Erin Doman on June 24, 2016 8 Comments HVAC Troubleshooting: Why Your Indoor AC Unit is Leaking Your HVAC unit is something that should be maintained in order to prevent costly repairs. Any leaking or pooling water around an indoor AC unit should be attended to right away. As soon as you discover a leak, be sure to turn off your air conditioner. This can help prevent the water from causing damage to the electrical components of your air conditioner and limit the amount of water damage to your home. A leaking HVAC system can be indicative of a larger problem. Here are 6 things that should be addressed when diagnosing what is causing your HVAC unit to leak. 1. A Dirty Coil One of the major ways your air conditioner works to cool your home is by pulling humidity from the air. The cold evaporator coil of your indoor unit is designed to collect this condensation and drain it away. When everything is working as it is supposed to, the water runs down the coil into a pan which leads to another drain. The ultimate destination of all of this collected water is either outside of the house or into your plumbing drain. One of the most common ways the evaporator coil can malfunction is when it becomes dirty. Once a coil becomes coated in dirt, dust, mold or other debris, the water is no longer bonded as tightly to its surface, and will drip on the ground. The water will also bond with the dirt and grime, mixing it in with the puddles of condensation on the floor of your house. A dirty coil causes problems even for the water it does manage to divert into the proper drain. Any dirt carried through the system is likely to clog your drains. Once the drains are completely blocked, the water has nowhere else to go but back into your home. This damage can be prevented by including yearly inspections and cleanings of your furnace, central humidifies and coils. Well trained professionals will include this as part of a comprehensive annual AC maintenance visit. 2. Clogged Drain Lines Once a clog has been identified, a wet/dry vacuum can be used to clear obstructions. Every four to six months, after ensuring the pipes are clear, pour a mixture of half bleach, half warm water down the drain. This will help keep the drain clear of mold and other growths, as well as assist in dislodging any other impediments for preventative care. If clogged drain lines still continue to be a problem, you may want to consider installing an overflow shut off device on the drain line. This will help minimize future damage by ensuring that your air conditioning unit will automatically shut off if your drain line backs up. 3. A Damaged Overflow Drain Pan Drain pans made of metal or plastic can corrode over time, which can lead to further leakage. Use a flashlight to inspect it for holes or cracks, and replace as necessary. 4. An Icy Indoor Coil Another potential cause of water pooling around an indoor HVAC unit may be an iced over indoor coil. If an icy coil goes unnoticed, melting will often occur rapidly, overwhelming the drain pan and pooling onto the floor, causing many of the same problems as a dirty coil. You can minimize some of this damage caused by an icy indoor coil by running the air conditioning system in fan only mode for a few hours to allow the ice to melt under your supervision, preventing any flooding of the drain pan. There are two primary reasons your indoor coil may have iced up. First, a dirty air filter will prevent proper ventilation and air flow. Second, you may have low levels of refrigerant or a refrigerant leak somewhere in your system. Either one of these factors can cause the temperature around the coils to drop below freezing. You should be washing or replacing your filter at least once every other month during the winter months, and once a month during the summer when your air conditioner is in heavy use. Not only will this help prevent your indoor coil from freezing up, but maintaining clean air filters is a simple way to dramatically increase the energy efficiency and air conditioning capacity of your unit as a whole. If your air filters have been recently replaced, then low refrigerant levels are the next most likely culprit. If this is the case, it is important to bring in a licensed HVAC technician who can to inspect your system to identify the source of a potential refrigerant leak, which can be dangerous if left unattended, as well as to examine your system for any other potential damage caused by the frozen coils. 5. Installation Issues Poor installation practices can present a host of problems, many of which lead to water leakages inside your home. Sometimes, drain pipe fittings have been improperly installed, and loosen over time. This allows the condensation to drain onto the floor. The unit may not be completely level, or if there is too much pressure, this can also result in pooling water on the ground. 6. Water Damage Many condensation line leaks occur inside walls, or in other low traffic areas such as basements and attics. This means that standing water may be present for long periods of time before it is noticed and addressed. Extensive water damage can cost thousands in repair costs. This is another reason it is important to regularly and frequently inspect your HVAC system. Annual HVAC System Tune Up Ensuring that you complete your annual HVAC maintenance work and inspection with a high quality HVAC service company can go a long way in protecting your home from damage and ensuring the optimum working efficiency of your unit. Heating and cooling costs can account for up to half of a home’s totally energy expenditure, and overdue basic maintenance of your HVAC system can drop your heating and cooling energy usage by up to 25 percent. Most customers will more than make up for the upfront cost of hiring a certified HVAC technician for an annual inspection through greater energy efficiency alone. Not only will your HVAC technician be able to pinpoint exactly what to do when your indoor HVAC unit starts leaking water, they will also be able to identify any other issues while they are small and easily addressed. Basic yearly maintenance can ensure that your furnace, central humidifies and coils stay clean, and your drain pipe fittings are secure.
Scott Adams says June 13, 2017 at 3:46 pm I’m glad you talked about having an annual HVAC inspection. I had no idea that I was supposed to get it inspected. It has been getting old, so I’ve been looking for advice. It would make sense to have it checked to make sure it is working efficiently. I’ll start looking for a repairman. Reply
Lisa Neiswender says July 6, 2017 at 4:02 pm Our home was built in 2008 and approximately less than a year ago are furnace which is in our aditc was not working properly, at that time we chose to upgrade to a new furnace which worked great during the winter season. The temperatures are now up to 90 degrees we noticed a couple of bubbles that were forming on our ceiling in a large Loft area. We did stick a pen in the bubble to see if there was any water coming out there was a little amount. I’m asking for help and also information on how much damage this is causing. The furnace is under warranty so I would rather not try to change anything so at voids out the warranty. Thank you so much in advance for any advice. Reply
Julia says August 10, 2017 at 10:14 pm My hvac is leaking water onto the pan tray and there are small pieces of plastic floating in the water. The techs have been out a couple of times to unclog the drain, but it continues to leak water. The installer said that they would not come out again because he did not know what the the problem was. Reply
shafi says September 18, 2017 at 1:30 am 1.DRAIN pipe blocked 2.Uncleaned filter 3.No other blocks in supply air . 4.low gas 5.Indoor leveling Reply
Asif says October 12, 2017 at 3:07 pm My unit have condentions from.wings what could be the problem ? Reply
kitty says November 1, 2017 at 5:34 pm should i shut off the ac until the ac man can come out? if its leaking? Reply
Michael R St Laurent says July 21, 2018 at 8:45 am I had my Diakin AC that leaked water at the evaporator coil after running about 30 minutes. I could suck water out of the drain line and then it would start flowing until it was shut off and started again. Here is what I did to resolve the issue. I cut the drain line as it exits the outside wall and installed a Tee then I installed a 1 foot piece of tubing as a riser to allow air to enter the drain line and wallah problem solved. Air was getting trapped in the drain line making it so it would not flow down the drain properly. Works like a charm after I installed the riser tube. Reply
Barbara Phillips says August 24, 2018 at 10:36 am Hi you have great information. However I have an inside ceiling AC unit. It has been turned off for days. We want to leave it off. I live on the 3rd floor of a 4 story building. The drain pan keeps filling with water! The line was snaked & blown out 3 times and the drip pan drained 3 times as well. Why or where is the water coming into drip pan. Again the unit has been off. Condenser on roof. Help Reply