[RWC is Right Wing Console.]
[Hotel refers to the non-engineering loads for passenger spaces etc.]
NOTE: IF the instrument air is required during the repair period, open valve NI-8V to connect in the ship's service air system. Cross connect only if no likelihood exists that the ship's service air system will also be exhausted. The reactor is not to be operated with the two systems cross connected.
The loss of instrument air will disable all of the pneumatic indicators and controllers, leaving only the electrical indicators and interlocks operable. All of the diaphragm operated valves which fail closed on loss of air, will close shutting off flow throughout the plant in the lines where these valves are located. There are a few exceptions to this; the following valves fail open on loss of air: CW-29V, CW-39V, CW-129V, PP-29V, PP-34V, NI-5V, NI-7V and the main feed pump automatic speed control valve.
After the reactor is scrammed the buffer charge pumps must be shut down immediately. The make-up valve, bypass valve, and the buffer seal return valve all fail closed. When the bypass valve closes, the standby charge pumps comes on the line at half speed; this action does not open the valve. This all occurs in less than one minute. The only flow path for the seal water is to the primary system through the seals into the reactor and can cause the charge pump relief valves to open. Therefore, until the charge pumps are stopped, the pressurizer level will be rising because the letdown control valves fail closed.
The operator will be unable to determine how the plant is operating, therefore, his only alternative is to scram the reactor and prepare to remove the decay heat from the reactor.
The decay heat can be removed from the core by the emergency cooling system.