The experimental study focused on spiral finned tube heat exchangers utilising phase change materials (PCM) for efficient heat storage. The research shows how the thickness of the fins can significantly influence heat transfer rates and shows the advantages of using twisted fins over traditional straight fins, which can enhance PCM storage rates. To understand the system’s performance, a detailed parametric analysis is conducted, examining how variations in flow rates and temperatures affect the charging time of the PCM. The study aims to identify the energy storage capacity of spiral finned tube configurations and the performance of the fin in real-world applications. This study examines the performance of heat exchangers across different operating conditions, focusing heat transfer fluid (HTF) flow rate such as 20 LPM, 24 LPM and 28 LPM, as well as inlet temperatures such as 65 °C and 75 °C. According to the results, the PCM’s melting time decreased from 120 min to 90 min when the input temperature was changed from 65 °C to 75 °C, indicating a 25% increase in charging efficiency. Additionally, an increase in HTF flow rate from 20 LPM to 24 LPM resulted in a 15% decrease in melting time. The findings show the potential of spiral-finned tube heat exchangers in improving thermal energy management, making them suitable for various applications.