Water dripping down your air conditioning unit is unsettling. The last thing you want to witness is a messy puddle indoors. However, the role of your AC is to remove moisture from the air apart from cooling and heating. Therefore, an AC leaking water can indicate a technical issue.

Why Is There Water In The AC?

Your HVAC can control humidity levels as well as temperature. The indoor AC unit consists of evaporator coils. As the warm air from your home is drawn into your HVAC unit, it is blown over the cold evaporator coils, where condensation makes it less humid. This results in moisture to drip into a drain pan, leading to a condensate drain pipe. This pipe flows out the water from the AC. Having said that, when excessive moisture builds up in your air conditioner, removing the extra water is challenging. Hence, this leads your AC to leak water inside your home.

When The Water Leaks, Can I Use AC?

Your air conditioning will keep working even when it is leaking water. However, you may notice a decrease in its ability to cool down. Since the reason behind the leak is unknown, it would be safe to turn your unit off when you spot water dripping from your air conditioner. The internal AC components are sometimes damaged, leading to a compressor failure.

Water leakage from an indoor AC unit also affects your walls, ceilings, furniture, and other household items. Furthermore, excessive moisture leads to mold growth.

Reasons Why Your AC is Leaking Water

From clogged drain lines to dirty air filters, there can be many reasons your AC cannot remove moisture through the pipe.

1. Clogged Condensate Drain Line

This is one of the most common reasons for an AC leaking water. The moisture your unit collects during the dehumidification process contains dirt and debris. Over time, if the condensate drain line is not cleaned, this causes blockage. Eventually, water will start collecting in your unit, spilling out of the water. Some modern air conditioners have a cutoff switch that shuts down the unit if it detects a clogged drain line, a great option to protect your house from water damage.

Solutions for a clogged drain pipe:

  • Shut down your unit and look out for draining water.
  • Empty the drain pipe and thoroughly clean it to prevent mold growth.
  • Check how clogged it is. Then, use a long wire brush and thoroughly scrub the line to remove any gunk.
  • A special vacuum may be required if it is severely clogged. To ensure it is clean, pour a small amount of water
  • Lastly, ensure it seamlessly flows out of the other end.

2. Rusted or Damaged Drain Pan

A drain pan is located underneath your AC’s evaporator coils or in the air handler to catch condensation as it drips. From here, the water flows into the drain line and outdoors. Hence, If the drain pan is rusted, the water will start to leak rather than travel into the drain line. When your air conditioning unit is old, it will start showing signs of aging, and a rusted drain will occur. Drain pan can rust and corrode over time, causing your AC to leak water.


  • A broken drain pan must be carefully and securely sealed.
  • Clean the drain pan well, using a flashlight and pouring water to identify the cracks.
  • Use a good quality water-resistant sealant to patch the cracks and test the repair by pouring the water again.

3. Disconnect Line

If your drain line is not attached correctly, it will disconnect and result in your AC leaking water. The drain line can detach due to improper installation. Water can pool on the floor or ceiling in a disconnected drain line.


  • Inform Crump A/C and heating support to reconnect the drain line and avoid this problem soon.

4. Debris Filled Filter

Dirty air filters cause evaporator coils to freeze, leading to AC leaking water. The role of filters is to ensure proper air circulation. They trap air pollutants and allow clean air to enter your house. However, these particles and dust build-up within the filters and clog them entirely over time. Filter blockage is harmful to your indoor air quality and harms your unit, too. Moreover, warm air does not pass through easily when air filters are clogged. As a result, the refrigerant won’t absorb the heat, causing the evaporator coils to freeze after some time. When it defrosts, you may notice a puddle of leaking water inside your house.


  • First of all, make sure to collect the dripping water properly. Do not let it damage your floor or walls.
  • After that, start cleaning your filters.
  • Let the filters dry completely before returning them to your unit.
  • It is advisable to clean the air filter more often during the peak season when your air conditioning system is used for extended periods.
  • Clean them every two weeks and replace them every 3-4 months.

Final Takeaway

Now that you know the causes that could lead to your AC unit leaking water. However, most of your air conditioner leaking water issues can be prevented with proper maintenance. While tuning your indoor and outdoor units, the Crump A/C and Heating technician examines technical issues.

For further details, visit Crump A/C and Heating and contact us at (281) 533-9200.

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