Question 590Steam Plants - Assistant Engineer

The correct answer is D) secure the steam to the main air ejector. When breaking vacuum on a main turbine unit, the first step is to secure the steam to the main air ejector. This is because the main air ejector is responsible for maintaining the vacuum in the condenser. By securing the steam to the air ejector, it stops the removal of air and other non-condensable gases from the condenser, allowing the vacuum to be gradually broken. The other options, such as securing the steam to the gland seal system (A), stopping the main circulating pump (B), or stopping the main condensate pump (C), are not the first step in this process. These actions may be necessary later in the sequence, but securing the main air ejector is the critical first step to begin breaking the vacuum.