Water around the air handler in Davis Shores during king tide week: condensate, or the bay?

Ten minutes, before anything else

Switch the thermostat to Off; while it runs, it keeps making water. Look at the water: how much, how far it has spread, and whether it is clear. Taste a drop on a fingertip, or at least smell it. Look up: is the air handler cabinet wet on the outside, is water coming from the drain pan, or is it dripping from a duct? If the unit is in the attic, go to the room below it and check the ceiling. Then take a photo and call. Those ten minutes decide whether this is a drain clog, a frozen coil, a pan failure or a flood, and they decide what we bring.

Tide water or condensate: how to tell in a Davis Shores garage

Davis Shores was dredged out of marsh in the 1920s and sits a few feet above the Matanzas River. The street floods on king tides a dozen or more times a year, and Matthew in 2016 and Irma in 2017 put feet of water in the garages. So a wet garage floor during the fall tide cycle is not automatically an air conditioner problem.

Condensate is tasteless, comes from the drain pan or the cabinet, and makes a puddle centered on the unit that spreads downhill from there. Tide water is salty or brackish, comes in under the garage door, and sits in the low spots of the slab regardless of where the air handler is. Rain blown in during a storm is fresh but arrives from the door or a wall vent, not from the machine. If the salty water reached the base of a unit sitting on the slab, the electrical parts need inspection before anyone restarts it, and the longer conversation is about a platform.

Call about water at the unit

The four places the water comes from

1. A clogged primary drain. The most common source in the city, especially September. Algae in the line, a crushed section, or a trap that dried out and lost its seal. The pan fills and overflows, or the float switch catches it and the system stops.
2. A frozen coil thawing. Ice built up from a dirty filter or a low charge melts in a volume the pan was never meant to handle. The leak is a symptom; the freeze is the problem.
3. A cracked or rusted pan. Two decades of humidity rusts a steel pan through; a plastic pan cracks where it was drilled for the drain fitting. Water escapes the pan before it can reach the drain.
4. Sweating. Uninsulated suction lines, a cabinet with the insulation fallen off, or a supply duct touching a hot garage ceiling, all condensing moisture out of St. Augustine’s air onto cold metal. Looks like a leak; is weather.

The brown ring under the attic unit in Murabella

In the 2000s subdivisions the air handler sits in the attic over the garage or a bedroom, and the first anybody knows of a drain problem is a brown ring on the ceiling. Code calls for a secondary pan under an attic unit with its own drain or float switch. In practice we find pans with no switch, pans rusted through, pans tipped off level by a sagging platform, and attics where the pan was never installed. By the time the ring shows, drywall and insulation are soaked, and the repair involves a drywall contractor as well as us.

Stopping it from coming back

One float switch guarding the primary drain, another in the secondary pan. A spring drain flush and a treatment tablet every maintenance visit. Insulation restored on lines and cabinet. For Davis Shores, the bayfront and the downtown flood zone, a platform that puts the air handler above the water line the street has actually reached, not the one the builder assumed. For attic units, a pan you can see from the hatch and a drain that exits where somebody will notice it dripping. None of that costs much next to a ceiling, and all of it is routine on our maintenance visits.