Analyzing technical challenges from large-scale heat pumps in operation

To understand which specific requirements from the industry can be fulfilled by digital twins solutions, a survey was carried out among manufacturers, maintenance providers and operators. The results of the survey are now available.

Analyzing common practices and challenges related to heat pump and refrigeration systems is among the first research activities performed in the project. Therefore, a survey study was carried out in the early stages of the project where manufacturers, maintenance providers and operators were asked about technical challenges related to the operation of large-scale heat pumps using ammonia as refrigerant. The results of the study were summarized in a research publication presented at the 34th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems (ECOS).

The study included thirty-four heat pump systems from Danish and Norwegian district heating and industrial companies. The companies provided information about the heat pumps they operate and a description of observed faults (or malfunctions in the system) as well as operational challenges that they have experienced. In addition, three companies that manufacture and/or maintain large-scale heat pumps were asked about common faults that they have identified and strategies to detect and mitigate such faults. All the information shared in this study was treated confidentially, where the companies, people and systems involved were anonymized.

As a result from the study, it was possible to identify that most of the critical faults described by operators occurred in the compressor and in the source side of the heat pump, such as in the heat exchangers. Catastrophic faults associated to a shutdown of the system were commonly identified after the incident happened.Moreover, it was identified that predictive maintenance related to recurring faults, such as frosting or fouling of heat exchangers, could be improved.

The information obtained from this study will be highly beneficial for the development of digital twin solutions about monitoring, fault detection and diagnosis as well as operation optimization. The upcoming steps in this project will focalize on the development of advanced frameworks for performance monitoring and fault detection and diagnosis, considering the outcome from this survey study.

For further information about the study, please contact José Joaquín Aguilera Prado, PhD student at the Technical University of Denmark (  


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