What may be required after replacing APU components?

After replacing APU components, a secondary startup, often referred to as "burping" the system, may be necessary to ensure that the new components are correctly integrated and functioning with existing systems. This process helps to purge any air that may have entered the fuel lines during replacement, ensuring optimal fuel flow and system pressure. It also allows for checks on the system performance and confirms that no error codes or malfunctions are present following the component replacement.

While a full system reset and routine maintenance checks are important in various contexts, they are not specifically required immediately after replacing APU components. Additionally, the idea that no further actions are required is not accurate, as conducting a secondary startup is crucial to validate the operation of the newly installed components.