AC Leaking Water?
Here's Why — And What to Do Tonight

Water and air conditioning are supposed to go together — a working system in South Florida pulls gallons of moisture out of your air every day. The question is never whether your AC makes water. It's whether that water is going where it's supposed to.

When it shows up on your ceiling instead, it's one of four things. Here's how to tell which one you've got.

1. A clogged condensate drain line

This is the most common cause we find, by a wide margin. Your evaporator coil produces condensate, it collects in a drain pan, and it exits through a drain line. When that line clogs, the pan fills and overflows — usually into the ceiling below, or straight out of the air handler closet.

Florida clogs faster than almost anywhere else. Constant moisture inside a warm line grows biofilm — a slimy biological buildup that narrows the pipe, then blocks it. Add the dust that gets pulled through the system and you have a line that closes off gradually until one day it doesn't drain at all.

How you'll know: water in or around the air handler, or a ceiling stain directly below it. Often the system shuts itself off entirely — that's the float switch doing its job.

2. A tripped float switch (your system shut itself off)

If your AC stopped cooling and there's water around the unit, the float switch likely saved you. It's a small safety device that senses a rising drain pan and cuts power before the overflow reaches your ceiling.

People often mistake this for a dead air conditioner and start pricing replacements. It isn't. It's a clog with a working safety switch, and clearing the line usually brings the system straight back. Resetting the switch without clearing the clog just guarantees it trips again — often that same night.

3. Condensation on the ducts or registers

If the water is at a vent rather than at the unit, this is usually it. A cold metal register or an under-insulated duct sitting in a humid attic will sweat exactly like a glass of ice water on a July afternoon — and in South Florida the attic dew point stays high enough to make that happen for months at a time.

The root causes are duct insulation below R-8, leaks pulling humid attic air into the system, or a static pressure problem. We covered this in depth in our guide to why air vents sweat in South Florida homes, and it's what our duct sealing & repair service is built to correct.

4. A frozen coil that's now thawing

If you saw ice on the refrigerant lines or the indoor coil earlier and now you're mopping up water, the ice is melting faster than the drain pan can handle. The water is a symptom; the freeze is the actual problem.

Coils freeze from restricted airflow — a filthy filter, a dirty coil, collapsed ductwork — or from low refrigerant, which means a leak. Either way the system needs to be shut off and fully thawed before anyone can properly diagnose it. Anyone who promises an instant fix on a frozen system is guessing.

What you can safely do yourself

• Shut the system down at the thermostat and contain the water.
• Check your air filter. If it's grey and matted, replace it. A choked filter causes both freezing and overflow issues, and it's the one thing a homeowner can always fix.
• Look at the emergency drain pan under the air handler if you have attic equipment. Standing water there means the primary drain has already failed.
• Don't pour bleach down the drain line. It's common advice online, and it corrodes pan metal and fittings over time. Proper clearing is mechanical, not chemical.
• Don't just reset the float switch and walk away. You're overriding the safety that's protecting your ceiling.

When to call someone tonight

Call the same evening if water is actively spreading across a ceiling, if the system trips off again right after you reset it, or if there's standing water in the emergency pan. Those are all cases where waiting until morning costs more than the repair.

It can wait until morning if you've shut the system off, the water is contained, and nothing is dripping onto drywall.

We're open 7am to 11pm, seven days a week, with no after-hours surcharge — so an 8pm call is regular service. See our emergency AC repair page for how same-night service works.

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