Operational challenges in large-scale ammonia heat pump systems

José Joaquín Aguilera*, Wiebke Meesenburg, Torben Ommen, Jonas Lundsted Poulsen, Kenneth Rugholm Kramer, Wiebke Brix Markussen, Benjamin Zühlsdorf*, Brian Elmegaard

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review


The implementation of large-scale heat pumps in district heating systems is expected to play an important role in future integrated energy systems. District heating systems with large-scale heat pumps can benefit from using renewable energy sources and recovered excess heat. Improving the operation of heat pump systems may lead to cost and energy savings and increase the possibilities for providing ancillary services.

This study presents an overview of operational challenges that occur in large-scale ammonia heat pump systems based on information provided by their owners and operators. A survey was conducted, where twenty-five Danish and Norwegian district heating and industrial companies were asked about the characteristics of the heat pumps they operate and for a description of faults and operational challenges that they have experienced.

Moreover, their current monitoring and control possibilities were inquired including the possibility of providing frequency regulation services to the power grid using the existing heat-pump systems. Three companies that manufacture and provide maintenance services to ammonia heat pump systems were also asked about common faults that occur in such systems as well as strategies they use for fault detection and prevention.

The results of the study highlight the potential for improvement in current strategies to monitor and control heat pump systems. Most of the critical faults described by operators were identified in the compressor, evaporator as well as source heat exchangers and intake filters. Faults that led to a shutdown of the system like compressor breakdown were often identified after the incident occurred.

Further, the predictive maintenance for recurring faults, such as frosting of air-source evaporators or fouling has been found to have an improvement potential.

Original languageEnglish
Title of host publicationProceedings of the 34th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems 2021
Publication date2021
ISBN (Print)978-171384398-6
Publication statusPublished - 2021
Event34th International Conference on Efficency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems - Taormina, Sicily, Italy
Duration: 28 Jun 20212 Jul 2021
Conference number: 34


Conference34th International Conference on Efficency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems
CityTaormina, Sicily
Internet address


  • ammonia
  • Control
  • Fault detection and diagnosis
  • Flexible operation
  • Large-scale heat pump
  • Monitoring


Dive into the research topics of 'Operational challenges in large-scale ammonia heat pump systems'. Together they form a unique fingerprint.

Cite this