Loud Noises Coming From Your HVAC? Here’s What To Do

Imagine finally getting the exhausted baby to sleep and then hearing loud noises, “TAP TAP TAP BAM BAM CLANG BANG!” that rudely yank your precious angel from their peaceful snooze. Then, you realize it’s your air conditioner, the only machine that can keep your family cool (and sane) during the hottest months of the year. Panic sets on even more.

But, don’t fear just yet. You can call an HVAC tech to give your machine a tune-up, or you can try to diagnose the problem yourself.

A properly functioning HVAC machine should operate quietly on its own without being a significant disruption. It might buzz or hum, but it shouldn’t make any obtrusive banging or scratching noises. If loud noises are coming from a unit, it could be time for electrical/mechanical repair and maintenance.

DIY HVAC Diagnosis

Be careful because some of these alarming noises could be a sign that a serious malfunction has occurred within the unit, and it might need to be handled right away by an HVAC professional. Make sure that you listen carefully to see which types of warning sound it might be so that you can get the problem resolved as soon as possible.

Loud Striking or Shaking

Any shaking or rattling noise in an outdoor air conditioning unit could be a sign that the motor/blower assembly or the metal cage fasteners are loose. The fasteners are on the metal casing that encloses the condenser and should be tight. To secure the cage and keep it in place, the bolts or screws might need to be tight.

If there is an issue with the motor or blower assembly, the work involved will be slightly more complicated. However, it needs to be taken care of because it can quickly turn into a deeper bang that’s even louder if the loose portion becomes completely separated. When this problem occurs, it’s best to turn off the HVAC unit. You could either find the loose part yourself or contact an HVAC professional. You might be dealing with a motor beating, blower, or mount that has come loose.

Vibrating or Buzzing

An outdoor unit that hums might have a dead capacitor. However, the compressor within the unit still considers it a power source and will still try to pull from it. If this happens, the whole compressor can burn out, which then requires expensive servicing.

An HVAC unit that won’t switch on and has a humming sound instead of clicking is likely not receiving power from the capacitor. If this occurs, switch the unit off quickly to ensure there is no additional damage. Typically, certain parts tend to fail when it’s the hottest outside. HVAC units have to expend the most energy in the warmer months.

Screeching Sounds

If the blower motor is squeaking, it might be time for a new motor bearing or belt. It’s essential to have the belt replaced before it becomes entirely broken because a damaged belt can restrain the blower from working. Blower motor units that have oil ports might need some oil to lessen the motor’s sounds. Finding the right type of motor oil can be difficult, so figure out what your exact HVAC unit needs before you decide on one.

Shrieking or Whistling Sounds

If it sounds like the condenser unit on your machine is producing a whistling noise, it’s probably a refrigerant leak or a lot of pressure inside the unit. Since both scenarios can be extremely hazardous, call a professional as soon as you can. A good company will be able to send a technician out right away.

Random Clicking

Outdoor units that are being switched on or off will click, but if the unit is operating normally and the internal cabinet begins to click, you might have a problem. Capacitors that are beginning to wear down might click and could soon require replacement. The capacitor acts as a substitute battery supply for the compressor, outside fan, and blower motor.

Like all batteries, capacitors have sensitive parts that can become worn out from use. A capacitor that isn’t functioning correctly can put the compressor through too much pressure, which might even overheat until it malfunctions. This can all harm the HVAC system. Turn off the unit right away if you think the capacitor might be the reason the HVAC is clicking. A technician will need to replace the capacitor.

Objects Scratching Against Metal

If you hear scraping noises that sound like metal, there could be an issue around the blades. If a foreign piece of wiring or twig fell inside, it might be hitting the blades of the unit or the fan motor. You’re going to want to try and retrieve the object because if the fan bends, the blade can press too hard against the coil tubing and fins.

It could also result in a loss of refrigerant, which will severely reduce the cooling and heating efficiency of your unit. Turn off your HVAC unit right away to try and minimize further damage. Try to clear any debris and clean the unit once every few weeks. Inspect the machine visually for damage. A monthly maintenance routine can help keep your unit in tip-top shape.

HVAC Preventive Maintenance is Key

Keep these HVAC preventive maintenance tips in mind to extend the life of your machine and increase its efficiency.

Replace the Filter As Needed

The majority of HVAC units require pleated filters (these have a 3-month life cycle) or fiberglass filters (monthly life cycle). Regardless of the type that your unit takes, monitor it routinely. If you see that the filter is starting to get especially dirty, it’s time to get a new one, even if it’s not time yet. HVAC units have to work twice as hard to push air properly when there is a dirty air filter. This isn’t good for the unit because it can break the fan and cause other areas of the machine to wear down.

Ensure the Area Around the Machine Stays Tidy

Outdoor HVAC units are prone to getting grass, twigs, pollen, dirt, and leaves stuck inside because of wind and weather. Don’t be afraid to use the hose if you have to. Do a thorough job and clean it routinely. If you’re mowing your yard or are having someone do it for you, be sure to make a point of not letting the grass clippings blow into the unit. Typically, allowing two feet around the unit is best. Don’t clean anything without unplugging the unit from power.

Don’t Forget to Turn on the Fan or Open a Window

While it’s nice to have nearly ice-cold air blowing on you when it feels like it’s scorching out, it’s still healthy for your HVAC unit to run the fan now and then (or to get a break because of open windows.) The fan doesn’t put as much wear and tear on your unit, and on colder days it’s good to give your trusty air conditioner a break.

Adjust Your Thermostat

When the weather starts to get colder, it can help to reset the temperature on your thermostat. Automatic thermostats are helpful to save time so that you don’t have to do it daily. When you don’t need the air conditioning as much or aren’t home, keep it off or turned down. This will reduce the wear on your unit.

Consider Installing New Insulation

Older homes with poor insulation might have trouble retaining the expensive cool/warm air you have inside. This will cause your unit to overwork itself to keep producing new air. Don’t hesitate to have an energy audit conducted in your home, or contact a professional to improve your insulation for you.

Monitor the Condenser

The condenser is a common culprit for getting obstructed because it’s outside. Check it regularly to be sure there isn’t damage, and don’t let any overgrowth occur near the area. There should be plenty of room for airflow.

Keep an Eye on the Evaporator Drain

In an HVAC unit, the evaporator drain accumulates the humidity in the air that the system gathers. If this drain gets to be clogged, it can cause issues. Check on it regularly and clean it at least once per year. You can use a mixture of bleach and water poured into the drain to get rid of any mold or algae.

In summary, those who have HVAC units should keep them maintained to reduce the overall repairs that could be required. If you can be careful about addressing the issues when they arise, you can avoid serious problems and save a great deal in repair expenses in the future.

Also, if something breaks, you’ll feel better knowing that you’ve kept the HVAC machine in the best shape that you can. The outcome will be far better than if the machine had not been maintained at all. Additionally, well-maintained HVAC systems use far less energy, which makes a big difference for the planet when more people jump on board.