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 typically collected in a drain pan and transported through piping into your home’s drain system.

Unfortunately, a malfunction or sludge buildup could cause the piping to become backed up. When this happens, water backs up in the drain pan in your furnace or air handler. It can then spill into your home. This is decidedly troublesome if your furnace or air handler is kept in the attic or above a finished ceiling.

In most homes, building codes necessitate a secondary or safety drain pan that is installed underneath the furnace or air handler. This secondary drain pan possesses piping that is routed to the outside of the home. Typically, the outlet of the pipe is found above the outside of a window so it’s quickly noticeable if water begins 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 likely evidence the primary drain is clogged and water is now draining from the safety drain pan.

Here are the most common causes for why your AC is leaking water and how to take care of the issue. Some homes will also possess a safety device that can automatically turn off your AC if the drain becomes clogged. In this case your system will stop cooling until the drain is cleared of any obstructions. Regardless, if you discover water leaking, be sure to set your thermostat to “off” to stop any additional water damage and contact a Service Experts Heating, Air Conditioning & Plumbing service provider to correct the issues.

Leaking air conditioners often need professional help, 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 reaches the evaporator coil, water appears on the chilled metal surface. In the end, the water drains into a pan beneath the indoor coil within the furnace or air handler. As the cooling sequence continues, 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 flowing away properly. Leave the unclogging process to an Expert like Service Experts Heating, Air Conditioning & Plumbing to guarantee it’s done properly and without causing additional damage. Service Experts can also add a safety device that will quickly turn off your AC if the drain becomes blocked again later on, thus preventing water damage in your home. Of course, scheduling maintenance on your AC will help keep your condensate drain clear and unhindered.

2. Drain Line Is Disconnected

While not very common, the drain line connection to the drain pan can become loose or disconnected. This may be the cause if someone is working close to the unit or when swapping out the air filter. AC leaks can occur when the drain line is lose from the pan. Check your AC to find out if the drain line is still connected to the coil drain pan. If it is no longer connected, we encourage calling an HVAC technician to take care of this issue right away. Make an appointment with Service Experts Heating, Air Conditioning & Plumbing today.

3. Condensate Pump Isn’t Working

Some air conditioners use a condensate pump to properly drain the water. These pumps are needed when the home’s drain system is put above the AC unit. Even if the drain is clear, water might collect in the pan and leak out if the condensate pump is inoperable. First, double-check that the pump is being powered. If that’s not the case, the AC leak could be due to a broken condensate pump. You should contact an air conditioning contractor like Service Experts Heating, Air Conditioning & Plumbing to resolve the issue.

4. Evaporator Coil Is Grimy or Damaged

If you see tiny drips in lieu of a more substantial puddle around the outside of your furnace or air handler, water might be splashing off the evaporator coil rather than properly flowing into the drain pan and condensate line. This can take place if the coils are grimy, or if holes in the insulation smartest 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 like it’s supposed to, the refrigerant level may be lacking due to a leak. Air conditioners need refrigerant to produce cold air, so getting it inspected regularly during seasonal maintenance is extremely useful for the life span of your unit. Without a full supply of refrigerant, the evaporator coils could freeze over and cause the drain pan to overflow as they thaw. Contrary to some expectations, your AC does not need to be replenished unless there is a leak. The system is sealed and recharging is only required when a leak happens within the system. Call Service Experts Heating, Air Conditioning & Plumbing right away to repair AC refrigerant issues quickly.

6. Dirty Air Filter

Your air conditioner’s filter needs to be changed regularly to ensure enough airflow. Without adequate ventilation, the evaporator coils can become too cold and freeze. The evaporator coils will then thaw, causing excess water to collect in the drain pan—possibly producing an overflow. To resolve this, try changing your air filter. If the problem doesn’t go away, additional repairs might be needed. Luckily, HVAC technicians from Service Experts Heating, Air Conditioning & Plumbing are happy to serve you, ensuring the problem gets resolved.

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 below can cause the evaporator coils to freeze. Once thawed, the water and ice will drop off the evaporator coils and potentially create an overflow thanks 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 made to last, but nothing survives forever. If you possess an AC that is 12 years or older, the drip pan may be damaged or corroded after years of normal use. If the drain pan has holes in it, a water leak can 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 normally.

Our Experts Can Tackle All Your Air Conditioning Repair Needs

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

Our technicians are well trained, knowledgeable and certified to provide exceptional 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 advise signing up for a worry-free membership plan. This will sometimes help you catch AC issues, like water leaks, sooner so you can avoid future breakdowns while keeping your house cooler.

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

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