What Causes My AC to Leak Water?
Have you noticed that your AC system is leaking water inside or outside your house and you’re not sure why? Water leaking from the AC condenser unit outside your house usually isn’t a cause for concern. Water leaking from the indoor part of your AC system, on the other hand, isn’t normal and usually means there is an issue with the condensate drain system.
Clogged Drain Pan or Condensate Drain Pipe
Condensation is a natural result that sometimes occurs during the air conditioning process, which is why the indoor part of your central AC has a condensate drain system. If the air in your house is fairly humid, it can almost instantly get cooled down to its dew point when it meets the AC evaporator coil. The result is that the water vapor in the air then ends up changing states and condensing into liquid on the coil, and this process is how air conditioning helps to dehumidify the air inside your house.
Under normal circumstances, all of the water that forms on the evaporator coil drains away. Directly below the evaporator coil is a drain pan that collects the water dripping off the evaporator coil. The water then flows through a series of drain pipes that either connect to the home’s plumbing drain system or lead outside. The issue is that the warm, moist environment often leads to mold and algae growing inside the drain pan and/or drain pipes. Over time, this can result in a clog forming that prevents the water from draining away. When this happens, the water eventually backs up to the point that the drain pan overflows, and you end up with water leaking out of the air handler onto the floor below it.
A clog in your AC’s condensate drain system isn’t necessarily a dire issue, but it can cause water damage to the flooring around the air handler and also create a risk of mold growth in the nearby areas. You can sometimes fix a clogged drain pan yourself if your air handler has an access door. Fixing a clogged drain pipe normally requires the help of a professional HVAC technician. You’ll also need to hire a technician if your air handler doesn’t have an access panel since the only way to access the drain pan is to cut a hole in the air handler and then patch the hole once the pan has been unclogged.
Leaky Drain Pan
Most drain pans are either plastic or metal, and either type can sometimes develop a leak over time. Plastic drain pans can eventually crack and start leaking, whereas metal pans can end up leaking because they rust through. It is sometimes possible for a technician to patch a plastic drain pan so that it no longer leaks, but a rusted-out metal pan will usually need to be replaced. The only issue with metal drain pans is that they are sometimes welded onto the evaporator coil and can’t be removed. In this case, the only way to fix the leak is to replace the evaporator coil.
Frozen Evaporator Coil
There are a few different issues that can lead to condensation freezing on the evaporator coil before the water can drip off into the drain pan. Whenever this happens, you’ll realize fairly quickly since your AC will quickly start putting out hot air once the coil freezes. The only way to get your AC to start cooling again is to shut it off and allow enough time for all of the ice to melt. Once the coil starts to freeze, more and more ice will continue to form. If there is a large buildup of ice, all of the water that forms as the ice melts can sometimes be more than the condensate drain system can handle. This can then lead to water leaking out of the air handler as a result of the drain pan overflowing.
Uninsulated Refrigerant Line
Condensation can also form on the outdoor part of your AC system, leading to water dripping out of the condenser unit. The section of the cold refrigerant line located inside the condenser usually isn’t insulated, which is why you’ll often have condensation dripping out of the unit. This really isn’t a big deal since it has a negligible effect on how well your AC performs. On the other hand, the rest of the cold refrigerant line from where it exits the condenser to where it enters the air handler inside must be fully insulated. If it’s not, the refrigerant will absorb lots of heat before it reaches the evaporator coil, and the AC system won’t work nearly as effectively.
If the part of the pipe that’s exposed outside the house isn’t insulated, it will constantly “sweat” due to condensation forming on it, and you’ll end up with water on the ground around the condenser unit. In this case, you definitely want to have the refrigerant line reinsulated since it will help improve the efficiency and effectiveness of your AC system.
Nacogdoches Sheet Metal, Plumbing & Air Conditioning, LTD. is a veteran-owned HVAC company that is ready to handle your air conditioning and heating repair, maintenance and installation needs. Our team has years of professional experience and can help if your AC is leaking or you need any other comfort service. If you’d like to schedule a service call in the Nacogdoches area, contact us today.