Every heatwave, the shops sell out of portable air conditioners. They have their place, but many people who buy one end up disappointed. Here's an honest comparison with a fitted split system, including when a portable unit really is the better choice.
How each one works
A portable air conditioner contains everything in one box on the floor. It pushes hot air out through a wide hose, which has to go through a window or door.
A fitted split system puts the noisy parts, the compressor and main fan, in an outdoor unit. A slim indoor unit sits high on the wall, and the two are connected by small refrigerant pipes through a single hole in the wall.
Side by side
| Portable | Fitted split system | |
|---|---|---|
| Cooling | Struggles in larger or sunny rooms, and many single-hose units pull warm air in from elsewhere | Sized to the room and holds a steady temperature |
| Noise indoors | Compressor is in the room, and many are loud enough to disturb sleep | Quieter indoors; manufacturers rate many at around 19 to 22 dB(A) on low |
| Efficiency | Generally lower, varies by model | Generally higher with inverter technology, varies by model |
| Heating | Usually none, or basic | Efficient heat pump heating |
| Security | Window or door left partly open for the hose | Windows closed and locked |
| Space | Takes up floor space, with a hose across the room | Wall-mounted, nothing on the floor |
| Installation | None, just plug it in | Must be installed by an appropriately F-Gas-certified business |
| Upfront cost | Low | Higher |
When a portable unit makes sense
- You rent and can't make changes to the building.
- You only need occasional cooling for a few days a year.
- It's a stopgap while you plan a proper installation.
When fitted is worth it
- You want to sleep properly through a heatwave. Quiet matters most in a bedroom.
- You work from home, or from a garden office, and need a steady temperature all day.
- You'd like efficient heating in spring and autumn as well.
- You plan to stay in the home for a few years. The efficiency and comfort are felt every summer.
Next step
If you're weighing up a fitted system, our costs guide explains what goes into the price and how to estimate running costs. When you're ready, send us an enquiry and we'll pass it to an independent local installer, who can contact you about a survey and quotation.