Aircon Problem Super Guide: 25 Common Faults Explained
- thesnowflakesg
- Feb 2, 2022
- 4 min read
Updated: 3 days ago
Aircon acting up? Not cold, leaking water, strange smells, loud noise, or flashing errors?
This guide helps you understand what your system is actually telling you — before you waste money on the wrong fix.
It’s not a DIY repair manual. It’s a field-tested breakdown of 25 common faults we’ve seen across thousands of visits — in homes, offices, clinics, and shops.
Your system is sending a signal.
Start here, and know what to do next.
Cooling & Airflow Failures
1. Not cold / airflow weak
2. Recently serviced, still not cold
3. Only some rooms are cooling (multi-split)
4. Feels cold, but room still warm
5. Room never reaches set temperature
Leaks, Moisture & Drainage
6. Water leaking from indoor unit
7. Water backing out from drain pipe
8. Leak only happens after shutdown
9. Condensation on trunking or wall
10. Wall wet near piping
Smell, Mold & Hygiene Signals
11. Musty smell after cooling stops
12. Smell during use (musty, sour, burnt)
13. Smell is clean, but airflow is weak
14. Burning smell on startup
Noise & Outdoor Unit Behaviour
15. Indoor unit rattling or vibrating
16. Grinding or buzzing noises
17. Outdoor unit louder than usual
18. Humming, but no cooling
Controls, Errors & Communication Faults
19. Blinking lights or flashing error code
20. Remote not working despite battery change
21. Unit turns on and off repeatedly
22. Room temperature reading seems off
Startup & Electrical Failures
23. Unit won’t power on
24. Turns on, but no airflow
25. Starts, then shuts off after a few minutes
Need aircon help?
Whether it's cooling issues, leaks, noise, or weak airflow — we diagnose first before recommending any fix. No guesswork. No pressure. Just proper checks and real solutions.