Households using dehumidifiers to combat condensation and mould are being urged to follow a simple 20cm rule to avoid common mistakes that reduce effectiveness. Consumer champion Which? has highlighted five errors that can hinder performance and even pose safety risks.
The advice, shared on TikTok by @whichuk, stresses that dehumidifiers should never be placed directly against walls or furniture. Most models require at least 20cm of clearance to allow proper air circulation. The device should also be kept away from heat sources and vents, which can impair its function.
Running a dehumidifier with windows or external doors open is another mistake, as it will struggle to combat incoming humid air. Which? also warns against letting wet clothes drip onto the unit, calling it a potential fire hazard. Instead, the dehumidifier should be positioned so its airflow is directed towards the laundry.
Filter maintenance is crucial: manufacturers recommend cleaning it every two to four weeks, either with a gentle vacuum or by washing if heavily clogged. For desiccant dehumidifiers, users should never turn them off at the mains; instead, use the control panel to allow the fan to cool down internal components.
Ideal Home echoed the advice, with Duux brand manager Chloe King stating that for optimal efficiency, the dehumidifier should be placed at least 20cm from every wall and away from drafts. Following these guidelines can help prevent damp and mould, which the Centre for Sustainable Energy identifies as the most common cause of household damp.
