Updated at: 27-09-2022 - By: Sienna Lewis

When you notice water dripping from your window air conditioner, many consumers instinctively dial a repair service. Condensation from your air conditioner is quite acceptable and even expected in some cases. Condensation may form on your air conditioner’s coils if you have the thermostat set to a low temperature when the weather is particularly hot and humid.

Your AC unit should be checked up by an HVAC repair firm to ensure it isn’t overproducing or leaking too much condensation. AC units should only produce condensation when they are running, as a general rule of thumb. Within a day or two, this condensation should be gone.

A huge problem arises when your air conditioner begins to leak a significant amount of water into your home. First and foremost, shut down your air conditioner and contact a repairman. You must act quickly to prevent more damage to your house and costly repair costs from water damage. You may have one of the following issues if your AC unit is leaking.

1. Window AC Unit Is Leaking Water Due To Condensation Drain Blockage (Most Common Cause)

As many as one out of every three or even two of these occurrences is caused by a clogged condensation drain on the window air conditioner. Fortunately, this is the most straightforward source of leakage.

A window air conditioner’s primary function is to remove water vapor from the atmosphere (works like a dehumidifier). The condensation pan, which is placed at the bottom of the window air conditioner, collects the moisture that has been removed from the air. In order to keep the overflow pan and drainpipe connected, a condensate drain was installed.

Window air conditioner leaking water inside - fix - YouTube

The condensate drain is partially or permanently clogged, which is why your window AC is leaking. Condensation drains can become clogged by everything from dirt and mold to leaves and even dead animals like bees. As a result, water cannot be expelled from the condensate pan, resulting in a spill. You’ll see water dripping or leaking from your window unit, depending on where the unit is leaning, if the drain is partially or permanently blocked.

Getting rid of a clogged condensate drain is a cinch. Remove the obstruction. The condensation drain can be found by opening the backside of the window air conditioner. A needle, a toothpick or a thin screwdriver can be used to free a blocked drain by placing the instrument into the drain and wriggling it back and forth.

It’s possible that this is all you need to do in many circumstances Check for leaks by turning on the window air conditioner. A window AC unit at 100% capacity should be able to drain surplus water even if it’s hot outside and you have 60% relative humidity.

2. Water Is Leaking Through A Hole In The Condensate Pan (Older Units)

If your window air conditioner has been running properly for more than a decade and is only now beginning to leak, you may have a damaged condensate pan problem. This is a common cause of water leaks in older units.

The condensate pan is responsible for collecting the water that the window air conditioner extracts from the air in the room. The capacity of this pan, which is found at the base of window air conditioners, is less than two pints. Condensation drains collect water from the unit and direct it to the drainpipe in a well-functioning system.

The condensate pan must be intact to prevent window air conditioner leakage. For each minor dent or hole, the water will begin to seep from that area. Newer pans can be damaged by an unexpected puncture during installation, whereas older 10+ year old pots can be damaged by rusting and corrosion.

There is no way around this; the pan must be replaced if it has a hole or dent in it. To be honest, new condensate pans aren’t that expensive (around $30). Alternatively, you can use water-resistant adhesive or resin to seal the window AC unit’s bottom gap if you’re doing it on your own.

If your condensate pan is corroded in an older unit, you may need to close more than one gas valve. You may have to remedy this leaky window AC problem multiple times because of the deterioration (progressive corrosion).

Buying a new pan or even a whole unit may be the best option in these circumstances. This is the place to go if you’re looking for the best energy-efficient window air conditioners.

3. Frozen Evaporator Coil Causes The Window AC Unit To Leak (Due To Dirty Air Filters)

The air filters should be cleaned at least twice a year for good reason. A frozen evaporator coil can be the result of filthy air filters. Thus, the window air conditioner will begin to leak and even blow hot air in reverse (instead of cold air).

Filters in window air conditioners remove bigger particles like hair, dust, bugs, and so on, much like any other filter. All of these contaminants, as we’ve seen before, might result in condensation drain leakage. In order for the window air conditioner to perform correctly, the air filters must be cleaned or replaced regularly.

