7 Signs Your Aircon Needs Servicing Now
If you can spot any of these seven symptoms, the cost of servicing now is a fraction of the cost of letting it become an emergency call.
Quarterly servicing is the right cadence for most Singapore aircons — and most of these symptoms are early warnings that a routine visit or a fast aircon repair will clear before it turns into an expensive emergency. But aircons don’t always wait for the calendar.
Here are the seven symptoms we get most calls about, what each one usually means, and how urgent it is. For the full “how often” answer first, see our servicing frequency guide.
1. Warm air instead of cold
Urgency: high — book within 48 hours.
The unit runs, the fan blows, but the air coming out feels lukewarm or only slightly cool. The most common causes are a dirty filter (cheapest fix), a clogged evaporator coil (chemical wash), low refrigerant (gas top-up after leak test), or a failing capacitor (S$120 replacement).
A diagnosis takes 20–30 minutes and tells us exactly which of those is responsible.
2. Visible mould or dust on the louvres
Urgency: medium — book within 1–2 weeks.
Black or grey-green spots on the horizontal louvre vanes mean biofilm has grown through the fan coil and is now visible from the front. By the time it’s visible, the inside of the unit has 3–5x more buildup than what you can see.
Routine servicing might not be enough — a chemical wash usually is.
3. Musty smell when the unit starts
Urgency: medium — book within 1–2 weeks.
A faint musty or “wet socks” smell when the aircon switches on (and that fades after 5–10 minutes) is the early warning sign of biofilm in the drain pan or the back of the blower. Catching it early means a chemical wash (S$90) handles it; ignoring it for months means a chemical overhaul (S$160) is the only fix.
4. Water dripping from the indoor unit
Urgency: high — book within 48 hours.
Water at the front of the indoor unit, on the wall below it, or pooling on the floor almost always means a clogged drain pipe. The drain pan is overflowing because the pressure isn’t pushing condensate out fast enough.
A drain flush takes 15–20 minutes (S$80 if booked as a single-fault repair, included in routine servicing). Letting it continue can damage the wall, the unit’s drain pan, and any furniture below.
5. Louder-than-usual blower
Urgency: medium — book within 1–2 weeks.
A blower that has gone from “barely audible” to “noticeable” is usually a fan wheel that’s collected enough dust to throw it slightly out of balance. The motor is working harder than it should, which raises your bill and accelerates wear.
A blower wipe during routine servicing usually fixes it. If the noise is rattling rather than whirring, it can be a loose panel or a fan blade — different fix, but still routine.
6. Electricity bill jumped with no usage change
Urgency: medium — book within 2 weeks.
If your SP Group bill has gone up S$15+ per month with no change in your usage, the aircon is the most likely culprit. Dirty coils or low refrigerant force the compressor to work longer to deliver the same cooling, raising the kWh used.
A diagnosis (pressure check + visual on coils) takes 30 minutes per system and almost always identifies the cause.
7. Ice forming on the copper pipe outside
Urgency: high — book within 24 hours, switch off the unit until then.
White frost or ice on the smaller (high-pressure) copper pipe between the indoor and outdoor unit means the system is severely undercharged or the indoor coil is severely dirty. Continuing to run an iced system can damage the compressor permanently.
Switch off, message us, and we’ll diagnose the same day. The fix is usually a chemical wash + a leak test + a refrigerant top-up.
What most of these have in common
Five of the seven signs above (warm air, mould, smell, noise, ice) trace back to two root causes: biofilm buildup on the coil or low refrigerant. Both are caught by routine quarterly servicing in their early stage — much cheaper than waiting for the symptom to develop.
The two emergency-grade signs (water dripping, ice) are the ones to act on within 24–48 hours. The others can wait a week or two but shouldn’t be ignored beyond that.
Book a same-day diagnosis
If you’ve spotted any of these signs, WhatsApp +65 9182 5233 with the symptom and your postal code. We’ll quote a slot inside the hour during business hours and can usually get a technician on-site the same day for West Region addresses.