As the summer heat sets in, a well-functioning air conditioning (AC) system becomes essential for comfort in your home. However, when your AC starts leaking mysterious fluid, it can quickly turn from refreshing to worrying. To maintain your cooling system’s efficiency and longevity, it’s pivotal to understand the types of leaks air conditioners can develop, what causes them and how to safely and effectively address them. Read on to learn how to handle an AC leak like a pro.
The signs of air conditioner leaks differ depending on the type of fluid escaping the unit. The two substances cooling systems can leak are:
Refrigerant is the cooling fluid that makes air conditioners tick. R-32, R-410A, R-454-B and R-134a are popular refrigerants because they easily change from liquid to gas states. Refrigerant cycles through metal pipes and removes heat from the air in a section of your AC called the evaporator coil. The refrigerant changes from a liquid to a gas when it absorbs heat and then turns back into a liquid in a section called the condenser coil when it releases this heat outside.
As humid air flows over the cold evaporator coil, it cools rapidly. Since cooler air can hold less moisture, it becomes fully saturated as it loses heat, causing excess water to condense around the cold coil pipes. Condensation builds up as you use your cooling system, eventually draining into your yard or drainpipe via a drain pan and drain line. This cooling process also helps reduce indoor humidity, creating a more comfortable living environment in high-humidity areas like the southeastern United States.
When your AC leaks refrigerant, you may notice the unit isn’t performing as well. The drop in performance depends on the type of refrigerant leak your cooling system has:
When you have water leaking from air conditioner parts, however, you may notice dripping and pooling around the unit, water stains, excessive condensation, increased indoor humidity levels, a musty smell from mold or reduced cooling efficiency.
Air conditioners can start leaking for several reasons, some of which are easy to fix at home and some that require a more trained hand. Potential causes of water leaking from your AC include:
As air flows over your AC’s air filters, they collect dust, debris and residue over time. Eventually, this accumulated grime stops the air from freely flowing over the evaporator coil. Without a steady stream of warm air to cool, the evaporator coil pulls too much moisture from the already cold air around it and builds up excessive condensation. This condensation can then freeze, thaw out when the AC is inactive and overflow the drainage system as it melts, causing leaks.
If your air conditioner’s drain line is blocked, condensation from the evaporator coil gets stuck in the drain pan, a shallow compartment under your cooling system that collects water before it flows outside. This drain pan eventually overflows as the water has nowhere to go, causing leaks. Drain line clogs happen because of algae and mold growth, dust and debris buildup, pest infestations and pipe damage.
Metal drain pans can rust over time, corroding the material and causing little holes to appear through which water can leak. If the drain pan, seals or connections were improperly installed or damaged through impact, water could escape through cracks or crevices at joining points. Also, if the AC was erroneously installed on a slope, water may leak out of one side when it gets particularly full.
When the refrigerant levels in your cooling system decrease, the pressure inside the evaporator coil drops. This lowered pressure causes the coil to become too cold, freezing the condensation buildup on its surface and creating a layer of ice. When the AC stops working because of ice buildup, or you switch it off for a while, the ice melts and overwhelms the drain pan, causing leaks. Ice can also accumulate because of dirty coils, poor airflow or excessively low thermostat settings.
Refrigerant leaks are often harder to spot than water leaks because they can escape the cooling system as gas. If you do have a refrigerant leak, it’s likely because:
Installation is a pivotal step in getting an air conditioner for your home and should always be done by trusted, experienced professionals. Improper installation can lead to loose or over-tightened connections, wrong pipe sizes, damaged or defective parts, poor insulation, vibrations, erroneous placement and incorrect refrigerant levels that create a pressure imbalance — all of which can cause refrigerant leaks.
If you have a newer air conditioner, its cooling system is likely made of coiled copper pipes. When contaminants in the air mix with water from condensation on the pipes, the reaction creates formic acid, which eats away at copper over time. This corrosion makes tiny holes in the through which refrigerant can escape. While some air conditioners use aluminum to avoid formic acid corrosion, aluminum is still prone to rust, which can cause similar pinholes.
Wear and tear is an inevitable part of every appliance’s life span. Even the best-treated air conditioners will eventually need tune-ups and replacement parts. Rubber seals keep pipe connections airtight, while service valves let technicians adjust refrigerant levels, monitor pressure inside the pipes and perform routine maintenance.
In certain parts of the air conditioner’s refrigerant cycle, rubber seals are exposed to high heat and corrosive chemicals, which can make them brittle over time. If your AC vibrates a lot during use or the seals were overtightened or misaligned during installation, they may wear out more quickly. Refrigerant pressure fluctuations, moisture invasion and clogging debris can all compromise service valves’ longevity.
Your AC’s condenser coil is also susceptible to wear and tear. Because it’s usually facing outside, it is vulnerable to damage from salty ocean air, gardening tools, fertilizers, pets, harsh weather conditions, falling branches and debris accumulation. Vibrations, high pressure from overfilling refrigerant and faulty valves can also cause cracks and leaks in condensation coils.
If your AC is leaking water, you should:
Check to see if your air filters are covered in dust or grime, and if they are, thoroughly clean or replace them. You can clean your air filters by removing them from the unit and rinsing them under warm water until the water runs clear. Allow them to dry completely before reinserting them into the AC. Your manual will indicate where to find the air filters on different AC types and models, although they’re usually located in the return air grille, air handler or behind the front panel of window and portable units.
