Air conditioners work by removing moisture from the air. It’s normal to have a small amount of water. However, water leaking inside your home is usually a sign that something isn’t working correctly.
Water is a homeowner’s worst nightmare. If left untreated, it can quickly turn into discolouration, damage, and even rot. Excessive water leaking from an air conditioning (AC) unit is rarely a good sign.
The cause isn’t always straightforward. It could be due to a simple maintenance issue or a component failure. We cover the most common causes and solutions.
Why Is My Air Conditioner Leaking Water?
Why your air conditioner is leaking isn’t always one simple issue, your air con could be leaking due to:
Blocked Condensate Drain Line
By far the most common cause. Dust, dirt, algae, and debris can block the drain, causing water to back up and leak from the unit.
Dirty Air Filter
Air conditioners rely on the flow of water between the inside and outside of the unit. Restricted airflow caused the internal temperature to plummet, freezing the evaporator coil. When the ice melts, excess water can overwhelm the drainage system.
Damaged or Rusted Drain Pan
Common in older systems. Cracks or corrosion can allow some water to escape.
Frozen Evaporator Coil
Usually linked to poor airflow or refrigerant issues. As mentioned, when the ice melts, it can overwhelm the drainage system, causing water to leak out.
Incorrect Installation
One of the most underrated causes. AC units must be properly levelled. If they’re not, the drainage system won’t work effectively. Water begins to pool until it overflows.
Does AC Dripping Indicate a Bigger Problem?
Not always. External dripping can often be normal condensation. Think of a cool glass of water on a warm day. There’s no water dripping out of the glass, but water from the air still settles on the surface.
Internal leaking is a different matter entirely.
Usually, excessive leaks are caused by something going wrong inside the AC unit. The water will inevitably leak out, running down the wall and causing mould and water damage. Even if the damage hasn’t yet set in, reduced efficiency can spike your energy bills.
Can I Still Use My Air Con If It’s Leaking?
That depends. If you’ve got a blocked line, a continually running AC unit will only cause more water to leak out. In contrast, a mildly blocked air filter probably won’t cause catastrophic issues. Most external condensation won’t cause any issues; however, it’s sensible to look for mould periodically.
Just remember that continued use could worsen damage. For example, if water builds up within the system, it could damage electrical components, permanently breaking the AC unit.
How Do I Stop My Air Conditioner From Leaking Water Inside?
If your air conditioner is leaking water indoors, start by taking a few basic troubleshooting steps:
- Turn the system off.
- Check and replace the air filter if it’s dirty.
- Inspect any visible drain lines for blockages.
- Look for obvious signs of debris or standing water.
- Clean around the indoor unit.
If the leak persists, it’s time to call in the professional. Don’t attempt DIY repairs of refrigerant lines or electrical components. You’re likely to do more harm than good.
Will Turning Off the AC Stop It From Leaking Water?
Yes and no.
Turning it off may temporarily stop water production, especially if the cause is a blocked drainage pipe. That said, existing ice may continue to melt, temporarily causing more water to leak.
Either way, it’s smart to turn off your AC unit during a leak as a temporary precaution. You can then inspect the unit to try to identify the underlying problem.
How to Fix an Air Conditioner Leaking Water Inside Your Home
The correct repair depends on the cause. If the problem is a blocked air filter, the solution is relatively simple: change the dirty filter. The same is true if you’ve got a damaged drain pan.
However, anything like a blocked condensate drain, refrigerant issues, or cleaning evaporator coils is best left to a professional. Unless you’ve got prior experience, it’s very easy to break something accidentally.
Preventing Future Air Con Leaks
Where most people can make a difference is in preventing future leaks. Scheduling a regular service is the smartest option. The repair person can identify any issues in advance, preventing leaks and potentially saving you money.
They’ll also change the filters and clean the drain lines: the two most common causes of leaks. Together, they help extend the lifespan of the air conditioning unit.
Need Help With a Leaking Air Conditioner?
No one wants to ignore water leaking for long. Usually, it indicates something isn’t working as it should.
Premium Heating & Plumbing Cooling provides professional air conditioning servicing, maintenance, and repairs. Whether you need a blocked drain cleared, a faulty component replaced, or a full system inspection, our experienced engineers can quickly identify the problem and get your system back up and running.
Contact our team today to book an air conditioning inspection.
Read Next: What to Do If Your Air Conditioning Unit Is Blowing Warm Air
Frequently Asked Questions
Can an AC Water Leak Cause Fire?
Generally, no. A water leak alone is unlikely to cause fire damage. However, if water comes into contact with electrical components, it can cause safety hazards.
Is AC Leaking Water an Emergency?
That depends. If it’s just external condensation, the answer is no. That’s a normal part of the AC function. However, if the leak is severe, causing property damage, or affecting electrical components, you’ll need an emergency repair by a professional.
Does Air Con Dripping Indicate a Bigger Problem?
Not always. Dripping due to external condensation is normal, especially from an outdoor unit. Where it could become an issue is if the leaking is inside your home, and due to a drainage or airflow problem.
Should I Turn off my Air Con if it’s Leaking?
Yes. It’s sensible to switch off the system if you spot a leak, just until the problem is identified. This can prevent further water damage and minimise the risk to electrical components.