Leaks caused by clogged air filters: The refrigerant coil will be obstructed if the air filters are not cleaned (even up to 10 percent lower CFM might be problematic). The purpose of the refrigerant coil is to lower the temperature of the hot air that comes in. It will become gradually colder and, if the air filter restricts airflow, it may freeze over if it does not receive as much hot air as predicted. When the ice in your window AC unit melts, it can spill up to a pint of water at a time.

It’s not as simple as it sounds to fix a clogged air filter. Isn’t it just a matter of “changing the filters”? The refrigerant coil is most likely still frozen if you’ve previously noticed leakage. This can be remedied by changing the air filter, but you’ll need a towel just in case. During that time, the remaining ice will be oozing out of the window air conditioner. Be sure to stay close to the unit until the coil is completely unfrozen and the unit stops leaking to prevent harm to your furniture, walls, or carpet.

Evaporator coils can freeze, posing a danger to the unit’s operation. If you’ve been ignoring the leaky window air conditioner for a while, you run the risk of encountering further window AC difficulties in the future. Keep an eye on the unit even if the leakage problem has been fixed.

Window Air Conditioner Leaking Water Outside? (We Have A Fix) – Upgraded Home

4. Too Low Refrigerant Levels Will Similarly Cause The Coil Freezing-Melting Leakage

Low refrigerant levels are by far the most common source of leaks from window air conditioners. The minor leak can be repaired in the same manner as air filters. You’ll face a bigger challenge if you neglect to replace the refrigerant levels. Find out how to recharge the window air conditioner’s freon here.

The refrigerant plays a crucial role in the operation of air conditioners. The 2nd Law of Thermodynamics dictates that the heat transfer required for an air conditioning system can be generated by expanding and compressing this fluid (thus the compressor).

Due to reduced refrigerant levels, the pressure inside the refrigerant lines will decrease, resulting in water leakage. This will minimize the amount of heat that can be transferred through the window air conditioner. The refrigerant lines will freeze over as a result of a series of reactions. When they melt, you’ll observe water dripping from the window air conditioner into your home (refrigerant coil is located near the indoor side of window AC).

Fixing low refrigerant levels may sound difficult, but with a little technical know-how, you can add freon to the refrigerant lines and get the problem back to normal. You can either follow the steps outlined in the aforementioned article or hire an HVAC professional to assist you. Remember to keep a towel handy in case the ice around the cold coil melts after you’ve refilled the unit with freon and the machine starts working correctly once again.

Use this form to acquire four free estimates from HVAC professionals who have been certified and vetted if you need to get in touch with them.

5. Condensate Pump Is Not Pumping The Water Out Properly (Basement-Level AC Units)

This is intended for households with condensate pumps on their window air conditioners that are located below ground level. An inside window AC unit water leaking is a rare occurrence; most people may easily overlook it, but if you have this identical configuration, the information provided here may be of great assistance to you.

If you have a condensate pump, you’ll normally get one with your AC unit if it’s installed below ground level. Drainage is made easier by replacing the drainpipe with a pump, which actively pushes water against gravity to the surface.

The condensate pump is to blame for a water leak, and it’s easy to see why. A leaking condensate pan is a sign that your pump isn’t pushing the extra water up to the surface.

A damaged condensate pump is perhaps the one repair that you should not attempt to do yourself. HVAC professionals should always check the built-in pumps. Each one is unique, and if the pump within malfunctions, water will leak out.

The condensate pump in your HVAC system has to be replaced to stop water from leaking into your basement. Because these are integrated pumps, it’s not a simple operation.

6. Water Leakage After Window AC Unit Installation

The installation of your new window air conditioner may have gone awry if it started leaking right away. There are numerous reasons for leaking, and the leakage may be the most obvious symptom of an incorrect installation.

If you’ve just moved an existing air conditioner to another window, keep this in mind.

No matter what the cause of the water leakage is, it is always advisable to reinstall the window air conditioner.

