Common HVAC Noises and What They Mean

Home » Common HVAC Noises and What They Mean

Person pressing ear (listening intently) against an HVAC unit

HVAC systems are designed to provide comfort and maintain optimal indoor air quality. However, these systems can sometimes produce various noises indicating underlying issues. Aloha Air Conditioning offer the most effective and efficient services for HVAC repair in Livingston, TN, and below are some of the most common HVAC noises we address and what they may signify.

Rattling or Banging

If you hear rattling or banging noises, it may be indicative of loose or broken components within the system. Loose screws, unbalanced fan blades, or damaged motor bearings may be the culprits. It’s essential to address these issues with a prompt HVAC service appointment to prevent further damage.

Hissing or Whistling

These noises typically suggest air leaks within the HVAC structure. Most HVAC contractors agree that leaky ductwork or improperly sealed vents can cause air to escape, leading to reduced system efficiency. Fixing the leaks and ensuring proper sealing is crucial to maintain the system’s performance.


A grinding noise often means a malfunctioning motor or worn-out bearings. Ignoring this noise can lead to severe damage and potential system failure. Consulting qualified HVAC technicians is essential to promptly diagnose and rectify the issue.

Squealing or Screeching

These high-pitched noises are commonly associated with fan motor or blower belt issues. The belt may slip or wear out, or the motor bearings require lubrication. Addressing these problems during routine HVAC maintenance can prevent further damage and ensure smooth operation.


Occasional clicking sounds when your HVAC system is turned on or off are usually normal. However, persistent clicking noises might indicate a faulty relay or control issue.

Any unusual or persistent noise from your system should not be ignored. Regular maintenance and timely repairs are crucial to keep the system running efficiently and extend its lifespan. Contact Aloha Air Conditioning today to keep your HVAC unit in tip-top shape!



From monthly A/C maintenance and duct cleaning to heater installation, clean air quality checks, and any other HVAC service you need – we do it all.