Is Your Air Conditioning Leaking Water? Here Are 8 Possible Causes

An air conditioner (AC) keeps your house cool and comfortable by pulling heat and humidity from the air. As the AC extracts humidity from the air, it generates condensate, or water, in your furnace or air handler. This water is usually collected in a drain pan and sent through piping into your home’s drain system.

As a side effect, damaged pipes or sludge buildup may cause the piping to become backed up. When this happens, water backs up in the drain pan inside your furnace or air handler. It can then leak into your home. This is namely troublesome if your furnace or air handler is located in the attic or above a finished ceiling.

In a majority of homes, local codes require a secondary or safety drain pan that is installed underneath the furnace or air handler. This secondary drain pan uses piping that is directed to the outside of the home. Typically, the outlet of the pipe is placed above the outside of a window so it’s quickly noticeable if water is draining from this pipe outlet. It is not normal for this to occur. If you see water draining from piping on the outside of your home, this is often evidence the primary drain is backed up and water is now draining from the safety drain pan.

Here are the most general causes for why your AC is leaking water and how to resolve the issue. Some homes will also have a safety device that should automatically switch off your AC in the event the drain becomes clogged. In this case your system will stop cooling except if the drain is cleaned of any obstructions. Regardless, if you spot water leaking, be sure to set your thermostat to “off” to avoid any further water damage and contact a Service Experts Heating, Air Conditioning & Plumbing service provider to correct the issues.

Leaking air conditioners frequently demand professional repairs, which is why we’re here to assist you at Service Experts Heating, Air Conditioning & Plumbing. We happily deliver Expert air conditioning repair across North America, backed by a 100% Satisfaction Guarantee.*

1. Condensate Drain Is Blocked

When hot, humid air runs along the evaporator coil, water condenses on the cold metal surface. In the end, the water drains into a pan underneath the indoor coil inside the furnace or air handler. As the cooling sequence occurs, the condensate flows out of the pan and into drain piping before the pan becomes full.

However, mold, mineral deposits, dirt and other debris could clog the drain. This keeps the water from draining away correctly. Leave the unclogging process to an Expert like Service Experts Heating, Air Conditioning & Plumbing to ensure it’s handled properly and without causing additional damage. Service Experts can also add a safety device that will quickly turn off your AC in the event the drain becomes clogged again sometime after, thus preventing water damage within your home. Of course, scheduling maintenance on your AC will help keep your condensate drain clean and open.

2. Drain Line Is Disconnected

While not very common, the drain line connection to the drain pan may become loose or disconnected. This will sometimes be the cause if someone is working around the unit or when changing out the air filter. AC leaks may occur when the drain line is disconnected from the pan. Take a look inside your AC to see if the drain line is still connected to the coil drain pan. If it is no longer connected, we recommend calling an HVAC technician to take care of this issue immediately. Make an appointment with Service Experts Heating, Air Conditioning & Plumbing today.

3. Condensate Pump Isn’t Working

Some air conditioners require a condensate pump to properly drain the water. These pumps are compulsory when the home’s drain system is located above the AC unit. Even if the drain is free of obstructions, water might back up in the pan and leak out if the condensate pump is broken. First, determine that the pump is currently powered. If that’s not the case, the AC leak may be due to a broken condensate pump. You should call an air conditioning contractor like Service Experts Heating, Air Conditioning & Plumbing to resolve the issue.

4. Evaporator Coil Is Grubby or Damaged

If you see little drips instead of a larger puddle near the outside of your furnace or air handler, water may be splashing off the evaporator coil compared to properly moving into the drain pan and condensate line. This can happen if the coils are grimy, or if holes in the insulation easiest approach to keep the evaporator coil from going downhill is to keep up with annual air conditioning maintenance using a Service Experts Heating, Air Conditioning & Plumbing membership.

5. Low Refrigerant Level

If you discover a leak and the AC isn’t cooling properly, the refrigerant level may be lacking because of a leak. Air conditioners rely on refrigerant to produce cold air, so getting it checked regularly during seasonal maintenance is highly useful for the longevity of your unit. Without adequate refrigerant, the evaporator coils might freeze over and cause the drain pan to overflow as they thaw. Despite some expectations, your AC does not need to be refilled unless there is a leak. The system is sealed and recharging is only done when a leak happens inside the system. Call Service Experts Heating, Air Conditioning & Plumbing as soon as possible to resolve AC refrigerant issues quickly.

6. Dirty Air Filter

Your air conditioner’s filter has to be changed regularly to encourage enough airflow. Without adequate ventilation, the evaporator coils could become too cold and freeze. The evaporator coils will then thaw, causing excess water to accumulate in the drain pan—potentially producing an overflow. To resolve this, try changing your air filter. If the problem persists, further repairs may be needed. Fortunately, HVAC technicians from Service Experts Heating, Air Conditioning & Plumbing are willing and able to serve you, ensuring the problem gets solved.

7. Outdoor Temperature Is Too Cold to Run AC

Air conditioners are built to run during warm weather. Starting your AC when outdoor temperatures are 60 degrees Fahrenheit or lower may cause the evaporator coils to freeze. Once thawed, the water and ice will drop off the evaporator coils and potentially create an overflow due to ice blocking the drain pan opening. If a water leak persists, schedule a Service Experts Heating, Air Conditioning & Plumbing technician backed by our 100% service guarantee* to help solve the problem.

8. Damaged Drip Pan

Air conditioners are manufactured to last, but nothing survives forever. If you use an AC that is 12 years or older, the drip pan might be damaged or corroded after years of normal use. If the drain pan has holes in it, a water leak may appear as condensate seeps directly through it. Service Experts Heating, Air Conditioning & Plumbing can replace the drain pan and ensure your AC gets back to working properly.

Our Experts Can Handle All Your Air Conditioning Repair Needs

Whatever the reason why your AC is leaking water, Service Experts Heating, Air Conditioning & Plumbing can repair the damage. We’ll troubleshoot and fix your air conditioner, getting it back to running again right away.

Our technicians are thoroughly trained, knowledgeable and certified to provide dependable work. We have full confidence in our repairs—in fact, we back up everything we perform with a one-year 100% Satisfaction Guarantee!*

We’ll even suggest a worry-free membership plan. This could help you catch AC issues, like water leaks, sooner so you can avoid future breakdowns while keeping your house comfortable.

Contact us at to schedule your air conditioning appointment in North America today!