1. Clogged drain line (most common)
Your AC removes moisture, which drains through a pipe. If it’s blocked, water backs up and drips.
Fix:
- Turn off the unit
- Locate the drain line (usually a small PVC pipe)
- Use a wet/dry vacuum to suck out the clog
- Or flush it with warm water + a little vinegar
Prevention:
Pour vinegar down the drain line every few months to stop algae buildup.
2. Dirty air filter
A clogged filter restricts airflow, causing the evaporator coil to freeze and then drip when it melts.
Fix:
- Replace or clean the air filter (cheap and quick)
- Do this every 1–3 months
3. Low refrigerant (more serious)
Low refrigerant can also freeze the coil, leading to excess dripping.
Signs:
- Weak cooling
- Ice on the unit
Fix:
- This isn’t DIY—call a technician
4. Damaged or rusted drain pan
If the pan that catches water is cracked, water will leak out.
Fix:
- Inspect the pan
- Replace it if damaged (or temporarily seal small cracks)
5. Improper installation or tilt (window units)
If the unit isn’t angled slightly outward, water won’t drain properly.
Fix:
- Adjust so it tilts slightly toward the outside
6. High humidity (normal but excessive dripping)
In very humid weather, more condensation forms.
Fix:
- This is partly normal, but make sure the drain system is clear
- Consider using a dehumidifier