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5 common HVAC noises and what do they mean?

Submitted On April 29, 2017

Are your HVAC noises keeping you up all night? If yes, you should probably explore in detail about the different types of HVAC noises to make sure what is normal, what is not. There are several homeowners who feel worried for the strange noises that they hear from their systems, however. the truth is, not all noises are worth worrying for. Some are just normal sounds that systems make as they run. Here is a description of some common HVAC noises and what do they really mean:


Well, I personally love the sounds of rattling leaves and therefore, can enjoy the one coming from my HVAC system but that's insane to do so since it's synonymous to risking my HVAC system which I certainly do not. Basically, the rattling sounds usually come from the vents and the reason is simple I.e something is stuck in the vents. The return ducts suck air so things that are placed close to them sometimes also fall into the ductwork accidentally that then produces a rattling sound. In order to troubleshoot this problem, open the vent and remove whatever is stuck there. In case it has gone far towards inside, better call a professional.


Was the buzzing of the bees not an enough irritation that now we'll have to hear the buzzing of HVAC system? Well when is comes to buzzing, such a noise usually comes from the outdoor condenser unit of Ac or heat pump and there are mainly two possible reasons of that:

1. It could either be due to excessive unit vibration which is usually because of loose parts. Tighten any screws that you easily can and the noises will go silent. (most probably)
2. The other possible reason is over aged motor. If that is the case, call a professional and consider replacement of the motor.


Banging noise comes from the Furnace when it is turned on. This happens as a consequence of delayed ignition and delayed ignition takes place when there dust and debris accumulated on the ignition unit or burner. Cleaning time!


The clicking sound is normal at the start-up and shutting down of appliances. However, constant clicking is not normal. Constant clicking can be due to a failing Thermostat or a faulty control system. Another possible reason could be a damage in the electrical parts of the appliance. Check thermostat and remote control first. If they both seem to function okay, call a professional for a pro check up to fix the clicking HVAC noises.


O gosh! What does screaming usually symbolises? Danger! O yes, danger. The sound of screaming or high pitched whistling from the Air Conditioner units is not to be taken non-seriously neither can it be treated with DIY methods because the cause of screaming noises from the HVAC system is, leaking refrigerants. Leaking refrigerants only harm the system but are also extremely dangerous for the health of the residents so, take the sound seriously. No DIY! Shut off the Air Conditioner and call professionals.

Bottom Line

As said already, not all HVAC noises are a symbol of danger, however, some are. In order to minimise the possibilities of danger and health risks, it is important to know about the nature of these noises so that one can easily figure out what to do when such noises are heard. If you're battling with any kind of strange HVAC noises and are unsure what to do, there's something we can help you with. A certified and authorised technical assistance. Connect anytime on our Toll-Free numbers: 1-855-245-4328

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