Better Unitary Equipment Air-Handlers for Efficiency and Humidity Control

摘要

Regulatory requirements drive unitary equipmentdesign. For residential equipment, SEER reflectsperformance at moderate temperatures, and is largelyindependent of high temperature efficiency and highlatent heat removal capability. The test proceduregives too little credit for advanced air handlers thatreduce air conditioning load and facilitate adaptivehumidity control through automatic fan speedadjustment. DC permanent magnet variable speedmotors have much lower market share than lessefficient permanent split capacitor designs: changingsaves 15% - 25% at high fan speed, and at least 50%at lower speeds (high latent cooling). Humidistatsallow dynamic humidity control by reducing air flow,cooling the evaporator. Following markettransformation to increase market share, federalequipment stanards should be augmented to includespecific air handler air flow efficiency levels, such as0.2 watts/cfm at size-dependent static pressures. Weestimate that customer payback will be less than threeyears in a mature market.