What Is One Ton Of Refrigeration?

One Ton of refrigeration which is shortened as TR or TOR is the term used to determine the heat transfer rate required to freeze one short ton of pure water or to melt one short ton of pure ice at the temperature of 0°c within a day.

It is commonly used as a unit for power to interpret the capacity of heat extraction of some appliances such as air conditioners and refrigerators.

In some countries like the US, the capacity of a few types of equipment such as air conditioners and refrigerators are identified as a TR or TOR. However, BTU/h is used by some producers too as one ton of refrigeration is roughly synonymous with 12,000 BTU/h or 3.5kW.

The equivalence of 1 ton of refrigeration to 3516.85W has been specified by ASHRAE which is expanded as the American Society of Heating, Refrigerating, and Air Conditioning Engineers. 

It is a generalized term used very often to give an idea about the power or magnitude of a refrigeration unit and can be interchangeably used with 3516.85W.

Now, the question that arises is why ton has been used as a unit of power or capacity of refrigeration.


It might confuse you that a ton, which is a measure for weight, has been used to measure heat transfer rate and the answer to this question exists years ago when there was no such thing as air conditioners or refrigerators.

Several years back, huge blocks of ice used to be the thing that was frequently used to cool houses or places. People used to keep the blocks of ice in their houses along with a fan placed above the ice block, so that ice and fan could produce cool breeze and cool down the surrounding temperature. 

To cool the surrounding ice absorbs the heat which results in the melting of ice,  a ton is the amount of heat required to melt down one ton of ice and to meet such an amount of ice 286,000 BTU is required.

This is how one ton came into existence as the measure of heat transfer rate Or cooling capacity of an equipment. 

The refrigerators and air conditioners tend to remove the heat from the surrounding, which is somewhat similar to the working of ice blocks that used to provide cool breezes, and hence a ton is still relevant to measure the capacity of refrigerators or air conditioners to remove the surrounding heat.


Tonnage, which is the capacity of cooling of an air conditioner, is a huge factor to be considered before buying an air conditioner. The tonnage of your air conditioner should be appropriate for the size of your room, only then the air conditioner would be fully efficient for you. So understanding tonnage or 1 ton of refrigeration is crucial for you to buy appliances such as air conditioners. 

One Ton of Refrigeration has many real life benefits as it gives a proper measure of heat transfer rate or cooling capacity of any appliance, and hence you can decide which appliance to buy accordingly. 

I hope now you have understood what one ton of refrigeration actually is and how much significance it has. 

You can use this knowledge about one ton of refrigeration to understand the capacity of an appliance and to get an idea about the power of that equipment. 

You can also try to understand one ton of refrigeration by converting it into watt or kilowatt, if understanding those units are convenient for you. 

I wish you all the very best!