What Size Generator To Run 2.5 Ton AC Unit? (Top Brand Pick)
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This comes as no surprise that there are several types of generators, and not all of them will allow you to power your air conditioner.
This should be your primary consideration when purchasing a generator for an air conditioner that is the appropriate size for a 2.5-ton air conditioner.
What Size Generator Do I Need To Run 2.5 Ton AC Unit?
To run a 2-5 ton AC unit, you’ll need a generator with a power output of between 7.5 and 20 kW. These generators will support the efficient running of your air conditioner as well as allow you to operate other appliances.
Follow the chart for the generator sizes of 2.5 Ton AC.
Capacity | Sizes | Recommended Brands |
---|---|---|
Minimum | 7.5 kW | DuroMax Gas or Propane Powered Generator |
Average | 10 kW | Champion Power Equipment Generator |
Maximum | 20 kW | Westinghouse Home Backup Portable Generator |
How To Choose A Generator To Run An 2.5 Ton Air Conditioner?

Consider the following factors when purchasing a generator to power a 2.5-ton air conditioner:
Fuel
The fuel is the most critical component that allows the generator to work effectively, and you intend to use it to power your air conditioner.
You’ll need a generator with a large fuel tank or one with two tanks added for this.
You’ll need to use a lot of gasoline to run the air conditioner, so be sure you have enough storage.
Installation
You should get an aircon generator that your house electrician can easily install.
Your home electrician would be familiar with your wiring and would find it simple to install the generator.
Otherwise, repairing the generator would be tough, and you would have to pay a hefty price to hire a skilled electrician.
Automatic Transfer Switch

If you need to purchase a standby generator, you won’t have to worry about the transfer switch.
If you want to get the greatest generator for operating your air conditioner, you should get a transfer switch with it instead of extension cables.
There are other advantages, such as not having to manually turn on the generator after a power loss because the transfer switch does it automatically.
Efficient Operation
Generators allow you to keep up with your priorities even when the power goes out.
After a power loss, your air conditioner can still operate, thanks to a module known as AC power control modules, which monitors the load on your house’s circuits and immediately shuts down the circuits with lower priority.
What Type Generator Do I Need To Run A 2.5 Ton AC?
We can recommend you to use the following 2 types of generator for a 2.5 ton AC.
Portable Generator

