How to Vent a Portable Air Conditioner

A portable AC exhaust hose fed through a window covering.
What You'll Need
Window venting kit (including exhaust hose and connection adapters)
Plexiglass or plastic visqueen curtains
Plastic sheeting
Measuring tape
Utility knife
Drywall or masonry saw (in some cases)
Padding and/or weather stripping
Soapy water

Beating the heat in a room or building without a central cooling system is a lot easier once you know how to vent a portable air conditioner. These AC units operate using the same technology as conventional air conditioners, but they are designed for mobility. They are generally lightweight or have wheels. While these air conditioners are generally used in situations without extensive refrigerant plumbing and ductwork, there is an opening at the back where the exhaust heat escapes that needs to be vented properly. Obviously if this heat is allowed to escape back into cool room, it will practically render the air conditioner useless. These units are most readily vented through windows but can be vented through walls, floors, or ceilings where necessary. All you need to know is how.

Step 1 - Determine Location of Exhaust Opening

As mentioned previously, the easiest and most logical location for a portable air conditioner exhaust opening is through a window. However, if the room does not have windows, you must consider other options. To effectively cool the room, you may have to cut a vent hole in the wall, floor, or ceiling.

Step 2 - Determine the Configuration

For horizontal or vertical sliding track windows, venting portable air conditioning exhaust is almost effortless. Your unit should’ve included a window venting kit at no extra cost at the time of purchase. If the original kit has been lost or damaged, a replacement can be ordered from the manufacturer. It will contain a sheet of plastic with a hole in it, a long corrugated tube, and adapters to make airtight seals between the exhaust system components.

If you have hinged or casement windows the conventional kit may not work. Instead, you will have to place a large sheet of plexiglass in the opening or cover it with plastic visqueen curtains. The same is also true if you plan to cut the opening through an exterior wall.

Step 3 - Measure and Cut to Size

Whether you are using plastic sheeting, plexiglass, or the window kit, you will need to measure the intended vent opening to trim your material to the appropriate dimensions. You can also cut the exhaust hose shorter but be careful not to make it too short.

If you aren't using a window, you can also take this time to measure, mark, and cut the vent hole with a drywall saw.

Step 4 - Attach Exhaust Hose

Connect the venting adapter to the window kit or plastic and set it in the exhaust opening. Slide the window closed as far as possible to wedge the kit into place or add padding and weather stripping around the plastic to get it snug. Then, fit one end of the exhaust hose into the vent hole and the other to the discharge opening at the back of the portable air conditioner. You can test for airtightness around the hose openings with soapy water; bubbles will form at the site of leaks.

Once everything is properly secured, you will be set to use your portable AC unit whenever you need!