How To Fix an AC Leak in Your House [A Step-by-Step Guide] 

Whether it’s an outpour of water or just a few drops — a leaking AC in the dead of summer is enough to make any homeowner panic. 

ServiceMaster of Lake Shore repairs Chicago homes damaged by AC leaks each year. We are no strangers to the causes or solutions. 

With that said, keep reading for a step-by-step guide on how to fix a leaking AC. 

6 Possible Signs of an AC Leak 

An AC leak isn’t always evident. Below are some tell-tale signs you should never ignore. 

1. AC Leaking Water Indoors 

It’s perfectly normal for your AC to leak water outside, but it shouldn’t leak water inside. If you notice this, something’s wrong. 

2. Compromised Cooling

The refrigerant running through your AC absorbs heat from your home that’s re-released as cool air. If your AC is blowing warm air or has weak airflow, a refrigerant leak may be the cause. 

3. Longer Runtime 

Air conditioners run longer in the summer than any other season.

However, if your unit continually exceeds the amount of time it typically takes to reach a set temperature, you may have an AC leak. 

4. Higher Electric Bill 

An unexpected increase in your electric bill means your AC is working less efficiently and requires attention. 

5. Hissing or Bubbling Noise

Strange hissing and bubbling is the sound of refrigerant leaking out of the evaporator coil. Water leaking inside your home can confirm this. 

6. Increased Humidity

Humidity is a sign you may have an AC leak. With that said, let’s discuss what causes an AC leak. 

Why Is My AC Leaking?

Your AC could be dripping water inside your house for a few reasons. We’ve listed the culprits below. 

1. Clogged Condensate Drain Line 

Your air conditioner runs the warm air it captures over evaporator coils filled with cold refrigerant.

The cold coils condensate and drip into a pan and down into a condensation line that leads outside. 

The condensation line is small, dark, and moist.

If your AC is not regularly maintained, mold, mildew, and algae can accumulate and clog the pathway. A blocked line prevents water from draining outside, causing it to overfill the drain pan and spill out into your home. 

2. Damaged Condensation Drain Pan 

Above, we learned that the drain pan catches condensation from the coil.

However, as an AC unit ages, the pan cracks and rusts. Water slips through these cracks and collects near the indoor component or drips into your home.  

3. Freon Leak 

A freon or refrigerant leak is costly, harmful to the environment, and dangerous to your health if left unattended. 

Freon leaks occur as normal wear-and-tear erodes the metal, valves, and seals that frequently contact freon.

The more refrigerant your AC loses, the less hot air flows through your system. This lowers the temperature and causes the evaporate or coil to ice over. When the ice melts, the water leaks into your home.  

4. Dirty Air Filter 

A dirty air filter is the easiest fix for an AC leak. It’s also inexpensive to fix.

A clogged air filter prevents the evaporator coil from absorbing hot air, causing the coil to freeze over and melt in the same manner mentioned above. 

How Do I Fix an AC Leak in My House? 

No need to look up, “how to stop an ac leak” — we’ve got step-by-step instructions for you. 

1. Check the Drain Pan

The status of your drain pan can identify the cause of your AC leak, making it one of the first things you should check. 

• First, turn off your AC. 
• Remove the access panel to the inside component of your unit. 
• Find the drain pan located beneath the evaporator coil. 
• If there is water in it, vacuum it dry. 
• Thoroughly clean the pan with soap and water.
• Use rags to re-dry the pan and skip to step two.
• If there is no water in the drain pan, grab a cup of water to pour into the pan. 
• If water drips out from the bottom of the pan, it has cracks. Use a flashlight to locate and mark them.
• Head to the store for some water-resistant sealant. 
• Seal both sides of the cracks. 
• Allow the sealant to dry for a few hours. 
• Retest the pan by pouring water into it. If the pan still leaks, contact a professional as you may need a new one. 

2. Clean the Condensate Drain Line 

• Locate the copper or PVC drain line near your outdoor condenser. 
• Use a wire brush to clean the inside of the drain line. 
• Place a shop vac at the opening, and let it run for a few minutes. 
• Place a bucket beneath the line. 
• Look inside and locate the copper or PVC drain line attached to the pan. 
• Remove the plastic cap and use the wire brush to clean the opening. 
• Pour distilled vinegar down the line. 
• Check to see if the vinegar drained into the bucket. 
• If it did, you’re in the clear! If it did not, contact a professional to clear the blockage. 

3. Check Your Air Filter 

Even if your drain line was the problem, changing a dirty air filter can only help.

• First, locate and examine your filter. 
• If it’s dirty, remove it and note the filter size. 
• Head to your local hardware store and purchase a new one. 
• Return home and replace it. 

If your drain line and filter were clear, you have larger issues that we address next.  

4. Evaluate Your Evaporator Coil 

If you are looking up, “how to fix a refrigerant leak in ac,” then you already know your problem. Let us save you the trouble. 

• Closely examine your evaporator coils located above the drain pan. 
• If you find even a small amount of ice build-up, you have a refrigerant leak that requires a professional’s attention. 

It’s challenging, dangerous, and frankly, impossible to completely repair freon leaks alone. A professional will quickly and easily locate and repair the leak for you. 

Have Water Damage Due to an AC Leak in the Chicago Area? We’re Here To Help!

You’ve figured out how to fix an AC leak in the house — congratulations! Now you need help addressing the damage.

ServiceMaster of Lake Shore has over 26 years of experience restoring Chicagoland homes damaged by AC water leaks.

For peace of mind and a quick solution from the industry’s top performers, call 312-707-8597