Still not cold after the checks? Text us your suburb, the size of the system and what it’s doing. Our automated quote assistant replies straight away, at any hour.
An air conditioner not cooling is most often caused by a blocked filter, the wrong setting on the remote, a blocked outdoor unit, a tripped breaker or low refrigerant from a leak. The first four you can check yourself in a few minutes. Ice on the coil, a leak, a still outdoor fan or a breaker that trips twice need a licensed technician.
The quick answer
- Start with the remote: Cool mode, a set temperature below the room temperature, and no timer or sleep mode running.
- Dirty filters cut airflow and efficiency. Wash them and try again.
- A split system is sealed, so low gas means a leak. Only a licensed technician can handle refrigerant.
- A service and clean is $341 including GST for one unit. A regas after a leak check is $709.50 or $854.50 including GST.
Why is my air conditioner not cooling?
Match what you’re seeing to the likely cause. The last column tells you when it stops being a job for you.
| What you notice | Likely cause | Call a licensed technician when |
|---|---|---|
| Weak airflow, air only slightly cool | Dirty filter or coil | Airflow is still weak with clean filters |
| The room never feels right | Remote on Dry, Fan or Auto, or a timer on | The settings are right and it still won’t cool |
| Cooling fades on hot afternoons | Blocked outdoor unit | It’s clear and still cuts out |
| Nothing starts | Tripped breaker | The breaker trips a second time |
| Ice on the coil or pipes | Restricted airflow or low refrigerant | Straight away |
| Cool but never cold, hissing | Refrigerant leak | Straight away |
| Room temperature air, outdoor fan still | Failed capacitor or fan motor | Straight away |
Four checks you can safely do yourself
These four fix plenty of not cooling problems without a visit. None of them involves opening the system.
- Check the remote shows Cool, not Dry, Fan or Auto, with the set temperature below the room temperature. Turn off any timer or sleep mode, and change the remote batteries if the display is faint.
- Take the filters out of the indoor unit, wash them, let them dry fully and refit them.
- With the system off, clear leaves, pot plants and stored items away from the outdoor unit so air can move through it.
- Look at the switchboard. If the air conditioner’s breaker has tripped, reset it once. If it trips again, leave it off and call us.
The Australian Government’s Energy Rating heating and cooling page says dirty filters significantly reduce airflow and the energy efficiency of the unit. It suggests running the system between 25 and 27 degrees in summer to save money.
Clean filters, still weak? It could be the coil
The coil sits behind the filters. When it’s coated in dust or mould, air can’t pass through it properly, and washing the filters won’t fix that. A musty smell when the system starts is another sign.
A coil and drain clean is part of our air conditioning service in Brisbane. A service and clean is $341 including GST for one unit and $577.50 for two. For a heavier clean, see our air conditioner cleaning in Brisbane page.
Ice on the coil is a symptom, not the fault
Ice forms when the coil runs too cold. That happens when airflow is restricted, by a blocked filter or a failing indoor fan, or when refrigerant is low. The ice then blocks the coil, so warm air passes straight through.
Seeing ice? Turn the system off and let it thaw. Never chip at the ice or pour hot water on the coil. If it comes back with clean filters, call a technician.
Does your air conditioner need regassing?
A split system doesn’t use up its gas. The refrigerant moves around a sealed loop, so a system that is low has a leak. Gas added without fixing the leak will leak out again.
The Australian Government states that it is an offence for anyone other than a licensed technician to handle fluorocarbon refrigerants, and that it’s illegal to release regulated refrigerants into the air. The source is the Department of Climate Change, Energy, the Environment and Water page on refrigeration and air conditioning for consumers. Our ARCtick licence is L181564.
A regas after a leak check is $709.50 including GST for 2 to 3.5 kW and $854.50 for 5 to 8 kW. Our aircon regas cost guide explains why the leak check comes first.
Text for a quote Call 07 4428 2766
When the outdoor fan won’t spin
If the indoor unit blows room temperature air and the outdoor fan is still, or the outdoor unit hums and clicks, the fault is usually a failed capacitor or fan motor. A capacitor can hold a charge after the power is off, so this is a job for a licensed technician, not a home repair.
Before you call, note down
- Any fault code or flashing light on the indoor unit.
- Whether the outdoor fan spins.
- Whether the breaker has tripped, and how many times.
Our air conditioning repairs Brisbane page explains how a repair visit runs, and our Logan page covers air conditioning repairs in Logan. We repair split systems. We service and clean ducted systems, but we don’t repair them.
Working, but too small for the room
Sometimes nothing is broken. The air coming out is cold, the outdoor unit runs, but the room never reaches the set temperature on a hot afternoon. That points to a system that is too small for the room, and a repair won’t change it.
Our guide on what size air conditioner you need covers room size, sun and ceiling height. A new 5.0 kW split system, supplied and installed, starts from $2,414.50 including GST.
Common questions about an aircon that won’t cool
Why is it blowing air but not cold air?
The fan works but the cooling side doesn’t. Check the mode on the remote and the filters first, then whether the outdoor fan is spinning.
Can I regas it myself?
No. Only a licensed technician can handle refrigerant, and the leak has to be found before any gas goes in.
Is the quote free?
Yes. The written quote is free, and the quoted price is the invoiced price.
Our advice
Check the remote, the filters, the outdoor unit and the breaker first. If it still won’t cool, start with a service and clean at $341 including GST, because a dirty coil causes the same weak cooling as low gas. Ice, hissing or a still outdoor fan means it’s time to call a licensed technician.
Get your air conditioner cooling again
Text us your suburb, the size of the system and what it’s doing. Our automated quote assistant replies straight away, at any hour.
Text for a quote Call 07 4428 2766
Calls are answered Monday to Friday, 7am to 3:30pm. Or send the details online.
Prices current as of 5 October 2026 and include GST. Sources: Energy Rating (Australian Government), “Heating and cooling”; Australian Government, Department of Climate Change, Energy, the Environment and Water, “Refrigeration and airconditioning, consumers”. This article is general information. It is not advice about your system.
Related guides
How to Prevent Air Conditioner Short Cycling
Air Conditioner Replacement Cost Brisbane: 7 Key Factors
Air Conditioner Installation Price Brisbane 2026: What to Expect- Split System Brands Compared for Brisbane Homes 2026
- Air Conditioner Running Cost Calculator: AU Guide
All guides: electrical and air conditioning guides.
Licensed electricians and ARCtick refrigeration technicians, Queensland Electrical Contractor Licence 90552 and ARCtick L181564. We install and service split systems and do the electrical across Logan, Brisbane southside, Ipswich and the northern Gold Coast.
About Faze | Call 07 4428 2766 | Text 0489 275 747