That telltale puddle under your indoor AC unit isn’t just annoying – it’s a warning sign of deeper issues. In Malaysia’s humid climate, AC leaking causes mold growth, ceiling stains, and even electrical hazards. After troubleshooting thousands of units, I’ve identified these 5 real culprits behind leaks and how to fix them fast.
1. Clogged Drain Lines: The Silent Flood Starter
What happens:
Dust + humidity = slimy algae that blocks drainage pipes. Water backs up until it overflows. Learn more (How to Fix Clogged AC Drain Pipe)
Malaysia-specific triggers:
- Construction debris in urban areas
- High pollen counts during dry seasons
- Tiny insects breeding in moist pipes
DIY Fix:
- Pour 1 cup warm vinegar down drain access point
- Wait 20 minutes
- Flush with 500ml boiling water
- Repeat monthly during rainy season
Red Flag:
If water flows slower than 1 liter/minute, call for Air conditioning service – deep blockages need vacuum extraction.
2. Frozen Evaporator Coils: The Iceberg Effect
Why coils freeze:
- Dirty filters (blocks airflow)
- Low refrigerant (causes temperature plunge)
- Faulty blower motor
The leak chain:
Ice forms → AC shuts off → Ice melts → Drain pan overflows
Emergency Response:
- Turn off AC immediately
- Let coils thaw naturally (6-8 hours)
- Replace filters
- If frost returns, seek professional diagnosis
3. Cracked Drain Pans: The Aging Weak Spot
Common in units 5+ years old:
- Plastic becomes brittle from chemical exposure
- Rust eats through metal pans
- Accidental damage during cleaning
Spot the signs:
- Rust-colored water stains
- Leaks from unit corners
- Visible cracks when removing front panel
Solution:
- Temporary patch: Silicone sealant
- Permanent fix: Pan replacement (RM150-300)
“Units with poor initial workmanship often need early pan replacements. Always choose quality aircon installation kl providers with stainless-steel components.”
4. Improper Unit Leveling: The Gravity Fail
How it causes leaks:
Water flows sideways instead of toward drain
Malaysian homes suffer from:
- Foundation shifts in clay soil areas
- Poor initial installation
- Wall sagging in older buildings
Quick Check:
Place marble on indoor unit → If it rolls sideways, relabeling needed
Fix:
- Adjust mounting bracket screws
- Use laser level for precision
- Ensure 1cm downward slope per meter toward drain
5. Refrigerant Leaks: The Invisible Thief
The sneakiest cause:
- Pinhole leaks in copper pipes
- Faulty Schrader valves
- Corroded joints
Why it overflows drains:
Low refrigerant → Evaporator coil freezes → Meltwater overloads pan
Danger signs:
- Hissing sounds near outdoor unit
- Oil stains on pipes
- AC runs constantly but cools poorly
Urgent action required:
- Shut off system immediately
- Contact licensed technician (refrigerant handling is illegal for DIY)
- Expect RM200-500 repair depending on leak location
Prevention Toolkit for Malaysian Homes
| Problem | Prevention | Frequency |
| Clogged drains | Vinegar flush | Monthly |
| Frozen coils | Filter replacement | 8 weeks |
| Cracked pans | UV light installation | Once |
| Level issues | Bracket inspection | 6 months |
| Refrigerant leaks | Pressure testing | Yearly |
When DIY Fails: Professional Rescue Signals
Call for backup if:
⚠️ Water flow doesn’t improve after 2 vinegar flushes
⚠️ You smell ammonia (indicates hazardous refrigerant)
⚠️ Leaks persist after 48 hours of troubleshooting
⚠️ Mold appears on walls/ceilings
“For complex leaks in high-rise buildings, trusted aircon services Malaysia teams use pipe cameras to pinpoint hidden blockages.”
FAQ: Leak Emergencies
Q: Is brown leakage water dangerous?
A: Likely rust from drain pan – clean immediately to prevent staining.
Q: Why does my AC leak only at night?
A: Lower temperatures increase condensation – usually indicates partial drain blockage.
Q: Can I use drain cleaners from supermarkets?
A: Avoid! Most contain acids that corrode PVC pipes.
Q: How much does professional leak repair cost?
A: RM120-350 depending on cause (drain clean vs. refrigerant repair).
Q: Will my insurance cover water damage?
A: Only if caused by sudden failure – gradual leaks are excluded.