An aircon should run quietly in the background, not announce itself. If yours is making noise it didn’t used to, here’s what each sound usually means.
Buzzing
Often points to a faulty component, condenser coil issue, or a refrigerant leak. Since several different causes produce a similar buzz, this one needs a technician to actually identify the source rather than guess.
Clicking
A brief click when the unit switches on or off is normal. Continuous clicking throughout operation usually means a faulty control component and is worth getting checked before it worsens.
Banging
Almost always a loose or broken internal part. A banging sound means something has come loose inside the unit and needs inspection soon, not eventually.
Squealing
Often a sign of wear, sometimes related to airflow through the duct system or a belt-driven component starting to fail. Worth checking before it becomes a bigger mechanical issue.
Humming
A faint hum during normal operation isn’t unusual, but a noticeable hum can point to a faulty part, a refrigerant issue, or an electrical wiring problem. If it’s new or getting louder, don’t ignore it.
Clanking
Usually a loose or misaligned internal part, sometimes the compressor itself. This one tends to get worse quickly, so it’s worth addressing early rather than waiting to see if it settles.
Screaming or High-Pitched Whistling
Often linked to compressor or refrigerant problems. This is one of the more serious noises on this list and should be treated urgently, both for the unit and for safety.
Rattling
Usually loose bolts, screws or components that are starting to wear. A quick visual check inside the unit sometimes reveals the cause, but a proper inspection catches it before parts fail completely.
How Urgent Is It?
Clicking and humming are usually the least urgent, though still worth a check if new or worsening. Buzzing, squealing and rattling call for attention soon. Banging, clanking and screaming are the most serious and shouldn’t be left running while you wait. If you’re not sure which category your noise falls into, book a repair rather than guessing.
Could Regular Servicing Have Prevented This?
Often, yes. Most of these noises trace back to wear that regular servicing catches early, loose components, worn parts, or refrigerant issues, before they turn into an audible problem. If your unit has been running noisy for a while, it’s also worth a chemical wash to rule out buildup as a contributing factor.
FAQs
Is it safe to keep using a noisy aircon?
For clicking or mild humming, usually. For banging, clanking or screaming, switch it off and get it checked rather than continuing to run it.
Can noise indicate a refrigerant leak?
Yes, particularly buzzing, humming or screaming. If you also notice weaker cooling, that’s a strong sign of low refrigerant.
Will the noise go away on its own?
No. Whatever’s causing it, whether a loose part or a developing fault, needs to be addressed directly.
How fast can you diagnose a noisy aircon?
Same-day slots are available across Singapore. WhatsApp us a description (or a short video) of the noise and we’ll advise before you book.
