The Heating Ventilation and Air Conditioning (HVAC) sector is responsible for a large part of the total worldwide energy consumption, a significant part of which is caused by incorrect operation of controls and maintenance. HVAC systems are becoming increasingly complex, especially due to multi-commodity energy sources, and as a result, the chance of failures in systems and controls will increase. Therefore, systems that diagnose energy performance are of paramount importance. However, despite much research on Fault Detection and Diagnosis (FDD) methods for HVAC systems, they are rarely applied. One major reason is that proposed methods are different from the approaches taken by HVAC designers who employ process and instrumentation diagrams (P&IDs). This led to the following main research question: Which FDD architecture is suitable for HVAC systems in general to support the set up and implementation of FDD methods, including energy performance diagnosis? First, an energy performance FDD architecture based on information embedded in P&IDs was elaborated. The new FDD method, called the 4S3F method, combines systems theory with data analysis. In the 4S3F method, the detection and diagnosis phases are separated. The symptoms and faults are classified into 4 types of symptoms (deviations from balance equations, operating states (OS) and energy performance (EP), and additional information) and 3 types of faults (component, control and model faults). Second, the 4S3F method has been tested in four case studies. In the first case study, the symptom detection part was tested using historical Building Management System (BMS) data for a whole year: the combined heat and power plant of the THUAS (The Hague University of Applied Sciences) building in Delft, including an aquifer thermal energy storage (ATES) system, a heat pump, a gas boiler and hot and cold water hydronic systems. This case study showed that balance, EP and OS symptoms can be extracted from the P&ID and the presence of symptoms detected. In the second case study, a proof of principle of the fault diagnosis part of the 4S3F method was successfully performed on the same HVAC system extracting possible component and control faults from the P&ID. A Bayesian Network diagnostic, which mimics the way of diagnosis by HVAC engineers, was applied to identify the probability of all possible faults by interpreting the symptoms. The diagnostic Bayesian network (DBN) was set up in accordance with the P&ID, i.e., with the same structure. Energy savings from fault corrections were estimated to be up to 25% of the primary energy consumption, while the HVAC system was initially considered to have an excellent performance. In the third case study, a demand-driven ventilation system (DCV) was analysed. The analysis showed that the 4S3F method works also to identify faults on an air ventilation system.
Research suggests that construction clients, as building owner-occupier, are struggling to implement smart maintenance. This thesis assumes that this is due to a failure to fully understand the institutional complexities of smart maintenance. Hence, the aim of this thesis was to improve our understanding of these complexities and to develop theoretical and practical knowledge on the professionalization of construction clients in commissioning smart maintenance through stewardship. Stewardship theory portrays managers and employees as collectivists, pro-organizational and trustworthy, and can be used for designing collaborations based on intrinsic motivation and trust. A first insight from this thesis relates to how institutional complexity in smart maintenance management (SMM) can be understood (study 1). Institutional complexity is defined as the combined effect of 15 interorganizational and intraorganizational tensions that are active simultaneously. A second insight from this thesis relates to the capabilities that construction clients need to address the institutional complexities of SMM and connect various institutional fields (study 2). Using data collected from four cases involving two construction clients, a framework with eight maturity dimensions, involving 23 sub-dimensions, has been developed and validated. The third insight from this thesis relates to the role of the purchasing function in commissioning smart maintenance and emerged from considering the service triad concept (study 3). The findings indicate that the service triad concept fails to provide sufficient detail to adequately describe the construction client’s role in SMM. Hence, the service triad is extended to a service hexad. Our fourth insight relates to intrapreneurial stewardship (study 4). A process model for change implementation through stewardship interventions has been developed and then evaluated in a case study. The process model combines constructs from stewardship theory with intrapreneurship concepts and describes how employees can be coached by leaders during periods of organizational change. Together, the insights from the four studies are synthesized in a framework for client-led innovation in SMM and describe how construction clients can increase SMM maturity in institutionally complex environments through stewardship.
