Aux Building Ventilation

Question 1

What are the AES Fan Starts?

Answer 1

• SI
• Associated Train ECCS pump start
• CTS pump start

Question 2

When is the AES Fan Charcoal bed I/S?

Answer 2

• Phase B (Either Train)
• Ctrl Stch in “Stop” (specific fan)
• Loss of Control Air (specific fan)
• Loss of power to either AES Fan

Question 3

Where does the AES Fan take its suction from?

Answer 3

• CTS Heat Exchanger
• RHR Heat Exchanger
• Charging Pumps (and Reciprocating)
• SI Pump
• RHR Pump
• CTS Pump
• Fans take suction directly from Vestibule

Question 4

What are the AS/AX trips?

Answer 4

• Load Con

- Thermal Overload

Question 5

What are the AFS Trips?

Answer 5

• Load Con
• SFP High Rad (R-5 and VRS-5006)
• Thermal Overload

Question 6

What are the AFX Trips?

Answer 6

• Load Con
• Charcoal Bed Fire
• Thermal Overload

Question 7

When is the AFX Fan Charcoal bed I/S?

Answer 7

• SFP High Rad (R-5)
• SFP High Airborne Rad (VRS-5006)
• Loss of power to either fan
• Loss of control air

Question 8

When do the CCW supply fans start?

Answer 8

• Load Con (Unit Specific)
• 1 U2 AS fan OOS 1 ACCP running
• 2 U2 AS fans OOS 2 ACCPs running

Question 9

What unit are the CCW supply fans powered from?

Answer 9

• # 1 fan powered from Unit 2

- #2 and #3 fans powered from Unit 1

Question 10

How does the CCW fans maintain temperature when its cold outside?

Answer 10

• Recirc damper allows for warm air to be directed from inside Aux Building during cold weather*

Question 11

What does 3.7.13A (FHAEV System during fuel movement) state?

Answer 11

If Required FHAEV train Inoperable or not in operation
IMMEDIATELY:
- Suspend movement of irradiated fuel assemblies in the Aux Building

Question 12

What will cause 12-RV-306 [Vent Stack] to Auto Trip Closed?

Answer 12

• A loss of BOTH Unit 1 AX Fans will close 12-RRV-306

Question 13

What is the purpose of the Charcoal Filters for the Spray Add Tank Room?

Answer 13

• Removes radioactive iodine and methyl iodide from air

Question 14

Do the Spray Add Tank Room Fans trip on a

charcoal fire?

Answer 14

• No, they do not

Question 15

What is the 3.7.12, ESF Ventilation System Basis?

Answer 15

• The system limits radioactive release to within the 10 CFR 100 limits and to 5 rem TEDE for CR operators during recirc mode of a large break LOCA.

Question 16

Why do we manually place SFP Vent in manual Charcoal when working in SFP?

Answer 16

• We manually place SFP in charcoal filter when working in SFP due to FSAR stating that automatic damper operation on a high rad alarm is too slow.

Question 17

Unit 1 has just entered mode 3 following a maintenance outage to replace a leaky fuel assembly. During work on the East RHR pump, an accidental spill causes radiation levels to increase.

The following radiation channels have alarmed:
ERA-7305 U1 East RHR Pump Room - RED
VRS-1505 Unit Vent Effluent Low Range Noble Gas – RED

Which ONE of the following is true regarding system operations based on these conditions?

A. The Auxiliary Building Supply fans have automatically tripped.

B. The AES Fan Charcoal Filter has automatically aligned.

C. The AES Fan Charcoal Filter must be manually placed in service.

D. The Auxiliary Building Supply fans must be manually tripped.

Answer 17

• C. The AES Fan Charcoal Filter must be manually placed in service.

Question 18

What realign on loss of ctrl air?

Answer 18

• Face dampers and bypass dampers

Question 19

Which Aux building fans trip on a load conservation?

Answer 19

• AS
• AX
• AFS
• AFX

Question 20

Which Aux building fans start on a load conservation

Answer 20

• CCW pump fans

Question 21

Do the AES fans trip on a load conservation

Answer 21

No

Question 22

Where is 1-HV-AS-2 located and from where does it receive power & control

Answer 22

• Located in U1

- Power and control from U2