About this Video

• Video Title: HVAC Blower Motor Operation and Current Draw during Airflow Restriction! ECM vs PSC
• Channel: AC Service Tech LLC
• Speakers: Craig Migliaccio
• Duration: 00:06:27

Introduction

This video demonstrates the effects of restricted airflow on HVAC blower motors, comparing the performance of ECM (Electronically Commutated Motor) and PSC (Permanent Split Capacitor) motors under these conditions. The presenter simulates low airflow and measures current draw to highlight the differences in energy consumption and potential motor damage.

Key Takeaways

• ECM motors draw significantly more current when airflow is restricted, attempting to compensate for increased static pressure. This increased current can lead to higher electricity bills and potential motor module failure.
• PSC motors show less dramatic current increases with airflow restriction. They are less likely to be damaged by restricted airflow but the system may overheat.
• Restricted airflow (e.g., clogged filters, collapsed ductwork) leads to higher energy costs and potential equipment damage regardless of motor type. Regular maintenance is crucial.
• The video provides a visual comparison of current draw and static pressure changes for both ECM and PSC motors during airflow restriction.
• The presenter offers additional resources in the video description for further learning about troubleshooting blower motors and refrigerant charging.