There is an option to run a 2.5 ton AC unit is to have a portable generator installed and wired directly to your electrical panel.
Using a large electrical portable generator will eliminate the need for someone to be present to start and connect it to the main breaker panel when the power goes down.
Whole House Generator
Many whole-house generators are intended to start and switch over in under a minute after the main power is turned off.
Because whole-house generators are frequently powered by propane or natural gas, there’s no need to stock up on gasoline cans or worry about the generator shutting down due to a lack of fuel.
How To Keep A Generator Safe To Run A 2.5 Ton AC?
We suggest you some safety tips to run your 2.5 AC unit.
- Throughout a power outage, placing a generator transfer switch at your meter base will protect you from harmful electrical back-feeding onto electrical lines.
- Grounding the generator is suggested to assist prevent unintentional electrical shock. Always start the largest electric device first, then plug in other goods one at a time.
- Choose an extension cable that is appropriate for the instrument or appliance. When using an appliance or equipment that is located far away from the generator, larger gauge three-wire/three-prong cables should be utilized.
- Keep the generator dry and avoid using it in damp or rainy weather. Operate it in a dry area beneath an open, canopy-like structure to keep it dry. Before contacting the generator, dry your hands if they are moist.
- Never attempt to power the home wiring by hooking the generator into a wall socket, which is known as “back feeding.” This is a very unsafe technique.
- In the event of a power outage, stationary generators that are permanently placed are better equipped to provide backup power to the home. Even if a portable generator is correctly connected, it might get overloaded which results in a generator failure.
Best Generator To Run 2.5 Ton AC Unit
1. DuroMax XP12000EH Generator 12000 Watt Gas or Propane Powered Home Back Up
- Powerful DuroMax Engine: the XP12000EH is powered by a DuroMax, 457cc OHV engine.
- Dual fuel technology: the ability to run on propane or gasoline allows the freedom and flexibility of fuel choice. Protects your investment by automatically shutting the generator off when it senses that the oil is low
- Plenty of power: with 12,000 starting watts and 9, 500 running watts, This unit can handle heavy loads from lights and a refrigerator to a home air conditioner and high amperage power tools.
- Maximum power: with DuroMax MX2 technology, get the maximum power from each of the 120 volt receptacle. Choose between operating the generator at both 120 V and 240 V Simultaneously, or at 120 only with full power.
- Powering everyone anywhere: like all DuroMax generators, the XP12000EH is EPA and CARB approved For use in all 50 States.
- Engine Type: 4-Stroke
2. Champion Power Equipment 15,000/12,000-Watt Portable Generator
- Ultra-Powerful – At 15,000 starting watts and 12,000 running watts, enjoy up to 9 hours of run time on a full tank of gasoline with a noise level of 78 dBA from 23 feet
- Electric Start – Trust the reliable 717cc V-Twin Champion engine with its battery-included electric start featuring a reliable toggle switch, plus built-in Cold Start Technology for easy starts in cold weather
- Covered Outlets – One 120V 30A locking, a 120/240V 30A locking, a 120/240V 50A and four 120V 20A GFCI outlets, plus Volt Guard built-in surge protector prevents overloads and keeps your appliances and equipment safe
- Lift Hook – Designed for safe and easy transport, loading and unloading, plus the Intelligauge keeps track of voltage, hertz and run-time hours so you can easily monitor power output and track maintenance intervals
- Champion Support – includes 3-year limited warranty with FREE lifetime technical support from dedicated experts
3. Westinghouse WGen20000 Home Backup Portable Generator
- 20,000 Running Watts and 28,000 Peak Watts; Easy-Access Start Panel with Keyed Electric Start, Choke Knob, and Fuel Control Valve; Up to 17 Hours of Run Time at 25% load on a 17 Gallon Fuel Tank With Fuel Gauge
- Featuring Four GFCI 120V 5–20R Standard Household Outlets, Two 50A 120/240V 14-50R Outlets, Two 30A 120/240V L14-30R Outlets, and One 30A 120V L5-30R Outlet; All Outlets Have Rubber Covers for Added Safety
- Powered by a Heavy Duty 999cc Westinghouse V-Twin OHV Engine Featuring a Cast Iron Sleeve, Reinforced Steel Handles with Quick-Release Pins, Automatic Low Oil Shutdown, Idle Control, and Digital Readout Displaying Lifetime Run Hours, Volts, and Frequency.
- Plug-and-Play: Oil, Funnel, Setup Guide, and Manual to Get You Started Right Out of the Box
- All Westinghouse Portable Generators are Functionally Tested in the Factory and May Contain Minimum Residual Oil and/or Fuel Odor; EPA Compliant; Backed by 3-Year Limited Service, Labor, and Parts Coverage with Nationwide Customer Service Network
FAQs About The Right Size Generator To Run An 2.5 Ton AC Unit
1. How Can I Figure Out How Many Watts Do I Need To Run A 2.5 Ton AC Unit?
Ans: It’s important to know how many watts your air conditioner requires so that you can choose the finest generator for the job. LRA refers to the maximum current necessary to start the engine.
If you want assistance, you may use an LRA calculator. After you’ve received your LRA, you can start looking for the right size generator to power your air conditioner.
2. Will Generators Cause Damage To Electronic Devices When Running A 2.5 AC?
Ans: Many portable generators aren’t completely safe to operate around sensitive gadgets like televisions and PCs.
When the generator runs out of gas and stutters, the power might be unequal, and surges and voltage swings can destroy delicate circuits.
3. What Happens If My Generator Is Overloaded While Running A 2.5 Ton AC?
Ans: Portable generators should never be overloaded, yet for a short time, all portable generators may generate double their typical power.
When a generator is run for lengthy periods of time with an overload, several things might happen, such as overheating. burn out windings. low oil pressure, engine failure, and a little lifespan of the generator.
The Bottom Lines
When purchasing a generator for a 2.5 ton AC unit, there are numerous factors to consider.
It’s critical to make the best options possible based on these considerations if you want to get the most out of your generator.