Yes, you have to descale your kettle regularly. Minerals present in tap water will cause scale to build up inside your kettle when water is heated.
Regular descaling prolongs the life of the kettle. We recommend that you descale regularly - at least monthly and keep the inside of the kettle clean. This will help extend the life of the kettle.
You must only use a descaler that is suitable for use in plastic products. If you use a descaling agent, follow the instructions on the bottle or package to descale your kettle.