My Air Conditioner is Leaking!

HVAC Bluffton SC air conditioner leaking

5 Simple Causes (and Solutions!) for a Leaking HVAC Unit

You come home from work. The temperature rose to 100 degrees today. Or at least it felt like it did! Once at home, you kick on the AC, dreaming of watching TV in the cool air. But, you soon find that the AC has been on for 30 minutes, and it’s not as powerful as it was yesterday. You aren’t able to cool down. You investigate the problem and find the AC is leaking!

What do you do?

As you panic, your brain can only think of one solution. Call the AC guys!

But wait! You have other options. Before you call a professional, do a little investigating. You just might be able to take care of the issue for little or no cost!

We’re going to talk about when you should (and when you shouldn’t) call a professional HVAC contractor to fix a leaking unit.

How does an AC unit work?

Before learning the causes of an AC leakage, it is best to know the functions of an AC unit for better troubleshooting.

To break it down to the short and sweet: three functions keep your AC running. The evaporator, compressor, and condenser. The evaporator is inside your house in the Air Handler unit, while the compressor and condenser are outside.

The Process

The air in the house moves into the AC unit and across the evaporator. The evaporator contains a chemical called refrigerant, and it absorbs the heat from the hot air, changing it from a liquid state to a gas state. The heat extracted from the air allows it to be colder. The refrigerant, in a gas state, runs through the compressor (located outside the house) that compresses it into a higher temperature and higher pressure.

Once the compression part is over, it passes through the condenser, which condenses the refrigerant into its liquid form again while excess heat exits the unit outside your home (where it belongs!). That liquid-form refrigerant returns to the evaporator and goes through the whole process again.

Common Causes of AC Leakage

Now that we’re familiar with the basics, let’s talk about what you can do to prevent or repair leaks without unnecessarily whipping out the credit card.

1. An Overflow Drain Pan

The first and easiest item to check is the drain pan. The drain pan can be found directly underneath the Air Handler unit. After locating it, check if it is overflowing with water. If it is, you need to figure out why.

The excess condensation produced in the evaporator coils filters out onto the drain pan. It helps regulate the air inside the unit. But, if you find it overflowing, it’s time to replace it.

You might be able to patch it up if you see any cracks in the drain pan. A product such as epoxy glue comes in handy for that. But, because you might not want to damage the unit further, it is best to replace it right away rather than repairing it.

You can find drain pans in your local hardware store or even online, just be sure to buy the right size!

2. Dirty Air Filters

During those hot summer days, you barely think how much of output your AC pushes out to make you comfortable in your home. The workload is more than doubled!

But, once the output becomes weak, unable to cool you, you should investigate the problem by inspecting the air filters. They are the one item that most people forget to check, but they are the easiest to replace (or clean for reusable filters).

In the summer, because of the higher output, the filters should be inspected every month; in the winter, every three months. Once a filter is clogged, it can quickly freeze the evaporator coils.

Once they thaw, it drips water into the unit. That water collects onto the pan, overflowing it. Replace or clean dirty filters so the air can flow correctly through the different parts of the AC unit.

To clean a reusable filter, you can use household products such as dish soap and water, or better, vinegar (it kills any bacteria inside the unit). Gently scrub them. After cleaning, put them back.

Dirty AC filters
Air Conditioning leaking guide

3. Clogged Condensate Line

The condensate line is connected to the drain pan. The condensation collected in the pan is drained through the condensate line which filters it into a drainpipe, keeping the airflow going.

Mold or algae can grow inside if not cleaned every few months. The bacteria causes the water from the drain pan to get backed up. The water then returns to the drain pan, overflowing it. If your unit is equipped with an overflow switch; it will automatically shut off the AC once the drain is full.

To clean the clog, you can use a wet/dry vac. Attach the hose part of the vacuum to the condensate line and start the machine. The vacuum will collect any mold or dirt inside the pipe.

4. Improper Installation

It never occurs to most people that their equipment might not have been installed correctly.

If the condensate drain line was not tightly connected to the unit, it could be the cause of your leak. Slowly, it will loosen and disconnect, and the water will pour out inside your house. If you find this is the problem, you can try to fasten the pipe to the unit, but our recommendation is to call a specialist because they have the right tools to secure the line.

air conditioner leaking HVAC Service

5. Damaged Condensate Pump

The condensate pump regulates the water levels that are circulated in the HVAC system. When damaged, it holds the water in and eventually overflows. Operating it after its malfunction can be expensive in the long run, as you may need to repair or replace it. Call a professional to take a look at it, and they can suggest which repairs are necessary to fix the leakage.

If you find the pump is just dusty/dirty, try cleaning it with household products. No need for a professional!

Once the area is clean, if you want to go a step further you can remove the fan cage with a wrench and screwdriver. Clear dirt, grass, and leaves from the inside of the unit with a shop vac.

Just a reminder, before you inspect the Air Conditioning unit, make sure to turn it off for your safety!

If you are in need of air conditioning services, we cover all HVAC services in Bluffton, Hilton Head, and Lady’s Island.

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