A Study on the Short-Cycling Behavior of Jockey Pumps in High-Rise Fire Protection Systems Using Pressure Reducing Valves

The jockey pump system plays a critical role in maintaining consistent pressure and a fully charged state in fire protection systems during normal operation. However, frequent start-stop cycles, known as intermittent operation or chattering, commonly occur because of pressure fluctuations within the piping network. Although previous studies have attempted to resolve this issue by adding pressure- reducing valves, the problem remains unresolved. This study aims to address the root cause of intermittent operations through structural system design, rather than relying solely on component-level solutions. Experimental investigations were conducted using the pipe diameter, pressure differential, and flow rate as key variables. Based on the results, the behavior of the intermittent operation caused by the application of pressure-reducing valves was analyzed along with the proposed structural improvements. The findings aim to enhance the reliability and safety of fire protection systems in high-rise buildings.