If the leaking persists after a new installation, the best course of action is to call an HVAC installation expert and get the problem solved.

Rounding Up Ways How To Fix A Leaking Window Air Conditioner

90% of leakage problems may be solved by addressing these six sources. Remember that a leaky window air conditioner could be an indication of more serious issues.

Condensation drain blockage or frozen fridge coils can be fixed with a few simple fixes.

There may be other issues that need to be addressed if the problem with the leak persists after the repair has been completed.

If you can’t fix your window air conditioner yourself, you may always call an HVAC repairman and fork over the $200+ fee.

How Long Can You Leave a Window Air Conditioner Running?


A vibrating noise is coming from my window air conditioner.

An incorrect installation or the wall where the device was mounted could be to blame for the vibration.

Is there a drain on my window air conditioner if it’s dripping outside?

A: This is common on many systems under humid conditions.

Q: Why does my air conditioner make a loud pinging noise at night?

If the pan is dry, you may hear a pinging noise, which is usually water hitting the condenser. A ping doesn’t necessarily mean that your computer is going down, depending on the model.

Methods To Fix A Leaking Air Conditioner

Even if your air conditioner has a leak, it isn’t a big deal as long as you know what’s coming out of it. People aren’t always aware of their surroundings, so even if the water is merely from your air conditioning unit, it can still be dangerous. Everyone, including yourself, should avoid this at all costs.

It’s our job to make it as simple as possible for you to carry out this task. It can be difficult for some people to complete this task on their own, which is why we’re here to help. We value your safety above all else, so get ready and double check that you and your party are ready to go in case something goes wrong.

When it comes to instances like this, always have a good amount of cash on hand in case you need to buy something. We can guarantee that your air conditioning equipment will perform as well as it did before, and in fact, it will be colder. To fix a leaking air conditioner, simply follow the instructions outlined below:

Preparing for work

Our first priority is to make sure you are capable of completing this activity on your own. The first step is to grab a plastic bag and attach it to the air inlet of your appliance to avoid any leaks.

To ensure that any water or chemicals that leak out of the air conditioner are caught, tape the hoses in place once they are properly installed. You should put as many tapes in the plastic as possible because the movie may fall if it isn’t securely fastened in place. Keep water out of the plastic bag by purchasing a large and strong one.

Method #1. Through exhaling

The most typical cause of air conditioner leaks is when debris gets into the drain pipe and clogs it up. The air conditioner’s drain should not be blocked by the water’s exit pipe.

To begin, you’ll need to get hold of the drain line of the air conditioner and point it upwards so that you can breath into it with your lips. You can protect your lips from the hose by using a tiny handkerchief or even your own hand. Water and debris that have been stuck in the hose will begin to leak into the plastic bag, which will catch any dirt that has been blocking it.

Turn on your air conditioner to be sure there is no more leakage once you have removed all the debris or dirt. Remove the plastic bag and dispose of it immediately so that your appliances aren’t exposed to any filth.

Method #2. Using a vacuum cleaner to remove debris

If the first step was difficult for you, we’ll ask you to use a vacuum cleaner to remove any rubbish stuck in the draining hose. As a result, the first step is to grip the hose and press it against the vacuum cleaner’s nozzle to ensure that all dirt is gathered.

The vacuum should be turned on at high speed and released immediately if you notice that it is sucking too much on the hose. As soon as I turn on the vacuum cleaner, I’m supposed to let go of the cord. Because if you keep vacuuming, the water will get sucked up into the hose and clog it.

Once the appliance’s interiors are exposed to water, it will begin to progressively degrade. To avoid more issues, minimize as much as feasible. After vacuuming for roughly five minutes, unplug the hose and watch the water drain out of the hose’s nozzle. Turn on the air conditioner thereafter to ensure that there are no leaks in the system.


By learning how to fix a leaking air conditioner, we can avoid any potential hazard. Using a hose or vacuum cleaner, you can remove the debris that is causing your air conditioner to leak. To find out how much water you need to remove from your air conditioner, click on the following link. I think that’s about all.