Why the drain line backs up
The usual culprits are a clogged drain line, a condensate pump that’s quit, or a long stretch of hot, humid days. During those stretches, the AC runs nonstop and makes more water. If the drain is plugged while the AC is running hard, the pan can fill in an afternoon.
Many systems have a second pan under the unit, and some have a float switch that shuts the AC off when the pan fills. If that second pan is overflowing too, the drain line has been backed up for a while.
Turn the AC off and check the pan
Switch the system off at the thermostat so the coil stops making water, then check the pan under the unit. If the pan is full or overflowing, the drain line is the problem. Towel up the water on the floor, take photos, and call an HVAC tech to clear the line. If an attic unit is leaking through the ceiling, move things out from under the wet spot.
Where condensate water ends up
When a closet AC unit leaks, it can soak the carpet and pad in front of it and the bottom of the closet walls. An attic unit can wet insulation and ceiling drywall. We extract the water, pull wet pad and baseboards, open the bottom of walls where moisture readings show they’re wet, and dry the affected areas.
Restorers count AC condensate as Category 2, or gray water, under the Category 1, 2, and 3 water system. Because of that category, we remove the carpet pad it soaked.
Insurance and cost
The Texas Department of Insurance says most policies cover a sudden and accidental release of water and most don’t cover a continuous leak, so a pan that overflowed once and a drip that ran all summer aren’t the same claim. Angi’s Austin page, updated August 2026, publishes a range of $3,870 to $8,333 for water damage restoration in Austin, averaging $6,101. Our guides cover Texas homeowners insurance and what water damage costs.