A wet spot on the hall ceiling in Hunter Oaks and a puddle under a Watertown double-wide: two Lake City water leaks with different first steps

Attic unit or crawlspace unit: the first question

Two calls, the same week in June, the same complaint: water from the air conditioner. The first was from a two-year-old house in Hunter Oaks, where a brown ring had appeared on the hallway ceiling below the attic hatch. The second was from a double-wide in Watertown, where the homeowner had lifted a skirting panel to chase a smell and found a standing puddle under the packaged unit’s drain. Same cause family, a condensate drain that had stopped doing its job, and completely different first hours, because of where the water had to go.

So the first question the dispatcher asks is where the unit lives. Attic over finished ceilings, garage or closet on a slab, or outdoors feeding a crawlspace. Each has its own list.

The attic case: the pan, the float switch and the ceiling

New construction in Hunter Oaks, Forest Cove and Arbor Greene, and most of the 1990s-2000s two-stories in Callaway and Cypress Landing, put the air handler in the attic over living space. The unit sits in a secondary drain pan, and the main drain line runs to the outside. When the main line clogs, which it does every summer in a town with this much humidity, the coil’s condensate overflows the unit’s own pan into the secondary pan. If that pan has a float switch, the system shuts down and you get a warm house and a dry ceiling. If it does not, or if the secondary pan has rusted through or was never pitched, the water finds the drywall.

First hour: turn the system off at the thermostat. Put a bucket under the stain and poke a small hole at its lowest point to let the trapped water drain in a stream rather than a collapse. Go up to the attic hatch with a flashlight and look at the pan: standing water confirms it is the air conditioner and not the roof. Do not run the system again until the drain is cleared.

The crawlspace case: the drain that ends in the dirt

Roughly a third of Columbia County’s homes are manufactured, cooled by a packaged unit outside the skirting with a short duct into the floor. The condensate drain on those units usually runs a few feet and ends under the house, in the sand. In a dry climate that would be fine. In a place with 54 inches of rain a year and a wet season from June to September, the ground under the house never dries, the drain outlet sits in mud, and the line clogs from the bottom up. Water then backs up in the unit, spills at the cabinet, and runs under the house, where it feeds the mold and the smell that started the whole investigation. It also soaks the belly-board insulation and the duct run, which is why these houses so often have cool-air loss and water problems at the same time.

First hour: turn the unit off. Find the drain outlet under the skirting and clear it; a wet-dry vacuum on the end of the line pulls the clog out more often than not. Look at where the line ends and whether it can be rerouted to daylight past the skirting. If the puddle has been there for weeks, the insulation above it needs a look too.

Ranked causes for both

1. A clogged main drain line. Slime, dust and in spring a surprising amount of pollen, building up in the trap and the long horizontal runs. The cause in most Lake City water calls.
2. A float switch that was never installed, so the clog became a ceiling instead of a shutdown.
3. A drain line pitched wrong or kinked, holding water that grows the next clog.
4. A frozen coil that thawed. The meltwater overwhelms the pan. See the frozen-coil page; the cause is upstream.
5. A cracked or rusted secondary pan under an attic unit past fifteen years.
6. Sweating duct or refrigerant line in a hot attic or a wet crawlspace, dripping onto the ceiling or the ground and imitating a drain problem.
7. A disconnected drain fitting, often after someone else’s repair.

Get the drain cleared and the switch installed

When the stain means call tonight

Call 866-266-5709 the same evening if the ceiling is sagging, if water is reaching an electrical fixture or the air handler’s own electrical compartment, if the system will not shut off at the thermostat, or if clearing the outdoor end of the drain produced nothing and the pan is still filling. There is no after-hours charge, so there is no reason to let a pan overflow until morning. The visit clears the line properly from both ends, flushes the trap, re-pitches or reroutes a drain that was built to clog, installs a float switch where there is none, checks the secondary pan and verifies the coil is draining cleanly. On a manufactured home we also walk the belly board, because the water we find under the house is often the smaller part of what it has done. Then we leave you a small bottle of vinegar and a monthly habit.