Connecting an Exhaust Hose to a Portable Air Conditioner

Every portable air conditioner needs an exhaust pipe to enable it to vent the hot air which it is removing from the room. Most units come with an exhaust hose which is designed to lead from the portable air conditioner to the window.

Portable air conditioner units need to vent hot air; if the machine is not able to vent this air, they can break or run inefficiently. Running a portable air conditioner without using an exhaust hose will cause the area behind the unit to get very hot – so instead of cooling, the room, you may end up increasing the heat.

Attaching the Hose

In your exhaust hose kit, you should have the connecting parts for an exhaust hose (including attachments and sealers) and a window filter kit, which allow the user to vent air properly. The hose should be at least five feet in length, and is usually around 5 inches across. The filter kits are essentially foam, which is designed to attach to the window and prevent hot air from outside coming in to the room; the exhaust hose fits through a small hole cut into the foam. This filter will fit most window and door frames, although they do not always suit casement windows.

  1. Place the portable air conditioner near to the window you wish to use as a venting outlet.
  2. Slide the exhaust hose connecting parts over the discharge vent, which is located at the back of the air conditioner.
  3. Add the exhaust hose to the connecting part.
  4. Set up the window filter kit so that the window is adapted to the exhaust hose; fit the foam to the window.
  5. Connect the exhaust hose to the window filter kit.
  6. Start the air conditioning unit, and check that all connecting parts are fitted tightly.

Take care not to extend the exhaust hose, as this can cause backpressure, making the portable air conditioner heat up. The hose should be as straight as possible while the air conditioner is working.


It is not necessary to attach the exhaust hose to a window in order to vent; the kits will attach to most sliding doors, or with a little bit of customizing, the exhaust can be fitted to vent out of a wall, or a low ceiling. How much modifications you desire to make will depend upon whether you are planning to buy a portable air conditioner, or simply rent it for a short time period. Buying allows you cheap and regular access to a portable air conditioner, even in the hottest of weathers, whereas renting allows you to test the unit to see how you feel about it.

Exhaust pipes will also not be needed in areas where hot temperatures are acceptable at the rear of the portable air conditioner unit, for example in stock rooms or if the AC unit is being used to cool computers in an IT department.