The Shift from AC to EC Motors
Historically, Fan Coil Units (FCUs) utilized standard shaded-pole or Permanent Split Capacitor (PSC) AC motors. These are highly inefficient at partial loads. Modern engineering demands Electronically Commutated (EC) motors—brushless DC motors with integrated inverters. EC motors maintain peak efficiency across their entire RPM range, slashing decentralized HVAC electrical consumption by up to 50%.
Acoustic Attenuation in Occupied Zones
Because FCUs are installed directly within occupied zones (hotel rooms, hospital wards, offices), acoustic performance is heavily scrutinized. EC motors eliminate the low-frequency electrical hum associated with AC voltage modulation. Paired with forward-curved centrifugal impellers and internally lined acoustical foam chassis, modern FCUs achieve ultra-low Noise Criteria (NC) ratings while maintaining strict chilled water Delta-T.