Portable air conditioner setup

A portable air conditioner is usually bought in the middle of a heatwave, when there is no time for a split system or no permission from the building. It is called portable, but to actually cool a room the hot air has to go outside through a tight seal. Otherwise the room gets back the heat the unit has just pulled out of it.

What setting up a portable air conditioner involves

The key part is the exhaust hose. The handyman picks the method that suits your window and building:

• a zip-up fabric window seal fixed to the sash and frame of a tilt-and-turn window;
• a panel in a part-open window or balcony door with a hole for the hose;
• a vent through the glass or the wall with a grille, if the unit stays for good: that needs the owner’s or building’s consent.

On top of that: placing the unit near the window, cutting the hose to a sensible length, checking how condensate is handled, and a first run to test the cooling.

Mistakes that stop it cooling

Most often the hose is too long with several bends, or simply poked through a gap in the window with no seal. Hot air comes straight back in and the unit runs flat out for nothing. The second mistake is too little power for the room: a portable unit copes with a bedroom but may struggle with a large south-facing living room. The handyman will tell you on site.

What to prepare

• the unit unpacked, with the hose and window kit if one came with it;
• space by the window and a socket within reach of the cable, without an extension lead;
• a close-up photo of the window in the job, so it is clear which kit will fit.

Common questions