Annual leakage inspections are mandatory in order to maintain the 6-year leakage guarantee. The recommended retail price for the inspection is approx. 159.00 € and is only accepted by an authorised Dethleffs partner. A certified measuring device is required at the factory for this purpose. The inspection takes between 45 and 90 minutes, depending on the size of the vehicle. The inspection schedule can be found in the user manual for your vehicle.