Fixed Air Conditioning vs Portable Units and Fans
Every hot spell sells a lot of portable air conditioners, and most of them end up in a garage by September.
Every hot spell sells a lot of portable air conditioners, and most of them end up in a garage by September. It's worth understanding why: it isn't that portables don't work at all, it's that the compromise they make — venting hot air through a hose in a partly open window — undermines the thing you bought them for.
How each one removes heat
A split system has its condenser outside, so heat is rejected outdoors and only cold air is produced indoors. A portable sits entirely inside and pushes hot air out through a hose, which means it also draws warm outside air back in through the gap around the hose. That parasitic gain is why portables struggle in a bright room on a hot afternoon.
Running cost and noise
A fixed inverter system modulates its output and runs quietly because the compressor is outside. A portable runs its compressor in the room with you, at full output, cycling on and off. On both electricity consumed per unit of cooling and on liveability, the fixed system is the more comfortable machine.
The winter argument
A fixed split system is a heat pump and heats efficiently in winter as well as cooling in summer. That is the part most people overlook when comparing purchase prices: you are buying year-round capability, which changes the comparison substantially for a home office or a room that's hard to heat.
When a portable is the sensible choice
If you're renting, can't fit an external unit, or need occasional cooling in a room you rarely use, a portable is a reasonable compromise — and we'd rather tell you that than sell you an installation you don't need. For a bedroom, home office or open-plan living space you use daily, a fixed system is a different category of product.
Common questions
Do I need planning permission for an outdoor unit?
For most domestic properties an external unit falls under permitted development if siting conditions are met, but listed buildings, conservation areas and flats often differ. We'll flag it at survey; confirming with the local authority is the owner's step.
How disruptive is installing a split system?
For a single indoor unit on an external wall, typically a day. Longer pipe runs to reach an internal room take more time and more making good, and we'll set that out before starting.
Is air conditioning expensive to run?
A correctly sized inverter system is far more economical than most people expect, particularly in heating mode where it delivers several units of heat per unit of electricity.
Is finance available?
Yes, on Worcester Bosch air conditioning installations, subject to status and the terms set out on our finance page.