It may only be the start of July, but the UK has already seen several record-breaking warm days. Our heat-retaining homes have quickly become uncomfortable, and those long, sweaty commutes certainly haven't helped. With forecasters predicting more hot weather in the weeks ahead, it's worth knowing how to keep your home as cool as possible.
It’s no surprise that sales have been rocketing for essential items like portable air conditioners, fans and air coolers. Hot weather may be becoming more common, but air conditioning is still far from a household staple in the UK. We all know switching it on cools the room, but what’s really going on inside the unit? To get the low down on how these pieces of kit work, I spoke to Tom Houlker, air conditioning installation and service expert and director at Houlkair.
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How does a portable air conditioner work?
An air conditioner doesn’t actually make cold air, explains Houlker. Instead, it moves the heat from inside a room to outside. He explains that warm air from the room is drawn over a cold evaporator coil, where the refrigerant absorbs the heat. The system then transfers that heat outside via the compressor and condenser. In other words, an air conditioner cools a room by removing heat, not by creating cold air.
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How energy efficient are air conditioners?
The efficiency of an air conditioner really depends on usage. It comes down to “how many British thermal units of cooling you get for each kilowatt hour of electricity you pay for,” Houlker explains. “Energy labels are the best starting point, since they show efficiency class and energy use.”
He also advises checking SEER or EER ratings where available. However, he stresses that real-world performance also depends on correct sizing, a sealed exhaust hose and clean filters.
How to make the most of your air conditioner
Houlker recommends keeping usage simple but consistent. He says to “keep the filter clean, seal the window kit properly, shut blinds in direct sun, close doors to unused rooms and do not set the unit colder than you need.”
He adds that lower temperatures don’t cool rooms faster; they just make the system run longer, and that steady airflow and humidity removal are actually what improves comfort.
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How does an air conditioner move air around the room?
"The indoor fan creates the circulation loop. It pulls warm air into the unit and pushes cooled and dehumidified air back across the room. It keeps mixing the air so you do not end up with one cold corner and one hot corner,” Houlkar explains.
“The system works best when you keep the supply air path clear and avoid placing the unit where furniture, curtains or a bed blocks the airflow."
The portable air conditioners to buy
If you’re looking for respite from the heat, home appliance expert Joanne Lewsley has reviewed the best portable air conditioners, however demand is high, so most are now out of stock. But we did find one model in stock from one of our trusted brands, the Dreo smart 3-in-1 portable air conditioner (£599.99, Amazon.co.uk).
Meet the expert
- Tom Houlker: Air conditioning installation and service expert and the director of Houlkair
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