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What To Do if a Window Air Conditioner Has No Drain Hole?

Whether you have a new window air conditioner or a hand-me-down, they can be tough to maintain when they get older, especially if you’re new to taking care of them. For those who have one, yours may not have a drain hole, which leaves many people wondering what they should do.

If your window air conditioner has no drain hole, ensure it is supposed to. After that, clean it or consider getting it repaired. Try to refrain from creating a drain hole yourself, as it will void any warranty on the unit. 

Let’s take a closer look at why your window air conditioner may not have a drain hole and what you can do to repair it if needed. 

Why Can’t I Find a Drain Hole on My Window Air Conditioner?

You may not find a drain hole in your window air conditioner if it is plugged, rusted, or dirty. A new unit won’t be dirty or rusty, but if your unit has been used for a while, you may be dealing with a blocked drain hole. 

Start by thoroughly cleaning your window air conditioner to ensure the drain hole isn’t blocked by rust or debris. This can happen with units after they have been used for a while because a lot of water passes through the hole. With the unit sitting in your window, there is always a chance that dirt or debris can make it inside the unit. 

If you do find that the drain hole is blocked, then you should take the time to clean it thoroughly and see if that helps it drain properly. 

Rusting is also natural when dealing with water and metal parts. So, make sure you are cleaning your unit regularly to avoid rusting as much as possible. 

If your unit does happen to rust, there are ways to get rid of it. For instance, white vinegar is an effective solution, although it must be soaked in the liquid to work properly. There are also sprays that help break down rust. Whichever method you choose, eliminating rust can help your unit work better and let you find the drain hole. 

Another possibility is that your drain hole may be plugged. This often happens for units that hold and reuse water rather than draining. These units are mostly window air conditioners that work without draining, which we will talk about later. 

If your drain hole is plugged, clogged, or nowhere to be found, it may be tempting to drill a new one. This isn’t recommended as it will ensure your unit is no longer covered under warranty. It is best to return your unit to the manufacturer or get it repaired. 

Do All Window Air Conditioners Have Drain Holes?

Not all window air conditioners have drain holes. In fact, most modern units don’t come with one. These units work by reusing the water they would otherwise get rid of. 

Traditionally, window air conditioners have drain holes that allow the water to drain, but most units made today do not. That’s because manufacturers have found a way to put the water to good use. 

The water falls into a tray where it is stored until it is needed. Once it is needed, it’s slung onto the condenser. 

This way, not only does the water keep the unit from overheating, but it also allows an otherwise wasted component of the design to be recycled. 

Most modern units still have a fail-safe drain hole located on the side of the unit. However, it’s commonly plugged as these units are not meant to drain. So, your unit may have a drain hole, but it could be plugged in until it is needed. 

Where Is a Drain Hole Located on a Window Air Conditioner?

The drain hole is located on the bottom of traditional window units and the side of modern units. The location varies depending on the drain hole type. When all the water needs to drain, the hole will be on the bottom of the unit. Otherwise, it will be on the side to prevent the unit from flooding.

As discussed, older units are meant to drain excess water from inside the unit. So, this requires a drain hole on the bottom of the unit. Otherwise, there would be water sitting in the unit until it rises high enough to drain. 

On more modern units, you’ll find the drain hole on the side of the unit. Modern window air conditioners will collect the water in a pan and reuse it to keep the system from overheating. So, the drain hole is on the side in case the pan overflows with water. 

Having the drain hole on the side makes sense for modern units as they reuse the water, but it’s important that you know where the drain hole is located. If your unit were to overflow, water would come out of the drain hole. So, you should place something under the hole to catch any excess water if it is going to drip inside of your window

Whether it’s a modern or traditional setup, the drain hole will be small on any window air conditioner. They usually don’t produce enough water to require a large hole. Because of this, it can be hard to find the drain hole, especially if it’s clogged, covered, or rusted. 

So, keep your eyes open for a small hole on the bottom or side of the unit, and make sure it stays clear so the unit can drain properly. 

Final Thoughts

If you have trouble finding the drain hole on your window air conditioner, you’re not alone. Not only are these holes hard to see, but they may also be covered in rust and debris from use over time. 

The best way to find the drain hole is to clean your unit thoroughly and take the time to inspect it. Remember that not every unit will have a drain hole. So, make sure you check with the manufacturer for details. 


  • Steve Rajeckas

    Steve Rajeckas is an HVAC hobbyist with an avid interest in learning innovative ways to keep rooms, buildings, and everything else at the optimal temperature. When he's not working on new posts for Temperature Master, he can be found reading books or exploring the outdoors.

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