With the temperature rising and a mini heatwave ahead, many people will be rummaging through cupboards and blowing the dust off their old fans. But there is a better option. A combined fan and purifier will clean and freshen your air and protect you from hay fever – all while keeping you cool. The difference it makes to home air quality is well worth the investment. Now is a great time to buy, with several air purifying fans discounted until 3 July in the UK Dyson Week sale. Dyson fans are some of the best available. Quite apart from their iconic design, they’re quiet, powerful and don’t featu…