Impact of nozzle material and integration practices on defrost efficiency and system compliance in heat pump fans
The performance of heat pump systems is closely tied to the efficiency of their fan units - both operation and defrost cycles, which significantly affect seasonal performance factors. This contribution investigates the influence of different nozzle materials on defrost speed and overall energy requirement. A comparative analysis between metal and polymer-based nozzles reveals the differences and consideration regarding chances and risks in airflow guidance, weight, manufacturing costs, and thermal behavior. Special attention is given to the nozzle’s role during defrosting, where optimized designs can reduce cycle duration and energy consumption. A second focus addresses the growing responsibility of heat pump manufacturers in ensuring proper fan integration. Driven by the requirements of the Ecodesign Directive (ErP), system manufacturers will become accountable for the aerodynamic and acoustic performance of the fan assembly. This shift necessitates a deeper understanding of the interactions between nozzle, grille and fan, as well as their impact on system efficiency and regulatory compliance. The paper presents practical insights into selecting suitable nozzle technologies and highlights how targeted material choices and design strategies can enhance both defrost performance and economic viability. Furthermore, it discusses how regulatory developments are transforming traditional supplier relationships. These findings aim to support more informed design decisions in the development of next-generation heat pump units.