Heater Drains

Question 1

What are the heater drain pump trips?

Answer 1

LO LO level in the heater drain tank

Suction valve closed

Lo Flow - “A” (1.0 mlbm/hr)
“B (.8 mlbm/hr)
45 second time delay

MPD

BUV

(FTCKTS______)

Question 2

Where are the low pressure feedwater heaters located?

Answer 2

In the main condenser

Question 3

What will isolate a LPFWH string?

Answer 3

Hi and HI HI level in the feed water heater

Question 4

What isolates when LPFWH isolates?

Answer 4

Condensate side

Question 5

What are the power supplies to the Heater Drain Pumps?

Answer 5

A - 13

B - 14

Question 6

When are HDP put in service?

Answer 6

> 40%

Question 7

How much flow comes from the heater drain pumps? (percentage of total flow)

Answer 7

30% from heater drain pumps

70% from condensate system

Question 8

What will low water level in the heaters cause?

Answer 8

Flashing (Erosion)

Question 9

What will high level in the heaters cause?

Answer 9

Backing up (dump valves open)

Question 10

What’s the purpose of the heater drains?

Answer 10

Provide continuous removal of non-condensable gas from steam (shell) side of the feed water heaters. Allows water to be returned to feedwater system

Question 11

What’s the purpose of the MSR drains?

Answer 11

Collect water from feedwater system to increase:

• efficiency
• operating stability
• reliability

Question 12

Where do the LPFWHs drain to?

Answer 12

1 drains to condenser
4 drains to 3
3 drains to 2
2 drains to condenser

Question 13

Where do the HPFWHs drain to?

Answer 13

5 drains to HDT

6 drains to HDT

Question 14

Where does the 1st stage reheater drain tank drain to?

Answer 14

HDT

Question 15

Where does the 2nd stage reheater drain tank drain to?

Answer 15

2nd stage drains to #6 HPFWH, which drains to HDT

Question 16

When does the HPFWHs dump control logic reset to a lower level?

Answer 16

< 45% CTP

Question 17

When does the HPFWHs dump control logic reset to normal level?

Answer 17

> 48% CTP or < 6% CTP

Question 18

What auto closes level control valve for #5 HPFWH?

Answer 18

Hi-Hi level in 5A and 5B OR

HI-Hi level in HDT AND 5A or 5B

Question 19

When will #6 HPFWH isolate and what valves does it close?

Answer 19

Hi-Hi level closes inlet from 2nd stage reheater drain tank

Question 20

What isolates when HPFWH isolates?

Answer 20

Supply steam

Question 21

What level in moisture separator drain tank will trip main turbine?

Answer 21

Hi-Hi level in the MSR separator drain tank

Question 22

Where do dump valves drain to?

Answer 22

Main condenser

Question 23

Where do drain valves drain to?

Answer 23

their associated drain tank location

Question 24

Where do relief valves drain to?

Answer 24

Main condenser

Question 25

What 2 tanks will trip the main turbine if it reaches a Hi-Hi level?

Answer 25

Moisture separator drain tank

Moisture separator shell drain tank

Question 26

When does LPFWH dump valve control reset to a lower level?

Answer 26

< 38% CTP

Question 27

When does LPFWH dump valves control reset to normal logic?

Answer 27

> 42.5% CTP

Question 28

Where does the CTP calculation come from for the dump valve logic?

Answer 28

APRM channel 4 and total flow

Question 29

What must be running for level control valve to work automatically?

Answer 29

Heater Drain Pumps

Question 30

When will heater drain tank level control valves open with at least one pump running AND discharge valve open?

Answer 30

> 0%, 520A starts to open

50% 520A is full open

100% F520 A/B full open

If level continues to rise, 518 A-E will open sequentially with “E” opening first

Question 31

How is level controlled in the heater drain tank with no pumps running?

Answer 31

F520 A/B are interlocked closed

F518 A-E open to maintain level. E opens first