Common Aircon Problems

Aircon running but not cold? Tell blocked airflow, a refrigerant leak, compressor faults and room heat load apart by how cooling fades.

Aircon leaking water indoors? Tell a blocked drain from a freezing coil or sagging piping by whether the drip is steady, bursts, or moves.

Aircon won't turn on? Use what happens at startup to separate a broken supply, a lost handshake, a board lockout, and a dead start circuit.

Heat overload, a freezing coil, short cycling and unstable controls all stop a unit. The shutdown pattern is what separates the four here.

Aircon light flashing? Separate a safety-circuit trip, an indoor-outdoor signal fault, and a drifting sensor by blink pattern and runtime.

Vibration transfer, fan bearing wear and compressor strain sound different once the surroundings go quiet. What the pattern tells you here.

Aircon smells musty, sour, or burnt? Diagnose whether it's drain tray mould, deep coil buildup, or overheating wiring, and the urgency.

Breaker trips on startup? The trip timing, immediate versus after a brief hum, separates current leak, startup overcurrent, and heat damage.

Wiring heat, motor strain and board trouble each smell slightly different. What to check yourself, and which of them means stop right now.

One room stays warm while others cool fine? Tell a clogged unit, an indoor-unit fault, and a room heat-load problem apart by what you see.

Ice on your aircon pipe is real and fixable. Separate restricted airflow from a refrigerant leak by vent strength and where the ice sits.

A clogged filter, a slowing motor and ice on the coil all cut airflow. When it dropped, and how suddenly, is what tells you which one it is.

Indoor unit on, outdoor unit silent? Use the startup behaviour to separate a mode condition, a start-circuit fault, and a protection lockout.

A coil freezing, a drifting sensor and an outdoor unit dropping out all cycle. How the cooling fades, and what you hear, separates them.

Indoor unit on but no air? Tell a startup fan delay from a fan or PCB failure or frozen-coil protection by when the fan actually stopped.

Indoor unit getting loud? Use the sound type and timing to separate panel vibration, fan or blower wear, and drain or freeze-related water noise.

Aircon not cold after servicing? Tell weak airflow from a pre-existing fault or a post-service setup slip. The vent breeze is the first clue.

Aircon remote not working? Use the response pattern to tell a dead remote signal from a failed receiver or a command that cooling ignores.

Where it drips decides whether this matters at all. A drip from the outlet is there by design, and a drip from the pipe body is not at all.

Aircon louvre stuck while cooling still works? Tell a swing motor fault, linkage jam, and control signal apart by sound and stop point.

Fan stuck on one speed? Tell a dead command path from inverter mode logic from a fan drive fault by what the remote shows and you hear.

Aircon clicking? A single startup click is normal, repeated clicking points to a louvre stall, and rapid clicking signals a chattering relay.

Aircon vibrating or buzzing through the wall? Tell loose mounting, fan imbalance, and compressor strain apart by how it tracks fan speed.

Water on the pipes or trunking is sometimes normal. When sweating points instead to insulation, airflow or a cooling fault, and how to tell.

Stray infrared signals, a protective lockout and a failing board all beep, and they beep differently. Read the pattern to know which one.

Aircon trips only when several units run together? Tell circuit overload, a weak outdoor startup part, and earth-leakage apart by speed.

App commands do nothing? Separate a network or cloud drop, a WiFi adapter dropping the link, and a unit that takes the command but won't cool.

A smell that outlives a clean is telling you where it starts. How to separate room odour from deep contamination, and which cannot wait.

Outside moisture load, short run cycles and a fouled coil each leave a room sticky. How the damp behaves is what tells them apart here.

Aircon leaks only when it rains? Separate wall ingress, weather-pressure drain backflow, and rainwater near electrical points by timing.

One indoor unit trips the whole multi-split? Separate a local motor or board short, a humidity-driven insulation fault, and arc damage.

Outdoor fan spins but the room stays warm? Separate a compressor that won't load, gradual refrigerant loss, and a partial start command.

Normal auto-resume, an unstable supply and a weakened board all restart. The restart pattern is what separates one from the other two here.

Gurgling noise from your aircon? Separate harmless drain flow sounds from refrigerant path faults or water backup by the cooling trend.

Aircon hissing? Separate normal expansion noise, a refrigerant leak, and electrical arcing by timing, cooling trend, smell, and breaker.

Mist from your aircon? How long it lasts and whether cooling drops tells you if it's startup condensation, airflow imbalance, or coil icing.

Aircon slow to cool? Separate high room heat load, restricted airflow, and weakening system output by when it worsens and what stays normal.

Peak heat load, a fouled condenser and compressor strain all look like this. The weekly trend is what tells them apart from each other.

Fan keeps running after turning off? Separate the normal drying delay, a sticky fan relay, and an unstable mains supply by the pattern.

Airflow direction, a stuck louvre or fouled blower, and a whole-room output drop all read as uneven. What the pattern rules out for you first.

Aircon outdoor unit too hot to touch? Use the cooling pattern to tell normal heat rejection from condenser fouling or compressor overload stress.

Load sharing, flow imbalance and a fading compressor all show up this way. How fast one room recovers tells you which of the three it is.

Settled filter dust, a deeper coil problem and something unrelated all follow a haze spell. How to tell which one you are dealing with.

Aircon leaking after a service visit? Tell a loose drain connection from a capped line or open trunking insulation by where the water shows up.

Cooling fades again after every gas top-up? Tell an open joint from a concealed pipe leak or a fouled condenser by what the outdoor unit shows.

Outdoor unit noisy only in wind or after a storm? Tell trapped debris from a closing fan clearance or loose mounting by when the noise stops.

A rocking outdoor unit, a loose fan part and a worn bearing all announce themselves at startup. How it began tells you which one it is.

Serviced on schedule and still cooling worse? Tell deep coil fouling from a wrong service interval or lost airflow by what the coil looks like.

A low point refilling, a crushed section and a cracked pipe all return. How quickly it came back is what separates the three from each other.

New aircon never cooled properly? Tell a charge never sized for the pipe run from air left in the line or a mode left on after handover.

One room warm since a renovation? Tell a blocked supply path from a blocked return or a zone sensor left elsewhere by the airflow at the vent.

Aircon faulting since renovation works? Tell a rejoined signal wire from a nicked cable or renovation dust by whether the error is constant.

Aircon only noisy at one fan speed? Tell a grazing fan blade from a duct whistle or a chattering cover by whether you can stop it by hand.

Aircon breaker tripping only in wet weather? Tell a perished isolator seal from a missing grommet or a loose terminal by when it started.

Aircon only drips sometimes? Tell a hairline joint gap from a narrowed line or a slowing drain pump by when the water actually appears.

Every aircon unit stopped at once? Tell an outdoor board failure from a lost power supply or an outdoor unit at end of life by the error shown.

Aircon noisier or weaker since its service? Tell an off-centre blower from a loose panel or an unclipped filter by whether airflow also dropped.

Aircon dead since its service visit? Tell an isolator left switched off from a board that lost its state by whether any lights come on.

Breaker tripping only since your aircon was serviced? Tell an under-tightened terminal from a cover left open by when the trips happen.

Aircon only struggles when it is hottest? Tell a weakening run capacitor from worn cable insulation by whether it starts fine on mild days.

Water on your aircon trunking can mean pipe sweat, a cracked drain fitting, or a shifted drain slope. Which sign points to which cause.