Heat Pump Technology Filter Clean Alarm Smart Check Heat Pump Technology 9 kg Drying Capacity (kg) A++ Energy Efficiency Class 50 kg Net Weight Heat Pump Technology and A++. While the Wrinkle Free program limits the creasing in your clothes to make ironing easier, Quick Dry gives you fast results when you need them. In addition to the A++ Energy Efficiency, the Sensor Dry function uses moisture sensors to turn off the machine when clothes are dry, so you consume less energy and save on your electricity bills. Helpful reminder for filter cleaning The Filter Clean Alarm provides a helpful reminder when its time to clean the condenser filter, as it's easy to forget. And a sensor also checks that the condenser really has been cleaned.