Switch it off and leave it off if...
It smells of burning, the breaker keeps tripping, water is running out of the indoor unit, or it's making a sound it never used to. Mitsubishi Electric says to stop using the unit in each of those cases, and to turn the breaker off for a burning smell. Leave the covers on and the wiring to a licensed technician.
What Sydney's weather does to an air conditioner
Western heat
Penrith averages 67 days a year above 30 degrees and reached 48.9 degrees on 4 January 2020. Mitsubishi Electric says that when it's very hot outside, a unit's cooling effect may not be enough, and that isn't always a fault.
Coastal humidity
January and February afternoons at Observatory Hill average 60% and 62% humidity. Mitsubishi Electric says running a unit for more than 4 hours in 80% humidity or more, or with windows open, can make condensation drip from the indoor unit.
Salt near the harbour and the surf
A corrosion guide based on AS 4312 rates the strip within 200 m of surf beaches as C5 (surf sea-shore) and harbour foreshores as C4 (calm sea-shore). Daikin's warranty card excludes damage to coils from salt air, so corrosion is often a repair you pay for.
Units on balconies and roofs
With 30.7% of Greater Sydney homes in apartment buildings, many outdoor units sit on balconies, roofs or high brackets. LG's warranty excludes the extra cost of reaching units in restricted or unsafe spots.
Checks to do before you book
Breaker, remote and mode
Check the breaker hasn't tripped and the remote has batteries and is on cool or heat. Samsung's tip: make sure a Timed Off or Sleep setting hasn't been left on.
The filters
Daikin says blocked filters can cut efficiency badly and calls cleaning them the most important maintenance you can do. If they're grey, clean them as your manual shows.
The outdoor unit
From the ground, clear leaves and anything stacked against it. Don't stand on it or climb up to a roof unit.
Give it time, and close up
Mitsubishi Electric's units wait about 3 minutes after a restart. Shut the windows and blinds on the sunny side, and remember a gas cooker running in the room adds to the load.
A fault, or a system at its limit?
A unit that still blows cold air but can't bring the room down on the hottest afternoon may be undersized for the house, or simply at its limit. One that blows room-temperature air, ices up, trips the power or drips inside has a fault. The first is a sizing conversation, perhaps about a bigger or extra unit; the second needs a repair.
Mitsubishi Electric says a unit that won't cool or heat may be leaking refrigerant. Finding and fixing the leak is the job: the ARC says topping up before the system's been tested and the leaks repaired is illegal. Our regas page explains why.
What makes a Sydney repair bigger or smaller
Access. A head above a stairwell, a unit on an apartment roof or a ducted unit in a tight roof space all add time.
Salt. Corrosion on a coastal coil or bracket can turn a simple fault into a parts job that the warranty won't cover.
Age. By Solar Victoria's reckoning, a system over 15 years old typically uses more than three times the energy of a modern reverse cycle one, so a big repair on an old unit is the moment to get a replacement quote too.
Warranty. Under warranty, the brand may decide who repairs it, so read the card before you ring anyone. The national air conditioning repairs page covers what the main brands ask.
Yours to try, and the technician's
You can
- Switching the unit off and catching drips while you wait.
- Writing down any error code and when the fault happens.
Leave to a licensed installer
- Opening the unit, clearing drains and replacing parts.
- Anything involving the refrigerant or the wiring.
- Units on roofs or out of reach from the ground.
Ask the repairer
- Is this a fault, or is the system undersized for this house?
- Is the coil or bracket corroded, and does my warranty cover that?
- If the refrigerant is low, where's the leak and how will you fix it?
- Do you hold an RAC01 licence and a NSW licence for air conditioning work?
- How long will the part take to arrive?
What we'd do
If it were our unit
We'd do the five-minute checks, then find the warranty card before ringing anyone. Out of warranty, we'd want a repair specialist who works on our brand to tell us in writing whether it's a fault or a size problem, because in a Penrith summer the two get mixed up. If the unit's old and the fault is big, we'd get a replacement quote alongside the repair.
