A large part of the Dutch naval history is exhibited in the Dutch Naval Museum. This is not the whole collection; the largest part of this collection is stored in a depot. The depot of the Dutch Naval Museum is an advanced building with an advanced HVAC installation. The building consists of a box in a box construction. The inner concrete boxes of this construction are used for storing the artefacts. This box is surrounded by a cavity zone. The indoor air of the cavity zone is only treated with local heating. The indoor air of the concrete storage boxes is treated with a high reliability HVAC plant. The artefacts that are stored require tight demands of indoor climate. Abruptly changes of this indoor climate can be harmful for the artefacts. In this research answers will be tried to find of what will happen with the indoor climate when a major failure in de air handling unit occurs. There will also be researched if it is recommended to treat the air of the cavity zone in case of a mayor failure. The Dutch Naval Depot gives housing to one of Dutch most valuable collections of artefacts, there cannot be experimented with the indoor climate of the depot self. The key in answering these questions lies in simulation. In this research the components of the air handling unit are modelled. The models will be verified with design conditions and validated with data from the buildingmanagementsystem. Subsequently the components of the air handling unit are combined and coupled to the buildingmodel. The buildingmodel is validated with on-site measurements. Eventually the complete model is fitted with control strategy. This strategy is also analogue to the buildingmanagementsystem. To simulate failure in the HVAC installation a faultgenerator is build and coupled to the air handling unit components. The complete model can eventually simulate the indoorclimate of depotzone and cavityzone. The complete model is used to simulate the indoorclimate when a fault in the HVAC installation occurs. The results of these simulations will be analyzed when faults occur in the 'normal' situation (HVAC treats depotzone) and in the 'altered' situation (HVAC treats air in cavityzone). This complete model is used for the first time. The accuracy and reliability of the model is not yet estimated. Therefore only preliminary conclusions can be made. The preliminary conclusions of these results when the HVAC installation works as it should, when the fault is detected and the HVAC installation switches to 100% recirculation of air are; That there no significant changes of indoorclimate can be estimated. But when this safety measure (100% recirculation) does not work, the results show that this will affect the indoorclimate negatively. When this happens the 'altered' situation is recommended. If the indoorclimate of the cavity zone is treated, the role of quarantinespace should not be underestimated. In this case disturbance of indoorclimate are not handled by the HVAC plant. The conclusions extracted in the progress of this research are; the data from the buildingmanagmentsystem is less useful are then expected and side effects of HVAC components that are often neglected have more influence. This is caused by overcapacity of the HVAC installation.