There is no reason for alarm if your HVAC system is making some noise, as this is completely normal. After all, this system moves a large amount of air, heats and cools that air, and then distributes it throughout your home. You will hear a low whooshing or humming sound when your HVAC system is operating. However, if the noise is sudden or extremely loud, then you may have something to be concerned about.

At Comfort Systems, our goal is to ensure you know what to look for and listen for so you know when you need to give our team a call. Below, we will take a look at some of the most common sounds that you may hear coming from your HVAC system, what they mean, and what your next steps should be.


When the heat is turned on for the first time in the fall/winter, you will likely hear a clicking noise. Generally, this is nothing to be concerned about; however, if the clicking occurs when the system is on and nothing else, there could be a problem with the ignition system. Give us a call so we can perform a full inspection and diagnose the problem.


It is normal to hear a very slight rattling sound when small debris or leaves get caught in the outside HVAC unit. However, if the rattling sound is constant and loud, it could be something more serious. For instance, a loud rattling noise could indicate that a bolt has become loose or the motor is failing. It is important for a technician to check out this problem immediately to avoid further damage.


A short squeal is actually normal when the system is first starting or shutting down. However, if the squeal is persistent, it may be a sign that the fan belt or blower motor is malfunctioning. If you are able to check and see that the belt is worn, replace it. If the squealing continues, contact us at Comfort Systems.


Any kind of loud clanging or banging noise with your HVAC system is not normal. This particular noise indicates a loose or broken component within the system which may include a piston, rod, or crankshaft. Turn off the HVAC system immediately to avoid further damage and call a technician for assistance.


If you notice that your HVAC system is making a weird buzzing noise, there may be a problem with the compressor. At the same time, though, it could be a refrigerant leak or a loose part. Since there are multiple culprits, it is recommended to have a professional HVAC technician inspect the system.

Comfort Systems: Your Professional HVAC Repair Team

At Comfort Systems, we have spent years in the HVAC business and understand the inconvenience of a broken HVAC system. For that reason, we will quickly and efficiently address any issues you are having so that you get back to a comfortable environment as soon as possible. Contact us today to schedule an appointment.