Why Is My Window Air Conditioner Leaking Water Inside?
Indoor leakage usually means the unit is tilted toward the room, airflow is restricted, ice is melting, the drainage path is obstructed, rain is entering around the installation, or the base pan has been damaged.
What to know
- Disconnect power when water reaches the cord, plug, outlet, controls, or other electrical equipment.
- Check the exact model’s installation angle rather than applying one universal slope.
- Clean the filter and allow all ice to melt before restarting a frozen unit.
- Persistent leakage, pan corrosion, repeated freezing, or structural installation trouble requires service.
The direct answer
Water dripping into the room is not normal operation. A window air conditioner removes moisture from indoor air, and that condensate should remain in the designed base pan, be reused by the outdoor fan where applicable, or move toward the outdoor side.
Indoor leakage commonly comes from an inward slope, restricted airflow, an iced coil melting, a blocked drainage path, a damaged pan, rain entering around the window, or an installation that has shifted.
Address electrical risk first
Turn the unit off and disconnect it when water reaches the plug, outlet, cord, controls, or internal wiring; the outlet sparks or trips; or water runs down the wall toward another electrical device.
Do not unplug the unit with wet hands or while standing in water. When the receptacle is wet, shut off the circuit only from a dry, safely accessible breaker panel and obtain qualified help.
Some outdoor water is normal
Water dripping from the outdoor side can be normal, particularly during humid weather. Moisture condenses on the indoor coil and moves into the base pan. GE explains that outdoor dripping and water in the base pan are expected on many room air conditioners. [2]
Do not drill a drain hole or remove a plug merely because water is visible. Some designs intentionally retain water so the outdoor fan can splash it across the condenser coil. Follow the exact manual.
Check the installation angle
Many conventional window units sit level from side to side and slope slightly toward the outdoors. GE commonly specifies about a quarter-inch outward tilt for traditional models. [1]
That measurement is not universal. U-shaped, saddle-style, through-wall, and bracket-supported models can have different requirements.
Check whether the interior side has dropped, the window sash shifted, support foam compressed, a bracket loosened, or the cabinet twisted. A heavy air conditioner needs proper structural support. Do not lean out of an upper-story window or lift it alone.
Clean the filter
A dirty filter reduces airflow across the indoor coil. That can lower coil temperature, encourage ice, reduce cooling, increase runtime, and cause water to collect where it should not.
Turn the unit off and clean or replace the filter according to the manual. Do not operate it permanently without the filter.
Look for ice
Check the indoor coil and louvers for frost, solid ice, weak airflow, or water appearing after the unit is switched off.
When frozen:
- Turn cooling off.
- Allow the ice to melt completely.
- Protect the wall and floor from water.
- Clean the filter.
- Open blocked vents.
- Restart only after thawing.
Do not chip ice from the coil. Thin tubing and fins are easily damaged. Repeated freezing can indicate a blower, sensor, coil, or refrigeration problem requiring service.
Inspect only approved drainage points
Look for leaves, insects, algae, a kinked optional hose, a hose rising uphill, or a damaged base pan, but inspect only the areas the manufacturer identifies as user-accessible.
Do not insert wire, drill bits, screws, or chemical drain cleaner into the cabinet. Some models have no user-serviceable drain opening.
Consider rain entry
A leak that appears during rain but not during cooling suggests gaps around side panels, missing weather seals, wind-driven rain, a damaged window opening, or a leak unrelated to the air conditioner.
Do not seal condenser louvers or required ventilation openings.
Base-pan damage
Service is appropriate when water emerges from an unexpected seam, the cabinet is heavily corroded, the unit was dropped, a previous owner drilled holes, or the pan is visibly cracked.
Bottom line
Turn the unit off when water threatens electrical equipment. Then check the model-specific slope, clean the filter, allow ice to melt, and inspect approved drainage and sealing points. Persistent leakage, corrosion, pan damage, or repeated freezing requires repair rather than another towel beneath the machine.
Limits and cautions
- Some room air conditioners intentionally retain water in the base pan, so outdoor dripping and visible pan water can be normal.
- Slope and drain-plug instructions differ among conventional, U-shaped, saddle, and through-wall designs.
- Upper-story exterior inspection and structural support work require appropriate equipment and experience.
Source notes
- Room Air Conditioner - Water Dripping InsideGE Appliances
- Room Air Conditioner - Water Dripping OutsideGE Appliances
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