Have you recently spotted a puddle of water forming around your indoor air conditioning unit? Or have you noticed water stains on the ceiling below your attic unit or streaks dripping down the wall near your system? The sight of this water is certainly alarming and often begs the questions, “Is this normal?” and “Is this going to cause water damage?”
While your A/C unit does produce a bit of water during its normal cooling process, that water should never pool, puddle, or drip into your home. So, if you’re seeing water where it shouldn’t be, note that the unit’s drainage process has been interrupted, and you will want to troubleshoot the problem right away to avoid water damage, mold growth, and further system damage.
To help you get started, we’ve prepared a detailed breakdown of the top reasons your air conditioning system might be leaking water and how the problem can be resolved.
A Clogged Condensate Drain Line
This is, by far, the most common culprit behind a leaking A/C unit. Your air conditioner pulls moisture from your indoor air, and this moisture, called condensate, is collected and channeled safely out of your home through a dedicated drain line. Over time, this line can become clogged with a mixture of dirt, dust, algae, and mold that thrives in the dark, damp environment. When this blockage occurs, the water has nowhere to go, and it backs up into the drain pan and, once the pan is full, overflows into your home. If you need help clearing your condensate line, make an appointment with an HVAC professional. An HVAC technician has specialized tools to force out even the most stubborn clogs safely and effectively.
A Dirty Air Filter
Did you know that a dirty filter does more than just reduce your indoor air quality? It can make your A/C leak. This is because a clogged filter restricts the flow of warm air over your system’s evaporator coil. Without this warm air, the refrigerant in the coil gets too cold, causing the coil’s surface temperature to drop below freezing. Moisture from the air then freezes onto the coil, encasing it in a block of ice. When your system cycles off, this ice melts. The sudden deluge of water can completely overwhelm the drain pan’s capacity, causing it to overflow.
If you suspect that a dirty filter could be the cause of your leak, check your air filter. If it’s gray, dusty, and clogged, replace it immediately. Most standard 1-inch filters should be replaced every 3 months. If you have pets, live in a dusty area, or have family members with allergies, you should check it monthly.
Low Refrigerant
Just like a dirty air filter, low refrigerant levels can cause your evaporator coil to freeze over. Refrigerant is the substance that absorbs heat from your air. When the level is low, it changes the pressure within the system, causing the evaporator coil to become excessively cold. This leads to the same freezing-and-melting cycle described above, resulting in an overflowing drain pan. It’s important to note that refrigerant doesn’t get “used up” like gasoline. If you’re low on refrigerant, it means you have a leak somewhere in the lines.
This is not a DIY job. Handling refrigerant is regulated by the EPA and requires a certified technician with specialized equipment. An HVAC professional will first need to find and repair the source of the leak so that the solution does not harm the environment or your family. Once the leak is repaired, the technician will recharge the system with the correct amount of refrigerant.
A Damaged or Rusted Drain Pan
The drain pan sits directly underneath your evaporator coil to catch condensation. If your system is older, this pan, which may be made of metal, can rust through over time. Newer systems often use durable plastic pans, but these can still crack or become damaged. When the pan is compromised, water will leak through it, bypassing the drain line entirely.
Replacing a drain pain is often a complex job that requires dismantling parts of the air handler. For example, the evaporator coil may need to be lifted or removed to get the old pan out and the new one in. To ensure it’s done correctly without damaging other components, it’s best to leave this air conditioning repair to a qualified technician.
A Broken Condensate Pump
If your indoor A/C unit is installed in a location below the level of your home’s exterior — like a basement — it can’t rely on gravity to drain the condensate. In these cases, a small device called a condensate pump is used to collect the water and actively pump it outside. If this pump breaks, malfunctions, or loses power, it will stop removing water, and its reservoir will quickly overflow.
To determine if the condensate pump is the reason your A/C is leaking water, you can perform a simple test by pouring a small amount of water into the pump’s reservoir. This should trigger the float switch and activate the pump. If it doesn’t turn on, check to make sure it’s plugged in and the outlet has power. If it has power but still won’t run, the pump has likely failed. A professional A/C installation team can make sure the new pump is the correct size for your system and is wired and installed safely.
Improper Unit Installation
An air conditioning system needs to be installed perfectly level to function correctly. If the entire air handler unit was installed at an incorrect angle, water can pool at the wrong end of the drain pan and spill over the edge before it ever reaches the drain line.
Correcting the alignment of an entire air handler is a significant job that absolutely requires a professional. A technician will need to reposition the unit, possibly install new supports or pads, and ensure it is perfectly level so that gravity can do its job and direct the condensate where it needs to go.
Get Your Leaking Air Conditioner Fixed Right Away!
If your air conditioner is leaking water, our experienced technicians are here to diagnose the problem and get your system back in tip-top condition. We have the tools and expertise to handle everything from simple drain line clogs to complex refrigerant leaks. So, give us a call today and enjoy the peace of mind that comes with knowing your air conditioning maintenance services are in excellent hands.