6 Problematic Air Conditioner Noises That Require Immediate Attention

As the weather gradually starts getting warmer, the last thing you need is strange air conditioner noises – especially in the middle of a summer heatwave.

Millions of Aussies rely on air conditioning for efficient heating and cooling at home. Therefore, it makes a lot of sense to understand how your air con works, identify possible faults and recognise signs of damage.

Of all the potential issues, weird sounds coming from a noisy air conditioner are among the most obvious indicators of a likely fault. And by catching faults early on, you can save your AC unit before it gets beyond repair.

Here are six problematic air conditioner noises and what they represent.

 1. The Air Conditioning Unit Makes a Humming Sound

Now, it’s fairly normal for most air conditioning units to produce a low-level hum. Let’s just say that, on the hierarchy of weird noises coming from your air con, it’d register pretty low. However, if your air conditioner is making uncharacteristically louder sounds than you’re used to, there’s likely an issue with a malfunctioning fan motor.

The motor can produce loud, strange noises when dust, dirt or debris block the fan blades or the motor itself is damaged. Should either of these be the case, we recommend calling a licensed technician for urgent air conditioner repair.

Even unblocking the fan requires access to the compressor’s internal components, and interfering with these may affect your air conditioning unit warranty.

2. Your Air Conditioner Makes a Buzzing Noise

It seems unlikely that a swarm of bees would set up shop within an AC unit. Therefore, if you’re hearing buzzing noises coming from your air conditioning system, it’s likely an electrical fault. The buzzing sound could indicate an electrical discharge from damaged or loose wiring. Given that this poses a significant safety risk and becomes a likely fire hazard, getting on top of the problem quick smart should be your priority.

Fast, decisive action with electrical faults in your air conditioner is a must. If you can, shut off the power to the air conditioner and call a heating, ventilation and air conditioning (HVAC) technician to resolve the issue. Catching the problem early could save on potential repairs down the track.

3. Clicking or Popping Noises from Air Conditioners

A single click or pop on start-up generally indicates that the air conditioner is communicating with the thermostat and is no reason for concern. However, if the clicking or popping noise doesn’t stop, then you might actually have a problem.

A defective relay or failing thermostat could be the culprit. Whatever the cause, it’s something you’ll need to replace, so check your warranty or call an air con technician for the appropriate fix.

In ducted air conditioning systems, differences in pressure between the air supply and the return duct can cause your popping or banging noise.

Another reason for noise can be the ducts expanding and contracting due to temperature changes. Having a professional clean the system, seal any leaks, and adjust the duct dampers can help reduce the noise.

4. A Squealing Noise from Your Air Conditioning Unit

An air conditioner may produce a high-pitched squealing noise. This often points to the blower fan belt in the motor having slipped and needing adjustment.

Thankfully, most modern air conditioner systems no longer use a belt system, so this problem is exclusive to older systems.

That being said, squealing noises aren’t exclusive to older air conditioners. Newer models can also produce a squealing noise if the bearings on the outdoor condenser unit have worn down from use or if the compressor fails. Both problems need to be addressed by a technician right away before they cause the motor to fail.

5. Your Air Con Makes a Rattling Noise

Rattling noises are among the most common of the undesirable loud noises you’ll hear from an air conditioner. There could be numerous possible reasons for it:

• Debris may have found its way into the system with the seemingly sole purpose of merely rattling and annoying.
• A loose component has broken off and now rattles around in the ducts or fan.
• If the outdoor compressor has experienced damage, you might find a bent fan blade that is now brushing the sides of the casing.

Whatever the cause, there’s a strong chance of the damage worsening. You’ll need to call a professional ASAP. They’ll likely provide a simple solution before you suffer further damage and need more extensive repairs or a full system replacement.

6. The Air Conditioner is Making Hissing Noises

If your noisy air conditioner produces a hiss, it could mean one of two things:

1. You have an air leak somewhere in the system, or
2. Your malfunctioning compressor has sprung a refrigerant leak.

Thankfully, an air leak is a relatively minor issue. By all means, certainly get it fixed. However, as a problem, it is more of an annoyance than a hazard.

The Dangers of a Refrigerant Leak

The greater concern is a refrigerant leak. All split systems and ducted air conditioners use refrigerant gases. They treat the air passing through the system to provide the desired heating and cooling.

Refrigerant leaks will restrict the cooling cycle of your air conditioning system. The gases also contain hazardous, toxic chemicals. Inhaling them opens up the possibility of health risks, while they can also act as a pollutant if released into the atmosphere.

If you hear a hissing noise or your air con doesn’t heat and cool like it used to, then it’s time to call an air conditioning professional. They’ll be able to seal the leak and perform an air con regas.

Noisy Air Conditioner Repairs

Minor noises can certainly be a normal part of your air conditioner’s operation. However, it pays to know that an unexpected screeching sound or grinding noise is doing more harm than good. Of course, the best way to prevent unusual noises from playing an unwanted symphony of sounds is to schedule a yearly air conditioner service.

A licensed HVAC system technician can provide maintenance by duct cleaning, inspecting, and regassing a system. This will help you to avoid common air conditioning issues and keep it performing at its best. A technician can also catch potential faults before they spiral into serious damage.

When you encounter one of these problematic noises, take it as a sign, and contact Metropolitan Air Conditioning 24/7 for emergency repairs and replacements. It’s the most effective way to enjoy the cold air you want during a blistering summer.

Please note: This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See our Terms & Conditions here.