TABLE OF CONTENTS All manual load calculations and many of the computer programs assume that a static or steady-state condition exists. But steady-state conditions do not exist in an air conditioning situation. If the HVAC systems and controls are functioning properly, then the indoor environment will vary only slightly. However, the internal and external loads are constantly changing. The function of the cooling load factor (CLF) in the calculation is to approximate the effect of these transient factors so that the static load calculation will yield results more like the real dynamic load.
The research which led to these factors resulted from the widely recognized condition that older calculation methods invariably led to oversizing of HVAC systems and equipment. The increases in energy and equipment costs during the 1970s led to a broad acceptance of the new methods because, in general, overall operating efficiency decreases if equipment is oversized. Even so, the factors in the tables are conservative, and some oversizing will normally result.
