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What does a dehumidifier do? Experts share what you need to know
There are plenty of health benefits to running a dehumidifier
The best dehumidifiers not only defend against damp and mould in your home, but can help dry laundry loads and improve your abode’s air quality – tick, tick, tick.
They work by drawing excess moisture from the surroundings, which can speed up clothes drying times, oust odours and reduce dust and allergens in the air. A must-have during cold weather when dampness rears its ugly head, dehumidifiers are equally useful during the warmer months, as they help to reduce humidity levels in your home.
Along with the best air fryers, dehumidifiers have become a buzzword when it comes to energy efficiency, too. Their cost-buzzing credentials reportedly save you on your household bills. But are they worth the initial investment?
If you’ve been considering taking the plunge, I spoke to a range of experts about everything you need to know when it comes to dehumidifiers, from their health benefits to how they actually work.
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What does a dehumidifier do?
“A compressor dehumidifier is the most common type of dehumidifier used in the UK and uses similar technology to a refrigerator,” explains Chris Michaels, chair and founder of leading company Meaco. “The dehumidifier draws in air from the room using a fan, and this air passes over a cold coil inside the unit, which cools it down and causes the moisture in the air to condense into water droplets.”
He adds: “This water is collected in the dehumidifier’s tank, and the drier air is gently reheated and released back into the room.”
Dr Rebecca Drummond, associate professor in the Institute of Immunology & Immunotherapy at the University of Birmingham, elaborates, saying: “Dehumidifiers help remove moisture in the air, which can help your home feel less humid. Lots of moisture in the air can feel uncomfortable, but it also helps fungal spores from mould to settle and grow. Dehumidifiers can therefore reduce the risk of mould growing in your home”
Katie Lilywhite, air quality expert at AO, adds: “High humidity levels can make a room feel uncomfortable and sticky. A dehumidifier works by pulling in humid air and extracting moisture from it through a refrigeration process.”
The reduced humidity in your home can make the air feel cooler and more comfortable, even if the temperature remains the same.
What are the benefits of a dehumidifier?
Above all, Michaels says that dehumidifiers “help prevent damp, mould and condensation, while improving indoor air quality”.
But, according to Lilywhite, one of their most underrated uses is speeding up the drying time of your laundry. “In colder months, when pegging your washing outside isn’t an option, this can be a lifesaver,” she continues. “Simply put your dehumidifier in the same room where your laundry is drying, near the drying rack or clothesline.” As dehumidifiers work by extracting moisture from the air in your room, they work to significantly reduce drying times.
Michaels agrees, adding that they “offer a low-cost alternative to dry wet washing indoors instead of electricity-guzzling tumble driers”.
Dehumidifiers are also ideal for allergy sufferers. “Many modern dehumidifiers also come with built-in air purifiers, improving indoor air quality by filtering out allergens like dust and pollen,” Lilywhite says.
What are the dangers of mould?
“We breathe in mould spores all the time, but our immune system is very effective at destroying them,” Dr Drummond explains. “In some people with compromised immune systems, mould can grow in the lung and cause a pneumonia-like infection. If not treated properly, mould infections can spread to other parts of the body and become life-threatening.”
But even people with healthy immune systems can suffer from excessive mould exposure (such as living in a damp home). “Breathing in too many spores can overwhelm the immune system, and the fungus may produce toxins or other molecules that damage our lungs,” Dr Drummond says. “Mould should therefore never be ignored, as it could cause a wide range of health issues.”
What is the best dehumidifier to buy?
Whether your home is suffering from damp and allergens or you’re looking to potentially halve your laundry drying times, our review of the best dehumidifiers informs you on what model to buy.
Duux bora smart 30l dehumidifier
Duux’s bora smart 30l was rated the best dehumidifier in our guide. “It’s a high-performance model that’s as stylish as it is functional. It might be large, but it features a premium, minimalist design, which is ideal if you're after a dehumidifier that won’t ruin your home aesthetic,” our tester said.
With a 30l per day extraction rate and a generous 4l water tank, it’s perfect for larger rooms or open-plan homes. “What really sets it apart is its smart functionality. The Duux app is intuitive, responsive, and packed with helpful features,” they added. “It provides real-time air quality readings and enables you to control everything from fan speed to humidity settings, whether you're on the sofa or away from home.”
What to know
- Extraction amount: 30l (continuous with hose)
- Noise level: 30-36dB
- Laundy mode: Yes
- Tank size: 4l
- Dimensions: 51cm x 32cm x 23.5cm
- Weight: 14.5kg
- Energy consumption: Up to 315W
- Price per hour: Up to 8p
For a breath of fresh air, take a look at the best air purifiers to remove pollen, dust and bacteria