How to Install a Portable AC in a Sliding Window (Easy Guide)

While a central AC unit may be suitable for your home, it can be costly. Plus, specific regulations may even restrict you from installing one in the first place.

If you’re looking for a low hassle way to keep cool and save money, then you should consider investing in a portable air conditioner for your home.

Apart from being inexpensive, it’s relatively small and easy to install, too, especially if your home is surrounded by sliding windows.

Follow this guide for a step-by-step on installing a portable air conditioner in sliding windows (and other common window types).

A Step By Step Guide on Installing A Portable Air Conditioner

Now that you know your home’s window type(s), you’re ready to tackle this guide on installing a portable air conditioner.

How to Install Portable Air Conditioner in a Horizontal Sliding Window
  1. .Open the sliding window. Put the sealing plate into the opening. Adjust the length, so it fits the window snugly.
  2. .Screw or bolt the plate to keep it fixed. Close the window.
  3. .Install the exhaust pipe on the portable AC. This is usually located at the back of the machine.
  4. .Place the flat exhaust pipe nozzle on the opposite end of the exhaust pipe.
  5. .Extend the exhaust pipe and place the nozzle on the sealing plate.
  6. .Plug the unit and turn your AC on.
How to Install Portable Air Conditioner in a Push Out Window
  1. .Install your window kit or place a plexiglass cover as needed.
  2. .Open the window. Attach the latch to the window and the frame.
  3. .Use retainer clips or twist clamps to secure the insert to the frame.
  4. .Caulk or apply weatherproof stripping to the junction of the casing and the window frame. This will help prevent any air or water leak.
  5. .Attach the hose to the insert and turn your portable AC on.
How to Install Portable Air Conditioner in an Awning Window
  1. .Install your window kit. If it doesn’t fit your window, you can make a plexiglass shield according to the size of your window and hose.
  2. .Open the window and place your plexiglass shield. Use a retainer clip to keep it in place.
  3. .Create a seal with caulk or weatherproof stripping.
  4. .Attach the hose and seal the gaps between it and the plexiglass.
  5. .Turn your portable A/C on.

What is a Window Kit?

Portable AC Window Kit

A window kit, also known as a venting kit, is a vital part of installing a portable air conditioner. It helps vent out the hot air so that it won’t be trapped in the room.

Without it, your room will remain warm even if you have the AC on blast!

Apart from venting out the hot air, the window kit can help remove the room’s moisture. This makes the room even cooler since the kit eliminates the moisture that cancels out the AC’s cooling effects.

Given the many types of windows, you need to know how to install a window kit for a portable air conditioner properly. The general rules are:

  • Placing the kit at the bottom for a window with an up-and-down operation
  • Putting the kit at one side (and extend it until it covers the entire window height) for side-to-side windows

What if the Window Kit Doesn’t Fit My Window?

If the kit isn’t big enough for your window, then you will need to create something (out of plywood or plexiglass) to cover the remainder of the opening.

Since this can be troublesome, it’s best to do proper research before buying a portable A/C and window kit. That way, you don’t have to end up spending time over a DIY cover just to make your ill-fitting window kit work.

Different Types of Windows (for AC Installation)

The first thing you need to know before installing your portable A/C is the type of window you have at home.

Here are some of the most common examples:

Portable AC for Different Window Types

Sliding Window

As the name suggests, this window opens sideways. It’s large and easy to operate, and as such provides good lighting and ventilation. Although it’s suitable for below-ground rooms and basements, it does not make a tight seal compared to other window types.

Push-Out Window

A push-out window is opened from the center – just like a French door. Since it doesn’t come with a vertical frame, it provides uninterrupted views of the outside. You just need to ensure you keep it secure so it won’t blow out on a very windy day.

Awning Window

An awning window is opened with the use of a crank, which then pivots at the top of the window sash. It’s often placed at the top, bottom, or side of a picture window for ventilation. Although it’s both functional and decorative, its open-out design means it’s not suitable for high-traffic areas such as walkways.

Casement Window

Like awning windows, casement windows open out – although they pivot from the side hinges. As they lack a frame or muntin bar, they provide uninterrupted light – as well as ventilation. They also provide a seal for better energy performance. But just like awning windows, they shouldn’t be placed near walkways.

People Also Ask (FAQ)

Can you install a portable air conditioner without a window?

Yes. You can vent your portable A/C without a window through the ceiling, wall, or fireplace.

Homes with drop ceilings, for example, may use the existing ductwork to vent the hot air away from the A/C unit.

Homeowners may also cut a hole through the wall and build a small wooden frame for the vent. This, however, is recommended for those who want a more ‘permanent’ portable AC – and those who don’t live in a cold, wintery area.

Another option for venting is a fireplace that has a chimney leading to the outside.  You can vent your AC through the hatch – though you need to run the hose as far as necessary.

Are portable air conditioners quieter than window units?

Yes. The SereneLife SLPAC portable AC, for one, only operates at levels ranging from 55 to 57 dB. It’s a few notches lower than the standard AC units, which typically operate at 60 dB. We also reviewed a bunch of ultra-quiet portable AC units in this guide.

Can you put a window air conditioner unit in a sliding window?

Yes. You just need to install a window kit/sealing plate so that you may vent the hot air away from the portable AC. This will also keep the moisture – which neutralizes the cooling power of the AC – at bay.

Is portable AC better than a split AC?

Yes. For one, they’re cheaper than window units or a central AC unit. It’s also a more economical choice, especially if you only need spot cooling – meaning you only need to ‘cool’ a room or two. With this method, you can avoid an expensive electric bill – which is usually characteristic of homes with a centralized AC unit.

A portable AC is also very compact, which means it’s excellent for smaller rooms or houses. It doesn’t occupy much of your window, so you get to maintain their wide viewing space or ventilation capacity.

You also don’t have to worry about housing restrictions with your portable AC. If your apartment or building doesn’t allow central or mini split AC units, you can circumvent this restriction with the help of a portable unit.

Most importantly, portable ACs do not only cool your home – they help dehumidify it as well. This is particularly good for homeowners in humid areas, where the humidity can be very uncomfortable. Even if you don’t need cooling, you can use your portable AC’s dehumidifying mode.

When should I get an HVAC technician to do an installation?

While you can easily install a portable AC by yourself, you may consider getting an HVAC technician for the following reasons:

  • You want to make sure your portable A/C works efficiently
    While it’s easy to install a portable air conditioner in an awning window, you will need to ensure it is adequately sealed for it to work efficiently. If this sounds like too much of a hassle for you, then an HVAC technician may come in handy. That way, you don’t have to worry about air or water leaks that may compromise your AC’s cooling performance.
  • You want fast installation.
    If it’s your first time to do portable air conditioner casement window installation, then you may probably end up laboring over it for a couple of hours. If you want a quick fix – especially in the hot weather – then you will need the assistance of an HVAC technician.
  • You want to avoid damages
    If you’re not confident about your DIY skills, then you’re better off with a professional. Given their skill and experience, they will be able to install your portable AC without any fuss.


A portable AC provides affordable, on-demand spot cooling – while dehumidifying your home at the same time. Given these benefits, it’s an excellent investment if you don’t have a central AC unit.

Learning how to install a portable air conditioner in a sliding window – or in any other window type your house may have, is a great way to brush up on your DIY skills and save some money.

Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.