The last thing you want to see when you enter your home after a long day at work is a steady stream of water falling from a badly stained ceiling into the middle of your living room, coming from an air conditioner above. Not only is it making a mess, a house AC unit leaking water can cause serious and expensive damage to your home's infrastructure, not to mention creating a prime environment for mold to grow. When you start to see water running where it shouldn't, it's imperative that you stop the AC leak immediately to prevent further damage.
The first thing you need to understand when your air conditioner is leaking is where the water is coming from. When the unit is working correctly, water condenses on the air conditioner's cooling coils, dribbles down into a collection pan, and then drains away down a pipe. You don't know the water's even there because you never see it.
If you do have a wall AC unit leaking water inside, the most likely cause is that the drain on the appliance's condensate drip pan, or the drain line, has gotten clogged. It's a common occurrence that can happen without periodic maintenance, and typically is caused by a medley of dust, mildew and bacterial slime.
You could call a professional to come help you with a drippy air conditioner. But that could cost a big chunk of change, and during a hot summer it might take a few days before a service person can come to your house to take a look. In the meantime, you'd either have to turn off your AC to stop the leak or start using buckets to catch the falling water.
However, this problem is easy to fix and requires no special skills. Read the instructions below to fix your AC water leak yourself.
Instructions to Stop the AC Leak
If you try to remove the plastic drain piping from the pan outlet but find that it's glued in place, you still have a path forward to resolve your leak. You'll need to saw off some of the PVC pipe and then make a new detachable connection.
Additional Supplies Needed
Because periodically cleaning the condensate drain and pipe is cheaper than cleaning up a costly leak, it pays to make the job easier by installing a simple clean-out using a T-joint and a snugly-fitting pipe cap. Just make sure you do not install the T-joint downstream from the condensate trap. Just like a sink trap, condensate traps fill with water. This protects your AC system's efficiency by preventing cooled air from blowing away down the drain pipe.
Window air conditioners can be another source of water infiltration, especially if they aren't installed properly. If you see water coming into the house from your window unit, the first thing to do is check the angle of its posture in the window. The appliance should be angled slightly downward on the outside of the window, so that the water will accumulate at the back of the drain pan and drip safely outside the house.
If the air conditioner is installed at the proper angle but you're still having a water problem, make sure that the filter and coils are clean, since if the unit is not kept in good condition the condensation can accumulate and migrate to inconvenient places – such as the inside of your house. Finally, check the condensation pan itself and its drain to make sure there's no clog or debris blocking the water from getting out.