1. A method for operating a system having variable speed equipment such as heat pumps and air conditioners while (1) achieving optimal comfort conditions in an air conditioned space and (2) maximizing the coefficient of performance (COP) of said equipment; said equipment being characterized by having controls for varying equipment parameters thereof including compressor speed (r), indoor air flow rate (c), and evaporator superheat (t); said system having multiple sensory inputs from which variable comfort influencing data parameters transmitted from said space to said equipment includes dry-bulb temperature (T), humidity ratio (w) and air velocity (V); said method comprising the steps of: providing a nonlinear measure of comfort function CI (T,w,V) based on said data parameters; setting one of said data parameters and calculating default values for the other of said data parameters; calculating a set point value for said comfort function; expressing said function CI (T,w,V) in terms of said equipment parameters as a function of IC (r,c,t); calculating a comfort error (CE) value which is set point value of CI (T,w,V) minus said CI (r,c,t); selecting a nonlinear coefficient of performance function PE (r,c,t) based on said equipment parameters which is desired to be maximized and which is based on the same variables as said CI (r,c,t); and setting said controls to effect maximizing said PE (r,c,t) function while maintaining said (CE) value at substantially a zero value.