You may not know it, but there’s a lot of science behind air conditioning. The amount of tonnage your AC unit needs is based on several complex factors, including your area’s climate and humidity level. Today, we’re going to show you how to read the tonnage of your AC unit so that you can make sure it’s appropriately sized for your home.
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Here’s how to read tonnage of an AC unit:
- Look for the model number on your AC unit.
- Find the tonnage rating in the model number.
- Divide the rating by 12 to get the tonnage.
This article will give you a quick and easy guide on finding the tonnage of your AC unit. By following these simple steps, you can be sure that your AC is the correct size for your home.
1. Look for the Model Number on Your AC Unit

The first step is to find the model number on your AC unit. This can usually be found on the side or back of the unit. It is often printed in small letters and may be difficult to find.
Take this as an example:
Model number: TCJD24S41S3A
The first two digits (24) represent the tonnage of this unit – those are the numbers we are interested in. The rest depict the make, model, and year of the unit.
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2. Find the Tonnage Rating in the Model Number
The next step is to find the tonnage rating in the model number. The number will be divisible by 12, and it will be followed by a letter.
12 represents 12,000 BTUs per hour, the standard measurement for air conditioners. So, if you divide the tonnage rating by 12, you’ll be able to find out how many BTUs per hour your AC unit can produce. This information is important because it will help you determine the size of the AC unit you need.
In our example, the tonnage rating is 24, but it can be anywhere between 18 and 60.
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3. Divide the Rating by 12 to Get the Tonnage
The final step is to divide the rating by 12. This will give you the approximate size of your AC unit in tons.
We would divide 24 by 12 to get 2 tons in our example.
Now that you know how to read the tonnage of your AC unit, you can now get an appropriate replacement for your home.
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Why Is Tonnage Important To Know?
Tonnage is important to know because it will help you determine the cooling capacity of your AC unit. The cooling capacity is the amount of heat your AC unit can remove from a room in an hour.
It’s important to have an AC unit with the right tonnage for your home. If it’s too small, it won’t be able to keep your home cool and comfortable. It will also use more energy than necessary to cool your home if it is too big.
Tonnage information should help you choose the right sized air conditioner for your home but always consult with a professional before making your final decision.

How Much AC Tonnage Do You Need?
The tonnage you need will depend on many factors, including the climate and the size of your home. You will need about 1 ton of AC for every 600 sq ft (55.74 sq m) of living space. So, if you have a 2,000 sq ft (185.80 sq m) home, you will need a 3-ton AC unit.
If you live in an area with a hot climate, you will need a larger AC unit to cool your home. For example, if you live in Arizona, you will need about 1.5 times more tonnage than someone in Wisconsin.
It’s important to choose an AC unit with the right tonnage for your home. If you’re unsure which size to choose, you can always ask a professional for help.
My home in Arizona is 2,000 sq ft (185.80 sq ft). According to the formula, I would need a 3-ton AC unit. However, I use a 4.5-ton AC unit to keep my home cool and comfortable because I live in a hot climate.
The most important thing is to make sure that your AC unit is the appropriate size for your home. By following these simple steps, you can be sure that your AC unit will keep you cool all summer long.
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How Many Kilowatts Does a 3-Ton AC Unit Use?
The kilowatts usage of a 3-ton AC unit will vary depending on the model and brand. However, a 3-ton AC unit will generally use about 3500 watts per hour. So, if you use your AC unit for 10 hours per day, it will go through about 35 kilowatts per day.
My unit uses about 30 to 40 kilowatts per day, so my monthly electricity bill is about $100.
The bottom line is that a 3-ton AC unit will use about 3500 watts per hour. However, the actual usage will vary depending on the model and brand. If you’re concerned about how much your AC unit will cost to operate, you can check with the manufacturer.
How To Tell if Your AC Unit Is Oversized?
If your AC unit is too big for your home, it will cycle on and off more frequently. This is because the AC unit will reach the desired temperature quickly, but it will cool the room so fast that it will turn off before getting rid of all the humidity.
One of my neighbors has a 5-ton AC unit for their 2,500 sq ft (232.25 sq m) home. As a result, their AC unit cycles on and off frequently, and their home feels stuffy and humid.
This is not ideal because their AC unit is not working efficiently. If your unit is too big for your home, you can ask a professional to help you choose a smaller unit.
You might also want to consider a zoning system, which will allow you to control the temperature in different areas of your home. This can be a great way to ensure that your AC unit is sized correctly for your home.

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What Are the Benefits of a Smaller AC Unit?
There are several benefits to choosing a smaller AC unit for your home:
- Save money: A smaller AC unit will use less energy, saving you money on your monthly electricity bill.
- Low noise levels: Smaller AC units tend to have lower noise levels than larger units.
- Longer lifespan: Smaller AC units typically have a longer lifespan than larger units.
- Ease of installation: Smaller AC units are often easier to install than larger units.
- No restrictions: Some jurisdictions have restrictions on the size of AC units installed. A smaller AC will not be subject to these restrictions.
- Pleasant look: Smaller AC units are more aesthetically pleasing than larger units.
Will a Smaller AC Unit Work As Well as a Larger Unit?
A smaller AC unit will not cool your home as quickly as a larger unit. However, it will still be able to cool your home effectively. The most important thing is to make sure that your AC unit is properly sized for your home.
The last thing you’d want is an AC unit that’s too small for your home. This will cause your unit to work harder, using more energy and shortening the unit’s lifespan.
I had this issue growing up. My parents had a 1.5-ton AC unit for our 2,000 sq ft (185.80 sq ft) home. As a result, the AC unit worked overtime to cool the house, and it only lasted for about five years before it needed to be replaced.
When the replacement time came around, they chose a 3-ton unit, which worked much better and lasted for over 10 years.
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Final Thoughts
Choosing the correct size AC unit for your home is important, but it can be tricky to figure out which size is best. If you’re unsure which size to choose, you can always ask a professional for help.
If you feel brave, you can try to figure out the size yourself. To do this, you’ll need to know the square footage of your home and the climate in your area.
Once you have this information, you can use one of the many AC sizing calculators available online. They can tell you which size AC unit is best for your home.