What are the most common split system aircon problems?

  • air conditioning installation for builders

Split system AC makes up the lion’s share of the air conditioning in Brisbane – and it’s little wonder! These systems are:

  • Versatile
  • More affordable up-front
  • Quick to install

As you can see, there are plenty of advantages of installing a split system.

Of course, just like their bigger ducted cousins, split system installation isn’t the end of the story – it’s crucial that you keep your system well-maintained and stay on top of air conditioning problems as well.

Air conditioning service and repair are crucial to keeping your system running – and by extension, keeping your home nice and comfortable.

Fail to do so, and you might find yourself running into any number of problems…

What are common problems of split system aircon?

Unfortunately, we can’t give a straight answer to this one – air conditioners (even split systems) are complicated pieces of equipment, with lots of moving pieces.

And that means there are a lot of places where something can go wrong.

That said, there are a couple of issues that tend to pop up more than others…

Weak airflow

When you turn your split system on, you expect a blast of cool air.

Unfortunately, a number of problems can stop this from happening, leaving you with weak airflow and a home that’s swelteringly hot!

This includes:

  • Clogged filters
  • Frozen evaporator coils
  • Leaky or blocked tubing
  • Low refrigerant levels

Whatever the cause, the result is the same: less comfort and a higher power bill as your system works double-time to pick up the slack.


Moisture, darkness and something to “eat” – these are the three key ingredients to mould growth.

Your split system is already home to the first two – over time, debris can build up, creating the third and final ingredient.

Mould is a surprisingly common issue in split systems – luckily, it’s one that can be fixed with an air conditioning clean-out.

Failure to turn on

In addition to all of the piping and refrigerants, split system air conditioners also include all manner of electrical components and wiring.

In many cases, the electrical components responsible for turning your system on in the first place can be affected, with loose connections and frayed wires.

Luckily for you, our team is also licensed to fix electrical faults such as this, ensuring your system turns on like it should when you press the button on the remote!

Thermostat not working

The thermostat is another important electrical component in your split system air conditioner. 

Should it fail, your system might not be able to signal the system to turn on, or it might not be able to accurately gauge the indoor temperature, affecting its cooling power.

Once again, our team can fix faulty electrical components, including issues with your system’s thermostat.


How do you troubleshoot a split AC unit?

There are a number of issues that you might face with your split system – diagnosing and troubleshooting these issues will depend on the exact issue your system is facing.

We can’t go through all of them – however, we can discuss some of the more common ones…

Why is my AC running but not cooling?

It’s blowing out air. Just one problem: it’s lukewarm.

In these cases, there are two main culprits:

  1. The compressor is dirty or blocked
  2. You’ve run out of refrigerant

The first is pretty easy to troubleshoot – just take a gander to your outdoor unit, shine a torch into it and check how it looks.

As for the second however, it’ll depend on your system. Some actively monitor refrigerant levels, allowing you to check using the thermostat or remote. If yours doesn’t do this however, you’ll need to contact a professional.

How do I know if my AC fuse is blown?

Faulty thermostats and loose wiring aren’t the only sorts of electrical issues that can affect your split system.

Fuses and switchboards are installed in every house to protect you. Once they detect a power surge or short circuit, they trigger, cutting off the flow of power just to be safe.

You’ll know that this is what’s causing your problem by checking your switchbox if you notice your system not working properly. If the switches or fuses have been triggered, then it’s pretty safe to assume this is the issue.

Air conditioning service and repair

Can split AC be shifted?

This isn’t quite an operational problem; it’s all to do with system design. Namely, the lack of design or consideration at the pre-installation stage, which has left you with a split system in a less-than-optimal position.

If you’ve noticed that your system isn’t giving you the comfort you want, the issue may not be with the system itself. Instead, the problem could be where it’s been installed.

This is why the system design process is so important – it’s the little things that affect comfort, after all. Choosing the wrong spot for your system can mean that air isn’t flowing as it should, or that parts of your home are being cooled unevenly.

Luckily, it’s entirely possible to move your system!

Say your original installer chose a suboptimal position. Alternatively, it could be the case that you want to make use of the wall your system is currently installed on, and would like it moved to make that happen.

Air conditioning relocation involves a number of steps:

  1. Dismounting your wall-mounted unit
  2. Plugging the hole left behind
  3. Mounting it in its new location
  4. Running supply tubes to and from the outdoor unit

And it isn’t just the indoor unit we can move, either – in some cases, we’ve been asked to move outdoor units to clear space, adhere with council heritage restrictions and more!

Good system design helps you avoid these problems to begin with

All too often, air conditioning installers will just choose whichever spot is most convenient from an installation perspective.

In doing so, they can often choose a less-than-ideal spot, forcing you to shell out money to get your split system shifted later!

During system design, we look at many things, such as power, room volume, including the best place on your wall to ensure maximum airflow.

Location is just one of the things we look at during system design – we’ll also answer questions such as:

Thinking about a new system? If so, you’ll need to choose someone who you can trust to carry out the installation properly – including in-depth system design.

Air conditioning service in Brisbane (and beyond)

Whichever one of these issues you run into with your split system air conditioner, it’s important that you get a professional to look after it for you.

Air conditioning systems are complex machines that can’t be fixed with DIY repairs, especially if your system is facing a deeper issue. You need a specialist for aircon service in Brisbane!

What’s more, it’s just as important if not more so that you choose someone who can come to you quickly – Brisbane can get awfully hot in summer, after all.

Based in south Brisbane (Morningside, to be specific) our team of air conditioning experts are able to get to you quickly, cutting down the amount of time you spend sweltering in the hot summer heat.

Our team works across Brisbane, and can even service systems outside of the city too – our commercial air conditioning team offer installation and ongoing service to businesses in:

  • Logan
  • Gold Coast
  • Caboolture
  • Ipswich

Got a problem with your split system A/C? Want to learn more about our air conditioning finance options? Interested in the advantages of split over ducted?

Whatever you’re interested in, our team is ready to answer the call – give us a ring today on (07) 3394 0222, or click here to get in touch online.

2023-08-18T06:31:42+00:00 4 February 2021|Installation, Service, Systems|