No matter the age or the brand of your HVAC system, it will make some noise as it runs. When your unit performs normally, you should expect to hear the usual “hum” as it operates through its cycle. However, your system may make other sounds from time to time as it runs. Some of these noises are more common than others, with each sound suggesting something different going on with your HVAC unit.

A few of these noises are not really cause for concern, but other sounds indicate an immediate need for professional assistance. Find out more about 12 of the most common HVAC noises and when you need to take action and make a service appointment to have them addressed.

1. Popping

When you hear a popping sound coming from your HVAC unit, it usually means the expansion of the ductwork due to air blowing through the ducts. This is normal and not typically a cause for concern. However, you can look into getting some duct insulation to help dampen the popping noises if you don’t want to have to continually listen to them whenever the system kicks on.

2. Squealing or Screeching

Squealing or screeching noises could indicate a couple of things. You may have a bad fan belt. Letting this issue go could result in the belt eventually breaking, so have a technician come over to investigate. The belt may just need some lubricant, or it may need a complete replacement. Your technician will let you know what type of service you need after a review of your HVAC device.

These screeching or squealing sounds could also indicate a motor-bearing issue. As with the bad fan belt, you should have a professional check the unit to find out if it’s indeed a motor-bearing problem or if it’s something else.

3. Buzzing

A constant buzzing coming from your HVAC system could be an indicator of one of many issues. There may be a part that’s loose and causing the vibrations.

A buzzing could also suggest fan blades that became unbalanced. The noise could also indicate a malfunction of the compressor, debris that found its way into the system, or a refrigerant leak. Always have a technician check the system to determine the buzzing sound culprit, especially if you think you might have a refrigerant leak. Only certified technicians can handle refrigerant.

4. Clicking

If you haven’t used your comfort system in a while, then hearing a clicking noise when you do finally turn the system on most likely means the unit’s just warming up at the start of its cycle. It may also mean that it’s at the end of its cycle and getting ready to turn off. Beyond these, though, clicking sounds could be a result of a number of issues.

There may be an electrical issue or a problem with the relay. You might also have an issue with the thermostat or the ignition system. A professional from Paradise Home Services can come over and work to find out what’s going on.

5. Rattling

As with buzzing noises, rattling sounds emanating from the unit might indicate debris or a loose part. You could also have a more serious issue with your system, such as a failing compressor. As with most of the other sounds on this list, an experienced HVAC professional should be the one to examine your unit to try and find out what’s causing the rattling sounds.

6. Hissing

Hissing noises coming from your unit might mean you have leaky ducts. You might also have a refrigerant leak or an inordinately high internal compressor pressure, or you may just have an air filter that’s incompatible with your device. Regardless of the cause, you’ll want an experienced technician to perform a system check and inform you of the cause of the hissing.

7. Banging

Banging sounds could indicate a problem with the blower assembly, or it might just be that a part became loose but could soon break off entirely. Turn off the unit and reach out to Paradise Home Services in Navarre so we can send someone out to inspect the system.

8. Rumbling

Rumbling noises are usually indicative of an issue with a dirty burner. With this problem, it just means that the burner needs a thorough cleaning. This is something you could do yourself as it requires vacuuming any dust that’s accumulated near the burner and base of your furnace. However, it’s better to consult with a professional HVAC technician to first determine exactly what the issue is that’s causing the rumbling. You wouldn’t want to perform cleaning only to discover later it didn’t fix the issue that’s caused by something else entirely.

9. Humming

As mentioned previously, your heating and cooling unit should produce a steady hum as it runs. However, humming that appears to be louder than normal is not usual, and it’s something you’ll need to have checked out.

A humming sound might mean you have a bad motor, or you may just have a loose part somewhere within the system. You may also have a defective relay switch. No matter what the issue is, these possible causes of the humming sounds aren’t things you can easily check yourself, so let a professional do it for you.

10. Booming

If you’re hearing booming sounds coming from your furnace, it usually means it’s having trouble with lighting the pilot or igniting. The gas can build up over time and then ignite, causing a booming noise. An issue involving a possible gas buildup is not something you should take lightly, so call in a professional immediately.

Another possible cause of this booming noise is that the ductwork keeps contracting and expanding. While not as serious as a gas buildup, an issue with the ductwork is still something for which you should have an experienced professional investigate.

11. Bubbling

Bubbling noises could mean a leak in the drainage pipe, or it could mean excess moisture resulting from a blockage or a crack in the pipe. The problem also might be because of gas bubbles in the refrigerant line. Whatever the case, this issue calls for the expertise of a knowledgeable technician.

12. Grinding

Your system producing grinding noises may mean that you have some sort of issue with the compressor. In this scenario, the compressor’s pistons could be the ones causing the grinding.

Call Us Today

At Paradise Home Services, we are proud to serve residents of the Florida Panhandle. Our service offerings include heating and cooling repair, installation, and maintenance. We also provide indoor air quality checks and duct cleaning in addition to a range of plumbing services like drain cleaning and sewer line repair. If you’re hearing unusual noises coming from your HVAC system, or you have another issue you need to have checked out, call Paradise Home Services today to have an experienced technician come out for an assessment.

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