How to Size Air Con Compressors

Commercial air conditioning units come in a variety of sizes, depending on how large of a compressor the model carries. Choosing an air conditioning unit that is the proper size is important. If the unit is too small, it will be overworked and struggle to keep the area cool. Air conditioning compressors are rated according the British Thermal Units, which is a number that corresponds to how much surface air can be affected by the unit's performance. Understanding this calculation will make it possible to select an air compressor that is the proper size.

Things You'll Need

• Tape measure
• Calculator

Instructions

1. Measure the floor space using a tape measure. Measure the length and width of all rooms that will be serviced by the air conditioning unit.

2. Measure the ceiling height from floor to ceiling in each room that will be serviced by the air conditioning unit.

3. Calculate the cubic feet of the space. Multiply the length times width times height to determine the cubic feet of the space that will be serviced by the air conditioning compressor.

4. Select an air conditioning compressor that corresponds to the size of the space to be cooled. For example, if the space consists of 10,000 cubic feet, select an air compressor that is 10,000 BTU or greater.

Tips & Warnings

• It is better to have a compressor that is too large rather than too small. Choose the smallest compressor you can without going under the cubic feet measurement.

References

• "Air Conditioning and Refrigeration" by Rex Miller and Mark Miller (2006)
• Rheem: Choosing an Air Conditioning System
• Energy Star: Properly Sized Air Conditioners