Common aircon faults
The problems we hear about most, what usually causes them and what you can safely check before you call. A symptom alone does not establish the cause. The unit needs to be assessed before a repair is agreed.
Aircon running but not cooling
Signs: The fan blows but the room does not cool down, or it takes much longer than it used to.
Common causes: Dirty filters, a blocked or dirty outdoor unit, low refrigerant from a leak, or a compressor, fan or sensor fault.
What to check: Check the remote is on Cool and set below room temperature, clean the filters, and make sure the outdoor unit is running and clear.
Aircon blowing warm air
Signs: Air comes out at room temperature or warm when it is set to cool.
Common causes: The outdoor unit is not running (power, capacitor or compressor fault), the wrong mode, or low refrigerant.
What to check: Check the mode, then look at the outdoor unit. If its fan is not turning, switch off and call.
Aircon leaking water
Signs: Water drips or runs down the wall under the indoor unit.
Common causes: A blocked or disconnected drain pipe, a coil that has iced up because of dirty filters or low refrigerant, or poor drainage from the installation.
What to check: Switch the unit off to protect the wall and electrics, and clean the filters. Do not keep running it while it leaks.
Aircon making a noise
Signs: Rattling, buzzing, clicking, squealing or a loud hum from the indoor or outdoor unit.
Common causes: Loose panels or mountings, a worn fan motor or bearing, debris in the outdoor unit, or an electrical fault.
What to check: Switch off if the noise is loud or grinding, or if there is a burning smell.
Aircon won't switch on
Signs: Nothing happens when you press the remote, or the lights flash and it stops.
Common causes: Remote batteries, a tripped breaker, a wiring or control board fault, or a safety shut-off.
What to check: Replace the remote batteries and check the breaker. If it trips again, leave it off and call.
Error code or tripping the power
Signs: The display shows a code, or the unit trips the breaker or isolator.
Common causes: Sensor, fan, compressor or electrical faults. The code points to the area to investigate.
What to check: Note the brand, model and the code shown, and include them in your enquiry.
Bad smell from the aircon
Signs: A musty, damp or burning smell when the aircon runs.
Common causes: Dirt and mould on the filters and coil, a blocked drain, or an electrical fault in the case of a burning smell.
What to check: For a burning smell, switch off at the isolator straight away and call.
Ice on the pipes or indoor unit
Signs: Frost or ice on the copper pipes or inside the indoor unit.
Common causes: Very dirty filters restricting airflow, a fan problem or low refrigerant.
What to check: Switch off and let it thaw, clean the filters, and call if it ices up again.
Safety first: do not open the unit, touch the wiring or try to re-gas it yourself. Switch off at the isolator if you smell burning, see sparks or the unit keeps tripping.
How a repair works
- Tell us the fault: brand, model if known, what it is doing and your suburb.
- Confirm costs: ask about assessment and call-out costs before the visit.
- Diagnose: the unit is checked to find the cause.
- Quote and repair: agree on the repair cost, including parts, before the work goes ahead.
Aircon servicing
Many breakdowns start with dirty filters and a unit that has not been serviced. Clean the filters every few weeks when the aircon is in use, and book a service at least once a year, ideally before summer. A service helps the unit cool properly, use less electricity and last longer.