The Thy 40-28G bypass valve (BPV) opens and fuel bypasses the receiving separators when which differential pressure is sensed?

The Thy 40-28G bypass valve (BPV) is designed to monitor the differential pressure across the receiving separator to maintain optimal fuel flow and system efficiency. When the system senses a differential pressure of 15 pounds per square inch (psi) across the receiving separator, the bypass valve triggers to open. This action allows fuel to bypass the receiving separator, preventing overpressure situations that could lead to system malfunctions or inefficiencies.

In this context, sensing a pressure differential at the receiving separator is crucial because it ensures the separator operates within its designed parameters. If the pressure difference exceeds this threshold, it indicates that the separator may be encountering issues such as blockages or high flow resistance. Therefore, the bypass valve's opening at 15 psi ensures the system can continue to operate effectively by redirecting flow away from a system component that may be under duress.

This response highlights the critical nature of monitoring pressure differentials in maintaining the overall reliability and functionality of the fuel system, emphasizing the importance of the correct operating parameters.