It’s that time of year when many of us are cranking up and turning on our heating systems for the first time in awhile. If you’re a commercial building owner and you’ve noticed some strange noises coming from your heating systems, we’ve put together this guide of common HVAC noises in order to help you diagnose the problem and fix it. 

It’s essential that your building’s heating system works properly now that we’re officially in winter. Maintaining a comfortable indoor temperature is important for the health of everyone in your building, especially when it’s cold outside. Heating system sounds are common, and if you’re hearing any of the sounds explained below, give us a call today.

Squealing or Screeching

When you turn on your heating system do you hear a squealing or screeching sound? This noise probably means that one of your fan belts has gone bad and needs to be replaced. A squealing or screeching noise may also indicate that the motor needs lubricating. We recommend calling an HVAC technician who can check your fan belts and ensure the motor is properly lubricated.


It’s common to hear popping sounds coming from your heating ducts when they haven’t been used in awhile. The pops you hear are the metal ducts expanding when the warm air rushes through them – they’re expanding and contracting in response to the temperature changes. Popping noises when your HVAC system first turns on are normal, and are not cause to be concerned. 

However, if the popping continues and starts to sound more like rattling, there may be several reasons. It’s common for the ducts in older HVAC systems to come loose when the sealant wears off. When this happens it causes the duct to shake and vibrate when you turn it on, resulting in a rattling sound. If this is the case, please call an HVAC technician and schedule an inspection.

Frequent Clicking

Similar to popping sounds, heating systems often make clicking sounds when you turn them on for the first time in awhile. This is normal and not cause for concern. If some time passes and the clicking doesn’t stop, it may actually indicate a problem with your furnace’s ignition system. Have a technician check it out before the problem gets worse.


Most HVAC systems make a very slight humming sound while they’re running, but if the humming noise is abnormally loud or you notice it stopping and starting, something might be wrong. Check to see if you can pinpoint where the noise is coming from then call an HVAC technician to investigate. 

Humming noises aren’t generally indicative of big problems, rather they most often mean that your heating system simply needs a little maintenance. Parts might need replacing or repaired, which is a normal part of maintaining a commercial HVAC system.

Regular HVAC Maintenance with Tri-Tech Energy

Your building’s heating system is a complex machine with many components, each one dependent upon the other. We recommend investing in regular HVAC maintenance to ensure your heating system stays in top condition. It’s much more cost-effective than waiting until something goes wrong and paying for more costly repairs. 

Don’t wait until the coldest winter days to sort out any strange sounds coming from your HVAC system. Keep the occupants of your building warm and comfortable by investing in regular HVAC maintenance, and by taking care of any noises as soon as you hear them. 

For more information about how we can help you with commercial HVAC maintenance including diagnosing common HVAC noises, please contact our team at Tri-Tech Energy today or visit our website at: