If the available system inlet pressure, also termed static pressure, falls bellow the required pump inlet pressure, suitable measures must be taken to achieve at least an equilibrium such as:
- Increasing the available static pressure at the pump location (positioning the pump at a lower altitude, i.e. from a roof top plant room into the basement to benefit from the increased static head from the higher water column. The pump performance remains unchanged).
- Lowering the fluid temperature (reducing the vapour pressure pD).
- Changing the pump characteristics (reducing the driven speed and / or different pump design with a lower pump NPSHr )
Back to Resources