- A 12,000 BTU Cassette AC requires a generator of 2,500 watts.
- An 18,000 BTU Cassette AC will need a generator of 3,500 watts.
- For a 24,000 BTU Cassette AC, you will need a generator of 4,500 watts.
- A 30,000 BTU Cassette AC needs a generator of 5,500 watts.
- A 36,000 BTU Cassette AC requires a generator of 6,000 watts.
- A 48,000 BTU Cassette AC will need a generator of 7,000 watts.
Generator Size for Floor Standing AC
- A 12,000 BTU Floor Standing AC requires a generator of 2,500 watts.
- A 15,000 BTU Floor Standing AC needs a generator of 3,000 watts.
- A 18,000 BTU Floor Standing AC works with a generator of 3,500 watts.
- A 24,000 BTU Floor Standing AC requires a generator of 4,500 watts.
- A 30,000 BTU Floor Standing AC will need a generator of 5,500 watts.
- A 36,000 BTU Floor Standing AC requires a generator of 6,000 watts.
Generator Size for Packaged AC Unit
- A 12,000 BTU Packaged AC Unit needs a generator of 2,500 watts.
- A 18,000 BTU Packaged AC Unit requires a generator of 3,500 watts.
- For a 24,000 BTU Packaged AC Unit, you need a generator of 4,000 watts.
- A 30,000 BTU Packaged AC Unit works with a generator of 5,000 watts.
- A 36,000 BTU Packaged AC Unit requires a generator of 6,000 watts.
- A 48,000 BTU Packaged AC Unit needs a generator of 7,000 watts.
- A 60,000 BTU Packaged AC Unit requires a generator of 8,000 watts.
Generator Size for Packaged RTU AC
- A 30,000 BTU Packaged RTU AC requires a generator of 5,000 watts.
- A 36,000 BTU Packaged RTU AC needs a generator of 6,000 watts.
- A 60,000 BTU Packaged RTU AC will require a generator of 7,500 watts.
- A 100,000 BTU Packaged RTU AC needs a generator of 10,000 watts.
- A 150,000 BTU Packaged RTU AC will work with a generator of 12,500 watts.
- A 200,000 BTU Packaged RTU AC requires a generator of 15,000 watts.
- A 250,000 BTU Packaged RTU AC needs a generator of 17,500 watts.
FAQs
What is BTU and why is it important for my AC?
BTU stands for British Thermal Unit. It is a measure of the cooling (or heating) power of an air conditioner. The higher the BTU, the more cooling capacity the AC has. For example, a 5,000 BTU AC is suitable for small rooms, while a 24,000 BTU AC is better for larger spaces. Choosing the right BTU ensures your AC cools the room efficiently without wasting energy.
How do I know what size generator I need for my AC?
To find the right generator size, look at the BTU rating of your AC. The higher the BTU, the more power your AC needs. Choose a generator that can handle the starting surge and continuous running power. For example, a 12,000 BTU window AC needs about 2,500 watts.
When to Use a Portable AC Unit?
Portable air conditioners are ideal for temporary cooling when you're on the move or need flexible solutions for small spaces. They're perfect for scenarios like frequent power outages or cooling a small room without the need for a permanent installation. Because they are lightweight and compact, you can easily move them from room to room or even take them outdoors.
For example, the EcoFlow WAVE 3 Portable Air Conditioner pairs perfectly with the EcoFlow portable power station. This combination offers a powerful solution for cooling or heating your space in temporary setups, such as camping trips or emergency situations. The EcoFlow WAVE 3 provides 6100 BTU cooling and 6800 BTU heating, and when paired with a portable power station, it ensures that you stay comfortable no matter where you are. Whether you're cooling a tent during summer or heating up a chilly campsite, the EcoFlow WAVE 3's 8-hour wireless operation and fast temperature adjustments make it the ideal choice for on-the-go comfort.
Can I use a small generator for a large AC unit?
No, using a small generator for a large AC can cause the generator to overload. Larger AC units, like ducted central ACs, may require 5,000 watts or more, while small generators usually handle around 2,000 watts. Always match the generator’s capacity to your AC’s needs to avoid damage.
Does the type of AC affect the generator size?
Yes, different types of ACs need different generator sizes. For example, mini-split ACs are more energy-efficient and require smaller generators compared to ducted central ACs, which need larger generators to power the entire system. Check the BTU and type to select the right generator size.
What happens if I use a generator that’s too small for my AC?
If you use a generator that’s too small, the AC may not start or could shut down unexpectedly. A smaller generator can also overheat, leading to damage or a shorter lifespan. It's important to choose a generator that can handle both the startup and running power demands of your AC.
How long can a generator power my AC?
The runtime of your generator depends on its fuel capacity and the power consumption of your AC. A 2,000-watt generator can run a small window AC for about 5-6 hours, while larger generators (like 5,000-watt units) may run larger ACs for 8-10 hours. Always check the fuel efficiency and capacity for longer usage.
Final Words
Choosing the right generator size for your AC unit depends on the AC type and its BTU. Always pick a generator with a bit more power than the minimum to handle surges. Knowing your generator needs keeps you cool and prepared for anything, whether you're at home or outdoors.