Ctrl Room Ventilation

Question 1

What is the purpose of the Ctrl Rm Ventilation?

Answer 1

• Maintain control room below 120°F during 4 hour coping period of Station Blackout
• Maintain normal temp less than 85°F
• Keep CR pressurized
• Maintain acceptable smoke levels in CR
• Keep temperature in CR less than 97 deg F during accident
• Remove iodine and particulate
• Maintain rad levels during DBA less than 5 Rem
• Isolate CR during toxic gas release

Question 2

How does ESW interface with the CRAC?

Answer 2

• Cooling water for condensers

- Backup supply for cooling coils

Question 3

When is the backup cooling capability lost with respect to ESW to the cooling coils?

Answer 3

• Backup capability lost if ESW > 65°F

Question 4

What are the CR Pressurization Fan starts?

Answer 4

• SI in either Unit (Train Spec)
• CR High Rad (unit specific)
• CRCV Fire (CO2 or Halon actuation)
• Manual

Question 5

What the trips of the CRAC chiller package?

Answer 5

• Load Con**
• High Discharge Pressure
• Low Suction Pressure
• Low Temperature
• Low Oil Pressure
• Overload

Question 6

How do VRV-315/325 fail on a loss of air?

Answer 6

• Fail open with full flow to chillers

(ACRDA are motor operated and fail as is on loss of pwr)**

Question 7

Describe a design function of the Control Room Ventilation System?

Answer 7

• Maintains control room habitable for 30 days post accident while maintaining dose less than 5 rem TEDE to satisfy 10 CFR 50.36

Question 8

If U-1 gets a CRCV Fire signal and All U-1 CR Vent Sys Auto actions occur as expected
THEN
U-1 gets a CR High Rad signal,
Does U-1 CR vent Sys realign?

Answer 8

• No, “First in Wins.” The U-1 CR Vent System stays aligned for the U-1 CRCV Fire signal

Question 9

When will HV-ACR-DA-2A Clean Up Intake Damper

HV-ACR-DA-2A go to part open?

Answer 9

-If HV-ACR-DA-2 isn’t in part open after 45 sec since actuation

Question 10

What is the makeup source to chilled water loops and humidifiers?

Answer 10

Demin water

Question 11

What is the normal position of the control room dampers

Answer 11

• 1/1A (CRAC outside supply): OPEN
• 2/2A (CREV outside supply): CLOSED
• 3 (CREV recirc): OPEN

Question 12

What is the position of the control room dampers for a toxic gas release

Answer 12

• 1/1A (CRAC outside supply): CLOSED
• 2/2A (CREV outside supply): CLOSED
• 3 (CREV recirc): CLOSED

Question 13

What is the position of the control room dampers for a cable vault fire

Answer 13

• 1/1A (CRAC outside supply): CLOSED
• 2/2A (CREV outside supply): PARITALLY OPEN
• 3 (CREV recirc): CLOSED

Question 14

What is the position of the control room dampers for a high rad alarm

Answer 14

• 1/1A (CRAC outside supply): CLOSED
• 2/2A (CREV outside supply): PARTIALLY OPEN
• 3 (CREV recirc): OPEN

Question 15

What is the position of the control room dampers for an SI in either unit

Answer 15

• 1/1A (CRAC outside supply): CLOSED
• 2/2A (CREV outside supply): PARTIALLY OPEN
• 3 (CREV recirc): OPEN

Question 16

For toxic gas, do the dampers align automatically or manually

Answer 16

Manual

Question 17

What are the rad monitor numbers that actuate CREV for each unit

Answer 17

• 7401 (U1)

- 8401 (U2)