Why Is My Split System Leaking Water? 5 Common Reasons

The scorching Australian summer has made air conditioners a must-have for homes and businesses alike. For smaller homes, split systems are the most popular variety, able to provide cost-effective cooling. But a common problem can occur with split systems—they can sometimes leak water. So if you’re asking the question “why is my split system leaking water?” – in this article, we’ll explain why it might be happening, and how you can fix it.

Why is my split system leaking water?

These are the most common reasons why your split system is leaking water inside or out, ordered loosely by frequency.

1. Blocked condensate drain (or AC drain line)

When an air conditioner is cooling your home, it creates condensation as a by-product, which must be removed from the system via the condensate drain. This is essentially a drain line that runs outside, expelling the liquid condensation into the ground next to the outdoor unit.

As air circulates through the system, airborne particles can be trapped by moisture, which can eventually build up in the condensate drain and create a blockage. When this happens, the condensation can’t be properly expelled from the system, which can cause the indoor unit of your split system to leak water.

If this happens, a technician will need to clear your condensate line to get it working properly again.

2. Dirty filters

Dirty filters are another common culprit for leaking split systems, because many people don’t even realise they have to be regularly cleaned. When the filter is completely clogged up with muck, the system’s evaporator coil receives much less air, which causes it to freeze. When this happens, the ice may start to melt from the coils, causing a leak.

Cleaning your filters is easy, and should be done at least once every six months. Here’s a general guide on how to clean your split system air conditioner.

3. High humidity

As split systems suck in air from the room being cooled, they take the humidity along with it, which the system condenses and ejects outside. If you’re living in a super-humid region like Queensland, sometimes the system will struggle to handle the high levels of humidity, especially if it’s a low quality system (i.e. not Panasonic, Daikin, or Mitsubishi Electric). When this happens, you may notice that the system leaks a little. This is generally nothing to worry about unless it’s a lot of water.

4. Broken condensate pump

The condensate pump is a small pump that pushes water through the condensate drain. When this breaks, there’s nothing to force the water through, so it collects in the system and leaks. This is another job for a technician, who can check elements like the pump’s microswitch and float, as well as checking for clogged areas of the system.

Thankfully, this issue is a less common one.

5. Pests

Australia is home to all kinds of pests that can block the drainage points of your AC system. Wasps, geckos, mice, rats, and possums are just a few of these critters, which build their nests in small, protected areas, and affect the system’s ability to remove condensation. The result is a leaky split system.

This issue is best diagnosed by a technician, who can check out common entry points (like the drainage points) for the pests, and help to remove them.

What to do if water is dripping from your split AC indoor unit?

Your most reliable and consistent port of call when it comes to rectifying a leaking air conditioner is, of course, an expert. Air conditioners are complex systems and attempting to fix one without the right skills, experience or equipment will often make the problem worse. Air conditioners can be quite expensive and for this reason, it is important that you leave any complex repair work to a specialist technician, as this will ensure that your air conditioner receives the care and attention that it needs.

Furthermore, there are safety hazards that you ought to be aware of with a malfunctioning air conditioner – particularly one that is leaking. Split system air conditioners are connected to your home’s power supply and as you can imagine, water and electricity do not go well together. Attempting a complex repair job on an air conditioning unit that is leaking water poses a direct threat to your safety and this is another reason why you should leave it to an expert.

Get in touch with the experts at Mercury Services today for all your air conditioner related problems.

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