If the available system inlet pressure, also termed static pressure, falls below 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 level, e.g. from a roof 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 lesser Pump NPSHrequired).