How to Choose & Calculate AC Tonnage Capacity in India?

As a buyer, we Indians need to make sure that we are purchasing the right tonnage capacity of the air conditioner for our room. This simple decision can save our future electricity cost, and we can enjoy a perfect cooling experience for the next few years. This is the first step to select the AC for home.

An oversized ton AC consumes more electric power which results in high monthly bill.

What is Tonnage (Ton) Capacity in AC?

A ton represents the cooling capacity of an air conditioner. It denotes how much amount of heat an AC can remove from a room in 24 hours. We measure this amount of heat in BTU (British thermal unit). Usually, 1-ton AC removes 12,000 BTUs of heat in one hour. Likewise, 2 ton of AC removes 24,000 BTUs of heat from the same sized room. When all the heat is removed, you start feeling cold.

On the other hand, a 2 ton AC consumes more electric power as compared to 1 ton AC. It is because of 2 ton AC’s compressor requires more power to remove more heat from your room.

What is the Meaning of 1 Ton Capacity AC?

In layman’s term, 1 ton is equal to the heat required to melt one ton (907 Kg) of ice in 24 hours. As we know, 1 ton AC removes 12,000 BTU of heat in one hour; likewise, it removes 288,000 BTU (12,000 x 24) in 24 hours. Finally, we can understand that a 1 ton of AC removes 288,000 BTU of heat from a room in 24 hours. However, a large-sized room has more heat, and 1 ton AC is not sufficient enough for it. That is the reason we choose 2 ton or higher capacity AC for large rooms.

Check some of the best 1 ton capacity AC for you home.

Fun fact: There is a misconception that “ton” means the physical dimensional size of an AC unit, which is completely wrong.

How to Choose Right AC Tonnage Capacity?

We can easily choose the best possible tonnage capacity of our AC if we follow these four steps.

  1. Check the size of your room
  2. Check if your room is on the topmost floor
  3. Check if your room is exposed to direct sunlight
  4. If your room is directly in contact with the kitchen

(Step 1 of 4) Check the Size of Your Room

Based on room size, you can easily find out how much ton of AC you need. Generally, we have been told that 1-ton ac is enough for small room, 1.5 ton for a medium room and 2 ton for a large room. However, if you want precise capacity for your room, there is a simple formula to determine the perfect capacity you will ever need.

Ton Formula: If your room has a typical height of 10 feet then use this method. Check the length and breadth of your room carefully and follow this formula.

  • Suppose your room size is 12 feet wide and 15 feet long
  • So overall size is 12 x 15 = 180 Sq. Ft.
  • Now take the square root of 180 = 13.4
  • Finally, divide it by 10 = 1.34

So the approximate size you need for 12 x 15 feet room is 1.4-ton capacity AC. Using this formula, you can always determine the right capacity of AC you need. But wait, there are two more steps that might change the tonnage capacity you need.

(Step 2 of 4) Check if Your Room is on the Topmost Floor

If you live on the topmost floor, you need half (0.5 ton) more tonnage capacity on an AC unit. Why? Because in India, during extreme daylight, the surface of your room gets really hot, and your current capacity of AC may not supply enough cooling. That’s why, if your room’s surface is exposed to the sunlight, get 20% more cooling capacity.

Alternatively, if you live in an apartment or house with more than one floor and your room is located on the ground floor then leave this step and proceed to Step 3. if your area is generally not the hottest, you may also skip this step.

(Step 3 of 4) Check if Your Room is Exposed to Direct Sunlight

There is a very good chance that your room’s wall gets direct sunlight, especially from the West, South, or South-west direction. If that’s the case with you, consider buying half (0.5 ton) more tonnage capacity in your AC unit. Why? Because in India, we see sunlight coming from West, South, or South-west direction in the afternoon time. This is the time when your room’s walls get extremely heated by the direct rays of the sun. That is why a little more capacity is required to fulfill this temperature gap.

(Step 4 of 4) If Your Room is Directly in Contact with the Kitchen

If your room (where you want to install the AC) is too close to your kitchen, consider buying (0.5 ton) more capacity AC unit. This is due to the fact that additional humidity from your kitchen needs to be eliminated.

AC Tonnage Capacity Calculator

The calculator gives you approximate result which gives you a decent idea how much AC tonnage capacity you need for your room.

Pros and Cons of Buying Large Ton Capacity AC

If you think, a higher ton AC is always better, and you may need to reconsider it again. Here are some valid points.

Tip of the day: If you choose a small size AC for a large room, the AC will take a lot of time to cool the whole area which leads to higher power usage. Also, you get a minimal amount of cooling. So choose your AC tonnage size accurately.

Pros of Large Ton Capacity AC

  • Efficient Cooling in Larger Spaces: Larger-tonnage AC units are more effective in cooling bigger spaces or rooms with high ceilings. They have the capacity to circulate cool air throughout a large area more efficiently, ensuring uniform temperature distribution.
  • Better Performance in High Heat Load Areas: In regions with extremely high temperatures or in spaces where heat-generating appliances are frequently used, a large-ton AC can maintain a comfortable indoor climate more effectively. It can counteract the high heat load and keep the temperature consistently cool.
  • Improved Air Quality and Humidity Control: Higher capacity air conditioners often come with better air filtration systems, which can improve indoor air quality. Additionally, they are more capable of controlling humidity levels, thus creating a more comfortable indoor environment, especially in humid regions.
  • Durability and Longevity: Large-tonnage AC units are generally built to handle more intense usage. They may experience less wear and tear when operating in environments that a smaller unit might find stressful. This can translate to longer life spans and potentially lower maintenance needs over time.
  • Accommodating Future Expansion: If you plan to expand your space in the future or anticipate an increase in cooling requirements (like additional electronic equipment or more occupants), a larger AC unit can accommodate this increased demand without the need for upgrading the system.

Cons of Large Ton Capacity AC

  • Higher Initial Cost: Large-tonnage AC units are generally more expensive to purchase than smaller units. This higher initial investment can be a significant consideration, especially if the extra capacity is not necessary for the size of the space.
  • Increased Energy Consumption: Larger AC units consume more energy to operate. This can lead to higher electricity bills, particularly if the unit is oversized for the space it's cooling. This is not only costly but also not environmentally friendly.
  • Short Cycling and Inefficiency: If a large AC unit is too powerful for a space, it may cool the area too quickly and then shut off, a process known as short cycling. This frequent on-and-off operation can lead to inefficient energy use, increased wear and tear on the system, and inadequate humidity control.
  • Space Constraints for Installation: Larger AC units typically require more space for installation. This can be a significant disadvantage in smaller homes or buildings where space is at a premium, both for the internal unit and the external compressor.
  • Possible Overcooling and Discomfort: An oversized AC unit can lead to overcooling, making the indoor environment uncomfortably cold. This can also create uneven temperature distribution with cold spots, which may not be conducive to a comfortable living or working environment.

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