Comparative analysis of building energy simulation using manufacturer-verified performance data: Focusing on variable refrigerant flow (VRF) heat pump system

Precise modeling of cooling and heating systems is essential for building energy simulation, particularly for designing high-energy efficiency buildings and achieving low-carbon targets. This study evaluates how performance input conditions affect the accuracy of building energy simulation with a variable refrigerant flow (VRF) heat pump system in EnergyPlus. A validated testbed model, calibrated with field measurements from the test facility in South Korea, was used to compare three case configurations: (Case 1) default EnergyPlus VRF curves, (Case 2) default curves with manufacturer-rated coefficient of performance (COP), and (Case 3) manufacturer-derived curves with the rated COP. Results indicate that simulations using manufacturer-based curves and COP achieved the closest alignment with measured data, while default inputs produced the largest deviations. In whole-building simulations, Case 1 shows substantial error, with CV(RMSE) of 59 %, and Case 2 reduces error, with CV(RMSE) of 13 %. Case 3 presents the most accurate results, presenting CV(RMSE) of 9 %. Simulation using manufacturer-derived curves and rated COP could capture the system’s real-world temperature- and load- sensitive behaviors more effectively. The novelty of this study lies in developing and validating a manufacturer-informed curve-fitting and simulation approach that quantitatively improves EnergyPlus VRF model, including a quantified error reduction from 59 % to 9 %. These findings demonstrate the critical role of precise real-world performance data in enhancing simulation accuracy and present a practical framework for improving reliability in building energy assessments and performance-oriented HVAC system design. • Performed comparative study of VRF system reflecting manufacturer-derived curves. • Validated EnergyPlus VRF system simulation model with real-world measurements. • Reduced CV(RMSE) from 59 % to 9 % using updated COP and manufacturer-based curves. • Highlighted the importance of real-data-based curves for VRF simulation reliability.