Why is My HVAC System Making Loud Noises?

Table of Contents

1. Banging or Clanking

  • Possible Cause: Loose or broken parts in the blower assembly or compressor.
  • Fix: Turn off the system and inspect for loose screws, bolts, or damaged components.

2. Buzzing or Humming

  • Possible Cause: Electrical issues, such as a failing capacitor or contactor.
  • Fix: Call an HVAC technician to inspect the electrical components.

3. Rattling

  • Possible Cause: Loose panels, debris in the system, or failing motor bearings.
  • Fix: Tighten panels, remove debris, and lubricate bearings if necessary.

4. Whistling or Screeching

  • Possible Cause: Airflow restrictions, worn belts, or motor issues.
  • Fix: Replace air filters, check for duct blockages, and inspect the blower motor belt.

5. Hissing

  • Possible Cause: Refrigerant leaks or duct leaks.
  • Fix: If refrigerant is leaking, contact a professional immediately.

6. Clicking

  • Possible Cause: Relay or capacitor failure.
  • Fix: If clicking occurs continuously, have an HVAC expert inspect the system.
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