When the weather turns hot and humid in Sydney, most homes rely heavily on cooling systems. So when you suddenly notice water pooling under your indoor unit or dripping down your wall, it’s natural to ask: why is my aircon leaking water?
A leaking unit is one of the most common issues reported across residential air conditioning repair Sydney services. Sometimes it’s a simple maintenance problem. Other times, it’s a sign that your system needs urgent attention to prevent electrical damage, mould growth, or complete system failure.
Below, we break down why your air conditioner is leaking water, the common air conditioner water leak causes, and what you can safely do before calling an aircon technician Sydney.
Why Is My Air Conditioner Leaking Water? Common Causes Explained
1. Blocked Drain Pipe or Condensate Drain
One of the most frequent reasons homeowners ask why is my air conditioner leaking water is a blocked drain pipe. Dust, dirt, and algae build-up can clog the aircon condensate drain, causing water to back up and overflow. This often leads to aircon leaking water inside, especially in split systems.
When the aircon drainage problem is severe, the water may start dripping down the wall or onto your floors, creating a slipping hazard and potential wall damage.
2. Dirty Filter Restricting Airflow
A dirty air conditioner filter causing leaks is more common than you might think. When a filter becomes clogged, airflow is restricted, and the evaporator coil can become too cold. This leads to a frozen evaporator coil, which eventually melts and causes excess water runoff.
If you’ve ever wondered why is my split system air conditioner leaking water, a dusty filter is often the culprit—especially during the peak of summer.
3. Low Refrigerant Levels
Low refrigerant reduces cooling efficiency and also increases condensation buildup. This can lead to aircon dripping water or water overflowing the condensate tray. If you notice hissing sounds or your system isn’t cooling well, this could be the cause.
4. Installation or Level Issues
Poor installation or an uneven indoor unit can make water pool in the wrong areas. For example, a tilted drain pan may cause water coming out of your air conditioner unexpectedly. If the system was installed recently, ask your installer or reach out to a professional to re-check the levels.
For new systems, ensure they’re installed correctly:
👉 Air Conditioning Installations Sydney
Why Is My Aircon Leaking Water Inside or Outside?
Leaking Inside
If you’re seeing aircon leaking water inside, the issue is usually related to:
A blocked condensate drain
Frozen coil melting
Dirty filter
Airflow issues
High humidity causing excess condensation
Sydney’s coastal climate can lead to air conditioning moisture problems, increasing the likelihood of indoor leaks.
Leaking Outside
When homeowners ask why is my aircon leaking water outside, the answer is usually less alarming. Some water outside is normal due to condensation. However, excessive dripping could indicate:
Refrigerant issues
Blocked outdoor drainage
A strain on the cooling system
If unsure, it’s always safer to book same day aircon repair Sydney to avoid unexpected breakdowns.
Should I Turn Off My Aircon if It’s Leaking Water?
Yes—if your system is leaking, it’s best to turn it off. Continuing to run it can worsen the HVAC water leak, cause electrical hazards, and risk internal damage.
Many homeowners ask: can a leaking aircon cause damage?
Absolutely. Water can harm walls, flooring, wiring, and insulation, and can trigger mould growth—especially in humid Sydney homes.
If the leak is severe or sudden, contacting an emergency aircon repair Sydney service is the safest option.
How to Fix Aircon Leaking Water (And When to Call a Pro)
DIY Steps You Can Try Safely
You can attempt the following:
Clean or replace a dirty filter
Check for visible blockages in the drain pipe
Ensure the outdoor unit isn’t obstructed
Allow frozen coils to thaw completely
If after doing this you still wonder why is my aircon leaking water, you’re likely dealing with a deeper system issue such as:
A damaged drain pan
Refrigerant imbalance
Faulty installation
Internal mechanical faults
These require professional attention from a licensed aircon technician Sydney.
Local Focus: Aircon Leaking Water Sydney – When to Call a Technician
If you notice:
✔ Continuous water leaking
✔ Strange noises
✔ Warm air blowing
✔ Strong smells or mould growth
✔ Water coming out of the air conditioner unexpectedly
…it’s time to call a specialist.
Sydney homeowners—especially those with older split systems—often face cooling system drainage issues, condensate tray overflow, and blocked aircon drainage problems.
Innovation Air Conditioning provides residential air conditioning repair Sydney and can inspect and fix leaks quickly to prevent long-term damage.
Helpful .gov Resources About Cooling & Safety
NSW Fair Trading – Air Conditioning & Home Repairs Guidance
https://www.fairtrading.nsw.gov.au/Australian Government – Energy.gov.au: Heating and Cooling Efficiency Tips
https://www.energy.gov.au/
These resources offer consumer safety guidelines and maintenance advice for keeping your air conditioning system efficient and safe.
Still asking why my aircon is leaking water? Don’t wait until the leak becomes a costly repair.
Innovation Air Conditioning provides fast, reliable air conditioning leak repair, split system air conditioning service in Sydney, and professional maintenance to keep your system running smoothly year-round.