CONDENSER AIR REMOVAL

Question 1

What is the safety function of the Main Vac Breaker (VA-V-8)?

Answer 1

When OPENED, it allows the hotwell to supply Emergency Feedwater (EFW).

Question 2

What are the power sources for VA-P-1A/B/C?

Answer 2

1C/1J/1C 480V.

Question 3

What are the trip conditions for VA-P-1A/B/C?

Answer 3

Motor overload (amber light console left) and high discharge temperature at 210°F.

Question 4

What is the standby auto-start sequence for VA-P-1 pumps?

Answer 4

A-B-C-A.

Question 5

What is the interlock condition for VA-V-5 suction valves?
A: They are interlocked to OPEN with pump start.

Answer 5

They are interlocked to OPEN with pump start.

Question 6

What are the power sources for VA-P-2A/B/C?

Answer 6

1C/1D/1C TP MCC.

Question 7

What are the trip conditions for VA-P-2A/B/C?

Answer 7

Motor overload, high discharge temperature at 185°F, and low seal water pressure (<5# for 25 seconds).

Question 8

What is the purpose of condensate seal water?

Answer 8

It prevents air intrusion and provides cooling for pumps from friction/compression heat.

Question 9

What is the source of seal water for the main vacuum pumps?

Answer 9

The suction side of booster pumps (CO-P-2s), cooled by Circ Water.

Question 10

What is the sequence for breaking vacuum?

Answer 10

(1) Secure Vac Pumps, (2) OPEN Vac Breakers (VA-V-8/VA-V-4A/B), (3) Secure Gland Steam after vacuum reaches 0#.

Question 11

Why is gland steam secured after vacuum reaches 0# during breaking vacuum?

Answer 11

To prevent drawing cold air across the hot rotor and lab seals, which could cause rotor damage.

Question 12

What action is required if off-gas flow exceeds 190 scfm (A0436)?

Answer 12

Start the 3rd VA-P-1 pump and initiate plant shutdown.