January 10, 2024
HVAC services

We get so used to the normal sounds of a heating, ventilation, and air conditioning system that they tend to become part of the background and are easy to ignore. You likely don’t notice them at all unless the equipment stops working correctly. An efficiently running furnace likely has a gentle hum, with the occasional whoosh of air as it rushes through the fans. When it’s not working correctly, you might hear anything from banging and clanging to clicking and squealing.

If you notice a change in the sounds of your heating system, call an HVAC professional immediately. Some noises indicate a serious problem, such as a gas leak, which can be dangerous to you and your family.

Clanging or Banging

Clanging or banging usually means a part is malfunctioning. It could be a poorly positioned fan or a loose blade. Banging can also indicate a duct problem. Ducts often make popping or creaking sounds as conditioned air circulates and triggers temperature changes. However, loud noises can also indicate an air pressure or air return problem.

If you hear these noises, shut down the system and call for professional help. Continued use of equipment can cause wiring short circuits, create more damage to affected parts, or damage various components.

Squealing or High-Pitched Whining

These unpleasant noises signal a problem that should be investigated quickly. Squealing can indicate a bad bearing, loose fan belt, or a worn motor. Remedies vary from simple fixes, such as lubricating moving parts, to expensive repairs, like replacing a failing motor.


Gas furnaces may click when the ignition engages. Repeated clicking can signal a problem with the electrical system, relays in the thermostat, or a faulty contactor. If the clicking occurs when the furnace starts up, investigate immediately. In gas furnaces, the ignitor system opens a gas valve to light the burners. A faulty valve may allow gas to build up, which can cause a leak or fire. A dirty flame sensor may click because it can’t sense whether the burner flame is on or off. Faults in gas furnace components are dangerous. Call a professional to evaluate and repair them.

Brian’s Heating and Cooling Inc. in Madera, CA recommends seasonal tune-ups for HVAC equipment. During furnace maintenance, our experienced professionals examine and clean each component, including burners, piping, ignitors, and heat exchangers. Tune-ups reduce the likelihood of breakdowns or expensive repairs and ensure equipment runs efficiently. We also offer new installations as well as repairs and maintenance of furnaces, heat pumps, ducted HVAC systems, and ductless mini-splits.

If your furnace is making unusual noises, contact the experts at Brian’s Heating and Cooling Inc. today for an evaluation. We work on all major brands of residential and commercial HVAC equipment.

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