To prevent leaks from dirty air filters, clean or replace them once a month if your AC is used often or every two to three months if you only use it sporadically. Smooth airflow through new, clean air filters also reduces your monthly utility bills, as your air conditioner can cool the room to your desired temperature using less energy.
If the blockage is loose enough, you can try to unblock the drain line yourself. First, switch off your AC and find your drain line, usually a PVC pipe that drains to the outside near the cooling system’s outdoor unit. Using the cleanout port, inspect the inside of the pipe with a flashlight for visible debris buildup or try flushing water through it, and watch for restricted flow.
Next, use a wet-dry vacuum or a pipe cleaner to dislodge and break up the bulk of the blockage. Then, pour a cup of vinegar or bleach into the drain line to break down any remaining organic material. Let the clog soak in the bleach or vinegar for half an hour before flushing it with water to clear any residual debris.
If the DIY method below doesn’t work, call professional air conditioner services so they can apply their trained hands and specialized equipment to dissolve more hardy blockages. Also, to prevent future blockages and other common AC issues, schedule regular air conditioner maintenance and inspections twice yearly.
Use a spirit level to check that your air conditioner is not slanted to one side due to floor gradients. If your AC has adjustable legs, raise them on one side to level out the drain pan, or place thin pieces of plastic or wood shims underneath one side to counteract the slope if you don’t. Check the gradient using your spirit level to ensure you’ve accounted for the angle correctly. Shims are a temporary solution, so still reach out to your HVAC service provider to install a more permanent level fix.
Turn off your air conditioner and examine your cooling system’s drain pan for signs of disrepair. Consult your AC’s manual to find out where exactly your drain pan is located and how to access it. In central ACs, the drain pan is typically under the evaporator coil in the air handler, and ductless mini-split systems usually have a cover you can lift or unclip. Remove the drain pan’s access panel and investigate for signs of leaking, warping, cracking or pitting using a flashlight if needed.
Refrigerant leaks can lead to water leaks. If you’ve crossed blocked drain lines, dirty air filters and uneven drain pan slopes off your list of causes, your air conditioner likely has an active or passive refrigerant leak that’s freezing the evaporator coil condensation. In that case, you’ll need the help of an HVAC specialist.
If any parts you examined were damaged, worn, corroded or frozen, you’ll need a technician to service your air conditioner and replace any unsalvageable fixtures. With routine maintenance twice a year, technicians can find and fix small problems like slightly worn seals or minor corrosion before they escalate into full-blown leaks that require new parts or complete AC unit replacements. Your system will also run more efficiently and cost-effectively with regular tune-ups.
If you have an air conditioner refrigerant leak, you should:
It’s wise to stop using your cooling system the moment you think you have a refrigerant leak, as prolonged operation can worsen the issues your AC already has. Unplugging the unit also helps prevent the compressor from running dry, which can lead to significant damage and repairs. Additionally, turning off the power creates a safer environment while you wait for a professional technician to assess and resolve the issue.
Check for visible damage to the condenser coil, oily spots, signs of pipe corrosion, frost or ice on the evaporator coil and brittle or broken seals and valves. If you spot any of these symptoms or hear a hissing noise, your water leak is probably due to refrigerant levels dropping and freezing the evaporator coil and needs professional attention. Technicians also have safe, reliable, specialized testing methods to detect defects you could miss with the naked eye.
If you’ve identified signs of a refrigerant leak, call a professional HVAC technician to help. They have the expertise and specialized tools to accurately diagnose, measure and repair refrigerant leaks safely. Trying to fix refrigerant issues without proper training can lead to health concerns, further damage to your air conditioner or environmental hazards.
For prompt, expert air conditioning leak diagnostics, repair and maintenance services, you can rely on Strada Air Conditioning & Heating. We’re committed to providing our clients across the southeastern United States with exceptional quality products and professional assistance every time. Our convenient routine maintenance plans come with many convenient, cost-effective perks to keep your home cool, comfortable and leak-free year-round.
Since 2003, we’ve strived to provide industry-leading, gold-standard service wherever we go. Browse our client reviews and testimonials to see how our prompt service quickly resolved their AC issues and improved their overall indoor comfort. We’d love to help you experience the same relief. To join the many homeowners who trust Strada Air Conditioning & Heating for all their HVAC needs, contact us online today.
Joe Strada, owner of Strada Electric, Security & Air Conditioning, started working at the young age of 14. He’s never attended college, but he has spent his life dedicating his time and energy to his trade and providing high-quality services to his customers. At 19, Joe started working at a well-known air conditioning company and developing his commitment to excellence. He has state certifications in electric, plumbing, air conditioning, residential building and general contracting. During his years of training and experience, Joe noticed a sincere need for a dependable electrical contractor in Florida who embodied the same dedication to customer service in which he believed. In 2003, Joe co-founded Strada Electric, Security & Air Conditioning. Since then, the company has been in the business of providing peace of mind to customers. We offer expert electric, security and air conditioning solutions for homes and businesses, leveraging our experience to deliver professional and responsive service with reliability and respect.
