Why is My AC Leaking Water?

Discovering a puddle of water around your indoor or outdoor air conditioning unit can be concerning. While it's a common issue, it's not one you should ignore, as it can lead to water damage and more significant HVAC problems. Here are the most frequent culprits behind a leaking AC.

1. Clogged Condensate Drain Line

This is by far the most common cause. As your AC cools your home, it removes humidity from the air. This moisture, called condensate, collects in a drain pan and flows out of your home through a condensate drain line. Over time, this line can become clogged with dirt, sludge, and algae. When the line is blocked, the water has nowhere to go but back into the drain pan, which eventually overflows.

2. Damaged or Rusted Drain Pan

If your air handler is older (typically over 10-12 years), the drain pan itself can rust, crack, or become damaged. This allows the condensate to leak out before it ever reaches the drain line, causing water damage to the area around your indoor unit.

3. Disconnected Drain Line

It's possible for the connection between the drain pan and the drain line to become loose or disconnected. If this happens, the condensate will spill out directly from the unit instead of being properly drained away.

4. Frozen Evaporator Coils

When your system's evaporator coils get too cold, the condensation on them can freeze. This is often caused by restricted airflow from a dirty filter or low refrigerant levels. When the ice eventually melts, the drain pan can be overwhelmed by the large amount of water, causing it to overflow.

5. Condensate Pump Failure

If your indoor unit is located in a basement or attic, it may use a condensate pump to push the water outside. If this pump malfunctions or breaks, it can't remove the water, leading to an overflow and a leak.

What Should You Do?

If you notice water leaking from your AC unit, turn it off immediately to prevent further water damage. You can check for a simple clog in the drain line at the exit point outside your home, but for most of these issues, a professional diagnosis is necessary.

Ignoring a leak can lead to costly water damage, mold growth, and serious damage to your HVAC system. Call the experts at Home Run Heating and Air to quickly diagnose and fix the problem, ensuring your system runs safely and efficiently.