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AC Leaking Water Inside
in Sioux Falls, SD
Sioux Falls summers are humid enough that AC units pull a lot of moisture out of the air, and all that water has to go somewhere. It drips off the indoor coil into a drain pan, then flows out through a drain line. When that line clogs or the pan cracks, water ends up on your floor or ceiling instead. Water damage from a leaking AC unit can show up fast, especially in finished basements in neighborhoods like Tuthill Park or McKennan Park.
Quick Answer
Water leaking from an indoor AC unit in Sioux Falls is almost always a clogged drain line or a frozen coil that melted. The drain line collects condensation and when it clogs, water backs up and spills over. A technician can clear the line and check for the underlying cause. Call (605) 231-9370 before the water damages your ceiling, drywall, or flooring.
Telltale Signs
Warning Signs to Watch For
- Standing water on the floor around the furnace or air handler
- Water stains on the ceiling below a second-floor air handler
- The drain pan under the indoor unit is full of water
- Mold or musty smell near the air handler or in nearby rooms
- The system shuts off on its own due to a float switch tripping
Root Causes
What Causes AC Leaking Water Inside?
Clogged Condensate Drain Line
Algae, dust, and mold grow inside the plastic drain line over time and eventually block it completely. Water backs up into the drain pan and overflows onto whatever is below. In Sioux Falls, central AC units run hard from June through August, which means the drain line is carrying water constantly for three months straight.
The Fix
Condensate Drain Line Flush
A technician uses a wet vac or pressurized air to clear the blockage, then flushes the line with a mild cleaner. Installing a float switch that shuts the system off before overflow is a good add-on that prevents water damage.
Cracked or Rusted Drain Pan
The drain pan sits under the coil and catches condensation. Over years of use, metal pans rust through and plastic pans crack from age and temperature changes. Units installed in Sioux Falls before 2005 are likely to have original drain pans that have never been replaced.
The Fix
Drain Pan Replacement
A technician removes the old pan and installs a new one sized for the unit. A cracked pan cannot be patched reliably for the long term and will keep leaking even after repairs.
Frozen Coil Thawing Out
When the indoor coil freezes due to low refrigerant or poor airflow, the ice eventually melts and the drain pan cannot handle that much water at once. The overflow spills out onto the floor. This happens frequently in Sioux Falls during the first heat wave of summer when units have sat idle all winter and problems go unnoticed.
The Fix
Airflow and Refrigerant Inspection
A technician finds why the coil froze in the first place, fixes that root cause, and checks the drain system. Treating only the water without addressing the freeze means it will happen again.
Self-Diagnosis
Which Cause Applies to You?
Check the signs you're observing to narrow down the likely root cause before your inspection.
| What You're Seeing | Clogged Condensate Drain Line | Cracked or Rusted Drain Pan | Frozen Coil Thawing Out |
|---|---|---|---|
| Drain pan is full but the drain line outlet has no water flowing | |||
| Visible crack or rust hole in the bottom of the drain pan | |||
| Ice visible on the coil or line just before the water appeared | |||
| Musty smell started around the same time as the leak | |||
| Water appeared after a very hot day following weeks of normal operation | |||
| Pan is dry but water is on the floor directly below the pan |
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