How does a portable air conditioner work?
It's a self-contained box on wheels. CHOICE explains that it draws in warm, humid room air, cools and dries it, and blows it back out. The heat it removes goes out through a hose to a window, and most come with a window kit to seal the gap around the hose.
The moisture it pulls from the air collects in a tank you empty, or drains away through a tube.
Why portables struggle
CHOICE calls single-hose portables quite inefficient, and explains why. Pushing hot air out through the hose lowers the air pressure in the room, so warm air is drawn back in from the rest of the house to replace it.
The ACT Government puts it plainly: a portable makes you feel cool while you sit in front of it, but often leaves the house warmer overall.
CHOICE also says single-hose units generally carry no energy stars, and that portables are noisier inside than most split systems, measuring 57 to 74 dB on a high setting.
Portable or split, side by side
| Portable | Split system | |
|---|---|---|
| Setting it up | Plug it in and run the hose to a window | Indoor and outdoor units fitted by a licensed installer |
| Efficiency | Single-hose units are quite inefficient, CHOICE says | The ACT guide gives a CoP of 3.7 average, 6.4 excellent |
| Energy label | Single-hose units generally have no stars | Blue cooling and red heating stars, by climate zone |
| Noise in the room | 57 to 74 dB on high, per CHOICE | Most are quieter inside than a portable, CHOICE says |
| Water | A tank to empty, or a drain tube | A drain line to the outside |
| Moving house | Comes with you | Stays with the house |
When a portable is the right call
Rinnai says portables suit renters, temporary cooling, or spot-cooling a room where a fixed system isn't an option. That's fair. If you can't put holes in the walls, or you only need relief through a heatwave, a portable is a reasonable buy.
You don't need an installer to start one up. NSW's licensing rules for air conditioning work exclude self-contained single-phase plug-in units, and give portable home air conditioners as the example.
Victorian renters should know a portable doesn't count toward the rental minimum standards. Consumer Affairs Victoria says the main living area must have a fixed heater, not a portable one, and the cooling rules that start on 1 March 2027 call for fixed, non-portable units too. Our rental rules guide has the detail.
If you're buying a portable, check
- Cooling capacity in kW to suit the room (see the sizing question below).
- That the window kit suits your windows, whether they slide, swing or tilt.
- The noise figure on high, if it'll run in a bedroom.
- How it handles water: a tank you empty, or a tube to a drain.
- The warranty. Midea lists 2 years on its portables against 7 on its splits, and Rinnai's 7 year warranty extension leaves portables out.
What you can do yourself
You can
- Set it up as the manual says, and seal the window gap with the kit.
- Close the door to the room so the cooled air stays put.
- Empty the water tank regularly, or set up the drain tube.
- Clean the filter as the manual describes.
Leave to a licensed installer
- Fitting a split system, which needs an ARC-licensed technician.
- Any new power circuit for a split.
- Repairs inside the sealed refrigerant circuit, on either kind.
- Sizing a split from the room's heat load.
What we'd do
Where we'd land
Renting, or only need help through a few heatwaves? A portable sized for the room is a sensible buy, as long as you seal the window and close the door. If you own the place and summers are long, we'd skip the portable and have a split specialist fit a small split in the room you use most. It's quieter, it's more efficient, and it heats in winter too.
