Are you Hearing Something New from your HVAC Unit?

Air conditioning units will always make some kind of noise, but what should you do when you start hearing new and different noises coming from your unit?

Firstly, it’s important to note the age of your unit. Older HVAC units are louder than newer models that have been designed specifically to run more quietly. If you’re moving into a new house and your unit seems exceptionally loud, it may just be an older model than you’re used to. There are ways of dampening the sound from the unit, but you’ll want to get in touch with your local HVAC maintenance professionals to determine the best way to suppress the noise without messing up performance.

There are some sounds that you can always tell are not normal though. It’s the same principle as your car. When you hear a new and strange noise coming from your car, you take it to the mechanic to get it checked out. By that logic, when you hear a violent rattling coming from your HVAC unit, it’s probably a good idea to call a professional to come look at it. Chances are if you catch the problem before it gets worse it could save you hundreds or even thousands of dollars in repair and replacement costs.

What is Normal and What isn’t?

Generally HVAC units should make a steady whirring sound when working correctly. As long as the noise coming from your unit sounds even and regular, it’s probably working just like it is supposed to.  After all it is a huge machine with a lot of moving parts, so it’s bound to make a fair amount of noise just on its own.

There are some things you should get checked out immediately though. The first thing you should do upon hearing any kind of grinding or rattling is turn your system off. If it’s outside or in a place that you can visually check it, it’s probably a good idea to take a look at it. You shouldn’t bother taking it apart or anything but check to make sure there isn’t a giant stick coming out of it or something obvious. Once you’ve turned your unit off and verified that it’s a tree didn’t fall on it and it’s not full of squirrels or something, give your local HVAC professional a call to come check and make sure everything is working properly. They’ll be happy to come take a look at your unit.

Common Sounds and What They Mean

Grinding – Generally when you hear grinding coming from your air conditioner, it has something to do with the fan motors. This is usually your first warning that something is going wrong with the motors, such as worn bearings or a lack of proper lubricant.

Hissing – Hissing or whistling usually has something to do with the ductwork in your home or business. Though if you hear it coming from the AC unit itself, you may be dealing with a refrigerant leak. This is a job that should only be handled by a professional. Do not attempt to fix this on your own (unless you’re an HVAC specialist, of course).

Rattling – Rattling is one of the most common noises that homeowners hear coming from their unit. Often this is caused by outside debris falling into the vents of your system and causing things to rattle inside the unit. It could also be a result of loose screws or bolts. In serious cases, rattling may be coming from your compressor, which probably means that it is starting to wear out.  As compressors age, they get louder and start to make new and different noises, which are usually the first sign of a problem.

Popping – If you’re hearing popping sounds when your air starts up or shuts off, it’s likely that you have some sort of issue with the ductwork in your home. As your ductwork ages, various things can start to cause problems, such as worn seals, or small tears, and like anything else it requires maintenance to remain in top working condition.

Preventing Noises in the First Place

One of the most important things that you can do to keep your HVAC system working properly is changing the filter regularly. Usually the packaging will tell you how often you should replace your filter, but make sure you take into account things that are going to clog up your filter faster. If you have excessive dust, pet hair, or smoke cigarettes regularly, these things can cause your filter to clog up faster and require you to change it more frequently.

In addition to keeping your filter clean, you should sign up for a regular maintenance plan with your local HVAC professional. Our local shop, Bradley Mechanical, offers regular maintenance plans, which make it easy to keep up on our HVAC maintenance. Chances are your local HVAC dealer will also be able to provide you with some kind of annual or semi-annual plan to check and make sure your HVAC system is ready to keep you warm in the winter and cool in the summer.

By following these two steps, you probably won’t ever have to deal with the different sounds mentioned above. If you are hearing the sounds, don’t panic, just call your local expert and they’ll be able to help you get your HVAC unit back to peak performance.