Question 246Steam Plants - 1st Asst/Chief

The correct answer is A) manually by throttling the auxiliary feed stop-check valve. When operating with the auxiliary feed line, the feed water flow is controlled manually by throttling the auxiliary feed stop-check valve. This allows the operator to manually adjust the water flow as needed, rather than relying on automatic controls. The other options are incorrect because the main feed water regulator (B) controls the primary feed line, not the auxiliary line, the auxiliary feed water regulator (C) adjusts the spring setting rather than directly controlling flow, and the economizer bypass (D) is not involved in controlling auxiliary feed water flow.