How to calculate Air Conditioning Tonnage for Room

Sometimes we face problem to calculate proper AC according to size of the room. If we select proper AC then, we can run the AC for long time as well as save money for over size.Step#01:

Calculate volume of the room.

Volume = (Length*Width*Height)  feet³

Step#02:

C1 =  Volume * 6 BTU/hr (Multiplication Factor 6)

Now, we’ve to consider how many average people will stay in this room.

C2 = N * 500 BTU/hr  (N= Number of persons)

Step#03:

So, Cooling capacity = C1 + C2  BTU/hr

 

Example:

Room length = 12 feet, Width = 12 feet, Height = 12 feet

So, Volume = 12*12*12 = 1728 feet³

C1 = 1728 * 6 = 10368 BTU/hr

C2 = 4 * 500 BTU/hr = 2000 BTU/hr

So, Cooling capacity = C1 + C2 = 10368 + 2000 = 12368 BTU/hr

One Ton=12000 BTU/hr.

So we need approximate one TON AC for this room.