Have you ever wondered, Why capacity units of the domestic refrigerator and Air Conditioner (AC) are different though both are refrigeration systems? What is the basic difference between them with respect to the cooling capacity?
The capacity of the domestic refrigerator is normally rated in ‘Litre’. A liter is actually a unit of volume and it is applicable to the domestic refrigerator while dealing with space/volume to be cooled. Thus, liter capacity actually indicates the volume or space to be cooled by the domestic refrigerator.
On the other hand, the cooling capacity of the Air Conditioner (AC) is given by the term ‘Ton of refrigeration.
What is one Ton refrigeration?
‘Ton’ is actually a name given to the amount of heat to be extracted from 1 short ton (907.18474 kg) of water at 0 degrees C to convert it to the ice at the same temperature in 24 hours. (Note: 1 large ton = 1016.0469 kg, 1 metric ton = Tonne = 1000 kg)
In other words, the refrigeration rate required freezing 1 ton of water to the ice for 24 hours at 0 degrees C.
Thus, 1 Ton of refrigeration = 1 TR = (latent heat of ice)x(amount of water)/time
= 334 x 907.18474 /(24 x 3600)
= 3.50 kW
So, both refrigeration system has different capacity term namely ‘Litre’ (Space to be cooled) and ‘Ton’ (3.5 kW) energy to be removed for cooling).
Nicely expalined. Will come handy next time while buying new AC.