Leaking air conditioning units is a major inconvenience, especially during hot weather. It’s frustrating to see water dripping from a device meant to keep you cool and comfortable.
But before you throw in the towel, it’s best to know that there are a number of common culprits behind these leaks — many of which have relatively simple fixes.
So, in this blog, we’ll share the most frequent causes of AC water leaks and provide practical solutions to help you get your AC unit back in working order.
Let’s get into it, shall we?
Why is My AC Leaking Water? Causes and Fixes
Don’t panic if you notice water leaking from your AC unit. Here are some common causes and easy fixes.
- Clearing a Clogged Condensate Drain Line
A clogged condensate drain line is a prime suspect when your AC unit starts leaking. Your AC naturally produces condensation as it cools warm air, and this moisture needs somewhere to go. The condensate drain line, usually a white PVC pipe, is designed to carry this water away from the indoor unit.
Over time, the line can become clogged with debris like dust, dirt, algae, or mold, preventing the water from draining properly and resulting in leaks.
To tackle a clogged drain line, start by locating the pipe. It typically exits your indoor AC unit and runs either to the outside near your condenser unit or into a dedicated floor drain inside your home. If you’re having trouble finding it, a trusted air conditioning service near me can help.
Once you’ve found it, use a wet/dry vacuum to clear the blockage. Attach the vacuum hose to the end of the drain line — making sure to create a tight seal. Turn the vacuum on and let it run for a few minutes to try to suck out any debris obstructing the flow.
- Replacing a Dirty Air Filter
Your AC’s air filter plays a crucial role in keeping the system running smoothly and preventing issues, including water leaks. A dirty air filter restricts airflow over the evaporator coils, which are essential for the cooling process.
When these coils don’t get enough air movement, they become extremely cold and can freeze. As the ice melts, the excess water can overwhelm your AC’s drain pan — leading to leaks.
The solution here is simple — replace your dirty air filter with a clean one. Manufacturers typically recommend replacing air filters at least every month during peak use or as specified in your AC unit’s instruction manual.
If you have pets or live in a particularly dusty environment, you may need to change your filters more frequently. If you have a reusable filter, follow the manufacturer’s instructions for cleaning it thoroughly.
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Thawing Frozen Evaporator Coils
If you suspect your AC’s evaporator coils have frozen over (often indicated by a visible layer of ice), there are a few steps you need to take. The most important thing is to turn off your AC system immediately at the thermostat.
Allowing the unit to continue running with frozen coils can cause damage. Once it’s powered down, leave the unit alone to let the ice melt naturally. This may take several hours.
After the ice has completely thawed, it’s time to address the underlying cause of the freezing. The most common culprits are a dirty air filter, low refrigerant levels, or a faulty blower fan.
Replace the air filter if it’s dirty — remember this is crucial for good air conditioning maintenance. If you suspect a refrigerant leak or a blower fan issue, it’s time to call in a qualified HVAC technician.
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Repairing or Replacing a Damaged Drain Pan
The condensate drain pan sits directly below your evaporator coils and is responsible for collecting the condensation that forms on them. Over time, especially in older AC units, this pan can become rusty, cracked, or develop holes.
When this happens, the water won’t drain properly and will instead leak out of the pan.
First, carefully inspect the drain pan for any visible signs of damage. If you find small holes or cracks, you might be able to patch them temporarily using a waterproof epoxy.
Keep in mind that this is usually a short-term solution, and it’s best to replace the entire drain pan if it’s severely damaged or very old. Replacing the drain pan often requires some disassembly of your AC unit, so this might be a task better suited for an HVAC technician.
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Addressing Low Refrigerant
If your AC system is leaking due to low refrigerant levels, it’s best to call a licensed air conditioning contractor. Refrigerant is a specialized substance that should only be handled by certified professionals. They have the knowledge and tools to safely locate and repair the leak, and then recharge the system with the correct amount of refrigerant.
Attempting to fix a refrigerant leak yourself can be dangerous and may cause further damage to your AC unit.
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Correcting Improper Installation
Sometimes, water leaks stem from the initial installation of your AC unit. If the indoor unit is not perfectly level, it can cause condensation to pool in certain areas rather than draining properly.
This can overload the drain pan and lead to leaks. Check that your unit appears level using a basic spirit level. If you notice it’s tilted significantly, you’ll need to contact an HVAC technician to assess and potentially reinstall the unit for proper drainage.
- Troubleshooting a Broken Condensate Pump
Some AC systems, especially those installed in basements or other locations where gravity drainage is difficult, incorporate a condensate pump. This pump is responsible for lifting the collected water up and out of the system, says David Martinez, VP Enterprise & OEM Accounts at Cybernet Manufacturing.
If the condensate pump malfunctions, water can back up and cause leaks.
First, check if the pump has power. Next, inspect the pump and clean out any debris that may be obstructing it. If the pump appears damaged, a replacement may be necessary.
Conclusion
Don’t stress if your AC starts dripping. Often, the problem has a surprisingly easy fix — think clogged pipes or a dirty filter.
Understanding what might be going wrong can save you a lot of worry (and maybe a service call). Remember, giving your AC some regular TLC with filter changes and checkups helps catch small problems before they cause leaks.
But, if you think it’s something serious, like low refrigerant or a weird issue with the pump, it’s best to call the expert. They’ll have your AC back to its cool, drip-free self in no time.
