Why Is My AC Leaking Water Inside My Home?

If you've spotted water dripping from your indoor AC unit or puddles forming around it, your first instinct is right — something is wrong, and it needs attention. The good news is that a leaking AC is one of the more common issues we see in Sarasota and Bradenton homes, and in most cases it has a straightforward fix.

First things first: turn your thermostat to "Off" right now. Running the system while it's leaking can cause water damage to your ceiling, walls, and flooring — and make the repair more expensive.

Think you need an AC tech? Schedule a service call online or call us at 941-366-7676. We're available 24/7.

Why Does Water Form on Your AC in the First Place?

Your AC system doesn't just cool air — it also pulls humidity out of it, which is a big deal here in Sarasota. Here's how it works:

Your indoor unit contains an evaporator coil that gets very cold as refrigerant flows through it. When warm, humid air from your home blows across that coil, moisture in the air condenses on the coil's surface — the same way a cold glass sweats on a hot day.

That condensation drips off the coil into a drain pan, then flows out of your home through a condensate drain line — usually a white PVC pipe that exits through a wall or into a floor drain.

When any part of that system gets blocked, broken, or overwhelmed, water ends up somewhere it shouldn't — inside your home. Here are the most common reasons why.

Cause 1: Clogged Condensate Drain Line

This is the most frequent cause of AC water leaks in Florida homes — and Florida's heat and humidity make it even more likely here than in other parts of the country.

Over time, algae, mold, dirt, and sludge build up inside the condensate drain line. When the line gets clogged, water has nowhere to go and backs up into the drain pan — and eventually overflows into your home.

If the clog is minor, you may be able to clear it by pouring a cup of distilled white vinegar into the drain line access point (usually a T-shaped PVC fitting near your indoor unit). For stubborn blockages, a technician has a specialized vacuum tool that pulls the clog out cleanly.

Prevention tip: Pour vinegar down the drain line every 1–3 months to keep algae from building up. This is especially important during Florida's summer months when your AC is running constantly.

Cause 2: Dirty Air Filter

A clogged air filter is one of the easiest problems to fix — and one of the most commonly overlooked. When the filter is too dirty, it restricts airflow across the evaporator coil. Without enough warm air moving over it, the coil gets too cold and freezes over.

When the ice eventually melts, it produces far more water than the drain pan can handle — and it overflows.

Check your filter right now. If it's grey and clogged with dust, replace it. In Sarasota and Bradenton homes, filters should generally be changed every 1–3 months depending on how often your AC runs and whether you have pets.

Cause 3: Low Refrigerant

Low refrigerant causes the pressure inside your AC system to drop, which makes the evaporator coil get far colder than it should. The result is the same as a dirty filter — the coil freezes, the ice melts, and water overflows the drain pan.

Signs you may be low on refrigerant:

•      Your home isn't cooling as well as it used to, even with the thermostat turned down

•      You hear a hissing or bubbling sound coming from the indoor or outdoor unit

•      You notice ice forming on the refrigerant lines or the outdoor unit

Low refrigerant almost always means there's a leak somewhere in the system — refrigerant doesn't simply run out on its own. A licensed technician will locate the leak, repair it, and recharge the system. In older units where the leak is severe or the refrigerant type is being phased out, replacement may be the more cost-effective path.

Cause 4: Cracked or Overflowing Drain Pan

The drain pan sits directly beneath the evaporator coil and catches all the condensation that drips off it. In older AC systems — typically those 10 years or older — the drain pan can crack, rust through, or simply deteriorate to the point where it no longer holds water properly.

If your system is newer but the pan is overflowing, the issue is likely a clogged drain line (see Cause 1) rather than the pan itself. But if the pan is visibly rusted, cracked, or damaged, it will need to be replaced.

Cause 5: Disconnected or Improperly Installed Drain Line

Sometimes the condensate drain line simply comes loose from the fitting it's connected to — especially in systems that have been serviced recently or in homes where the air handler is in a tight space. When the line disconnects, water drains directly into your home instead of outside.

This one is usually a quick fix — but it requires someone to physically inspect the drain line and reconnect or reseal it properly.

Still Leaking? Let Aqua Take a Look.

If you've checked your filter and it's clean, but your AC is still leaking — or if you're not comfortable diagnosing it yourself — it's time to call a professional. Water damage builds up fast, especially in Florida's humidity.

Aqua Plumbing & Air has been taking care of Sarasota, Bradenton, and Lakewood Ranch homes since 1974. Our HVAC technicians are available 24/7 and can diagnose and fix the problem the same day in most cases.

We'll also ask whether your system has a float switch installed — a small but important device that automatically shuts your AC off if the drain pan starts to overflow. If yours doesn't have one, we'll recommend adding it to prevent future leaks from causing damage.

Schedule a service call online or call us at 941-366-7676. We're here when you need us.