The Symphony has the largest water tank we tested, which doesn’t translate into more power – it just means it lasts longer (two days and nights, in this case). But as it happens, the Symphony is powerful, too, with an airflow of 840 cubic metres per hour that allows it to cool rooms up to 12m 2. That’s a bigger space than many air coolers – although still not huge. No air cooler can chill a big living room. For that you will need a proper air conditioner. Surprisingly, its lowest setting wasn’t that energy efficient, but its night mode will come in handy if you’re after versatility. Ion technology also sets it apart – by generating ions, it also freshens the air in your room. The associated HomeWizard app (for iOS or Android) allows you to give it voice commands using Siri or Google Assistant. I will never use those. Some will, but I can’t help feeling it would be cheaper without them.

Suitability - The appliance can be used in kitchens, bedrooms, living rooms, home offices, pet rooms, conservatories, etc. It has a coverage range of up to 80 cubic metres and up to 29 square metres. I measured noise at a maximum of 48.5dB on the minimum setting, up to a more powerful 60.1dB on maximum – both measured from 15cm. Effectively, this means that you will always hear the Princess Smart Heating and Cooling Tower when it is turned on.Testers found its selection of air speeds improved their comfort nicely and it was generally quiet too, although not on its highest setting.

Changes made via the app are replicated on the LCD, and changes made via the remote are displayed in the app. Well, for the most part. Using the remote to switch between Cold and Heat modes didn’t always update the app with the correct settings. This will keep your home environment just right all year round as it also doubles as a heater (read what we thought of its warming capabilities here.) As a fan, testers rated its adjustable oscillation, which goes up to a whopping 350 degrees, meaning it can reach multiple people dotted around the same room.All the fans on our list rotate to some extent, but the models with greater ranges of motion can help improve the comfort of several people at once. For a living room, try the Dyson Purifier Cool Auto React, which rotates just shy of 360 degrees. Weight Note that fans don’t generate cool air (apart from this Princess model, which houses a water tank), so limit their usage to when you’re in the room and can feel the benefits. To get the most comfort from your fan, these GHI-approved tips will help boost its ability to circulate cooler air. How we test fans I put the Princess Smart Heating and Cooling Tower through my standard tests. Starting with the regular fan, I measured air speed at 3.08m/s on maximum setting from 15cm away, falling to 1.31m/s at 1m. That’s not bad, although I have tested more powerful fans.

Additionally, it should be easy to use and maintain, with features like air cleaning filters, automatic shutoff and timers. You’ll also want to make sure it’s energy-efficient. The more powerful units use more energy, although all air coolers are much cheaper to run than air conditioners.” Our runner-up fan is a strong all-rounder. With 12 air speeds, it can provide everything from a gentle breeze to a strong flow. It has a broad range of movement too, oscillating at up to 130 degrees to cover multiple people at once, or adjustable downwards if it’s only catering to you. As a result, our testers found it successfully increased their comfort levels.I measured power consumption at a maximum of 1983kW on Heat mode (in fan-only mode, power consumption topped out at just 28.8W). Given the average cost of electricity in the UK (18.9p per kWh), this means that the Princess Smart Heating and Cooling Tower will cost a maximum of 37.48p per hour to run. Note that next to central heating, all electric heaters are comparatively expensive to run. There’s some confusion, understandably. The popular Dyson cooler, for example, is not actually an air cooler, nor an air conditioner, but a fan. Big names like Mylek and ProBreeze all make air cons, fans and air coolers. So it’s important to know what you’re getting - and why.