Chimney-style range hood with a glass canopy over a cooktop
Generic photo: Bilguun Gantumur · Pexels License

Hood blower hums but won't spin (capacitor)

A weak run/start capacitor or a greased-up blower wheel are the common causes. A switch fault or seized motor is next. No hum at all points to a thermal fuse, switch or supply.

Cross-checked ~45 min moderateBrands: All

Before you start

  • Turn off the breaker before opening the hood or touching wiring
  • Use a non-contact tester to confirm power is off
  • Capacitor terminals can shock: discharge or handle by insulated tools

Diagnostic steps

Unlock all 3 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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Hood blower hums but won't spin (capacitor) · OnCall Tech