How is a boiler feed pump typically sized?

A boiler feed pump is typically sized to ensure that it can meet the demand for water needed by the boiler system effectively. The correct sizing requirement is that the pump must supply at least 100% of the water required for normal operating conditions. This capacity accounts for the total water needed to replenish the boiler as it produces steam while compensating for losses such as steam leaks or condensation return.

While there may be scenarios where a higher percentage could be considered, such as factoring in future expansions or additional loads, the sizing of 200% is generally excessive and could lead to inefficiencies in operation and unnecessary costs. Therefore, sizing at 100% ensures reliability, efficiency, and operational safety within the system.

In practice, factors like operational head, temperature pressures, and system dynamics would typically be considered to ensure that the pump can adequately meet the needs without being oversized, which can lead to mechanical issues and increased energy consumption.