With summers getting hotter, more and more people are looking to invest in air conditioning – especially now, in winter, when demand is lower and prices have come down.
We know they help to reduce the temperatures in our homes, but can they be of any use during the colder seasons for tackling damp, condensation and mould, and could they be a good replacement for the best dehumidifiers?
To find out whether they're up to both jobs, we asked air quality experts for their thoughts – including which is most cost-effective.
Can air conditioning units reduce humidity in the home?
We've got good news for air conditioning owners – your unit can be used to reduce the humidity levels in your home, so you may not need to spend more money on buying a separate appliance.
We know what you're thinking – the last thing you want in winter is to be blasted with ice-cold air, but Laura Bradbury, Head of Ecommerce at VonHaus, says some air con units have a special setting that can reduce how cool it feels.
“Some air conditioning units also have a separate dehumidifier or ‘drying’ mode," she explains. "This is designed specifically to remove excess moisture rather than cool the room, allowing you to use the unit for moisture control even when you don’t need the cooling setting."
So how does it work? When humid air passes over the cold evaporator coils, it causes water vapour to condense into liquid droplets, which are then drained away via a hose or collected in a tank (depending on which model you have).
This three-in-one unit will cool, heat and dehumidify your home, and features app control, a timer function and a quiet mode.
Laura Bradbury is Head of eCommerce at online homeware and garden retailer Vonhaus, and is responsible for developing and growing the brand.
Is an air conditioning unit or a dehumidifier more effective?
While your air conditioning unit can be used to dehumidify a room, Martyn Fowler, founder of Elite Renewables, says he would still recommend a dehumidifier for that purpose.
"The benefit of air conditioning is that you can cool the house in the summer and if you have a reverse-cycle system you can use it for heating in winter too," he says. "But using the cooling function to remove moisture during the colder months isn't very practical. You're cooling a room that you're probably already paying to heat."
Not only that, but a dehumidifier is obviously a much smaller investment – especially if you don't think you'll use your air con unit that much for cooling anyway.
As always, Martyn says it's crucial to get to the bottom of your damp problem. Whether you're buying a dehumidifier or an air conditioning system, it's only going to treat the symptoms, as opposed to tackling the cause of excess moisture in your home.
After testing this budget-friendly dehumidifier, I was impressed with its easy setup, portable design, and ability to double as an air purifier.
Founder of Elite Renewables, Martyn Fowler is one of the UK's leading renewable technology experts, working with heat pumps for the last 2 decades. His passion for decarbonisation matched with a deep technical experience of the technology make him one of the industry's go-to experts for all things renewable.
Are dehumidifiers more cost-effective than air conditioning units for reducing humidity?
If your main goal is to reduce condensation and lower the humidity levels in your home, then a dehumidifier is the most practical and economical option, according to Laura Bradbury.
She says that, in most cases, it will cost less to run per hour compared to a portable air conditioning unit, but the exact figure will depend on the model, the setting you use, your electricity tariff and how long it's been running for.
"The running cost always depends on how hard the system has to work. If it's 30°C outside and you're trying to cool the house to 21°C, that's a different job from heating the same house to 21°C when it's 5°C outside," Martyn adds. "Efficiency generally drops as the outdoor temperature gets colder and the system needs to defrost the outdoor coil."
How long should you run an air conditioning unit to reduce humidity?
Just like dehumidifier running times, "there's no set number of hours because it depends on how humid the room is and the type of air conditioning unit you've got," says Martyn Fowler. "I'd run it for an hour or two and check the humidity."
He recommends aiming for a relative humidity of around 40 to 60%, which you can monitor by placing hygrometers (like these ones from Amazon) around your home. These display the humidity levels as well as the temperature.
To conclude, if you've already got one of the best portable air conditioners, it's well worth checking if it can be used on a 'drying' setting before going out to spend money on a dehumidifier. However, if we had to choose between the two to reduce excess moisture, the dehumidifier wins on effectiveness and cost-efficiency.
Found this helpful? You may want to learn the difference between wall-mounted vs portable air conditioners or find out whether a cooling fan can reduce condensation.
