ABSTRACT
In most unitary heating, ventilation and air conditioning (HVAC) systems, coefficient of performance (COP) and fan properties are the two key aspects that govern their energy consumption. Higher COP is associated with a reduction in energy consumption. Unitary systems require a fan for blowing air over the condenser as well as evaporator tubes. A fan is characterized by its static pressure and volumetric air flow rate. High static pressure and flow rate help in achieving setpoint faster, however, they are also associated with higher energy consumption. If these parameters are not specified properly, results of the energy model could significantly deviate from the actual performance. This chapter explains the method of modelling unitary systems by specifying COP and fan properties. It also explains how to evaluate the impact of unitary air conditioner COP, the impact of the fan efficiency of a unitary air conditioning system and the impact of fan pressure rise.
