How to fix water leaks in your central air conditioner

As summer approaches, a well-functioning central air conditioning system is essential for maintaining comfort at home. However, when your AC unit starts to leak, it can be a frustrating and potentially damaging issue that requires prompt attention. Leaks not only create a mess, but can also lead to water damage, mold growth, and decreased efficiency – problems that can be costly if left unchecked. Fortunately, many common causes of central AC leaks can be identified and resolved through basic troubleshooting and you can fix the issue yourself without the need for professional service.

If you find out that you need any replacement parts for your appliance while you’re troubleshooting, you can enter your model number at AppliancePartsPros.com to order them. Most orders arrive in just two business days, and we have thousands of free guides to show you how to install your new parts.

The troubleshooting information provided in this article may not apply to your specific appliance model. While we strive to offer helpful advice for DIY appliance repairs, variations in models and configurations can lead to differences in troubleshooting steps, error codes and part replacements. For the most accurate guidance, we strongly recommend consulting the technical sheet for your specific appliance model.

Safety precautions

When working on any appliance, remember to keep safety first. Here are some tips to keep in mind: 

• Always power off and unplug your appliance or switch off the circuit breaker before attempting any maintenance or replacement work. This keeps you safe by preventing any risk of injury from electric shock.
• Wear insulated work gloves to protect your hands from sharp metal parts, pinching hazards and debris.
• Take your time and don’t rush while working to prevent accidents and personal injuries.
• Work in a well-lit area so you can clearly see and access the interior parts.
• Clear your workspace of clutter and other obstacles. Keep children and pets away from the work area.
• Never work on internal parts with bare wet hands. Make sure the work area is completely dry.
• Check your user manual to see if there are specific installation or safety instructions for your part or appliance. 
• Be gentle when handling or removing parts. Excessive force might damage the appliance or cause injury.
• Wear safety glasses when working with chemicals, dust or cleaning large debris to prevent injury. 
• If the appliance has recently been used, give it plenty of time for any heating parts to cool down before working on it. 
• Take pictures or make a note of wiring terminals or other connections before disconnecting to prevent any problems with reassembly.
• When working with wires, avoid touching any exposed wires or terminals. If you need to touch a wire, use a non-conductive tool or wear insulating gloves to prevent electrical shock.

Tools and materials needed

• Wet/dry shop vacuum
• Drain snake or plumber’s snake
• Screwdriver set

The specific tools required may vary depending on the model of your appliance and the type of fasteners used on it. Always consult the user manual or refer to any specific instructions provided by the manufacturer for the recommended tools for your appliance model.

Troubleshooting steps

High humidity levels:

1. Check the humidity levels in the home, especially during periods of high outdoor humidity.
2. Consider installing a dehumidifier or ensuring proper ventilation to reduce the overall humidity levels.
3. Ensure the air conditioner is operating efficiently and able to adequately remove moisture from the air.

Clogged condensate drain line:

1. Locate the condensate drain line, which is typically a PVC or plastic pipe that runs from the indoor unit to the outside or a floor drain.
2. Use a wet/dry vacuum or a drain snake to clear any blockages in the line.
3. Check for kinks or bends in the drain line that may be restricting water flow.
4. Ensure the drain line is sloped properly to allow for gravity-assisted drainage.
5. Consider installing a condensate pump if the drain line does not have enough slope.

Damaged drain pan:

1. Inspect the drain pan, usually located underneath the indoor unit, for cracks, rust, or misalignment.
2. If the drain pan is damaged, it may need to be replaced.
3. Check the drain pan’s connection to the drain line to ensure it is properly aligned and sealed.
4. Ensure the drain pan is level and positioned correctly to catch any condensation.

Blocked air filter:

1. Locate the air filter, typically found in the return air duct or the indoor unit, and inspect it for dirt, dust, or debris buildup.
2. Clean or replace the air filter according to the manufacturer’s recommendations.
3. Ensure the filter is the correct size and installed properly.
4. Check for any obstructions that may be restricting airflow through the filter.

Worn or damaged seals:

1. Inspect the seals around the unit’s panels, doors, and connections for cracks, tears, or deterioration.
2. Replace any damaged seals to prevent water leaks.
3. Ensure the seals are properly installed and provide a tight seal.

Oversized unit:

1. Consult the manufacturer’s specifications or have a professional HVAC technician evaluate the system’s sizing to ensure it is appropriate for the space being cooled.
2. If the unit is oversized, it may short-cycle, leading to excessive condensation and leaks.
3. In this case, the unit may need to be replaced with a properly sized system.

Refrigerant leaks:

1. Have a licensed HVAC technician perform a leak test to identify any refrigerant leaks in the system.
2. They can use a leak detection dye or an electronic leak detector to pinpoint the source of the leak.
3. Depending on the severity of the leak, the technician may need to recharge the refrigerant or repair the leaking component, such as a coil or line set.

Additional information

Thank you for reading! We hope this guide helped you get your central air conditioner working again.

If you have any other appliance repair needs or projects, don’t hesitate to explore our other troubleshooting guides and videos. 

If you need replacement parts or some extra help with ordering them, grab your model number and head over to AppliancePartsPros.com, where you can chat with a pro, read our DIY blog and more.

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