Save $270 on a refurbished three-in-one Dyson air purifier, humidifier, and fan at Amazon September 26, 2023 landred The Dyson Pure Humidify + Cool is on sale at Amazon for $379.99, a saving of 42% compared to the refurbished price at Dyson of $649.99. It’s a humidifier, HEPA air purifier, and a fan, all-in-one.