Feedwater Heating Flashcards
(9 cards)
What happens on a rise of 4th Pt heater?
- LV4 modulates open
- LV24 modulates open
- Hi alarm
- LV24 full open
- LV5 closes
- LV75s close
- hi-hi alarm
- Trips HDL pump
- MOV22 & NRV23 from 9th stage ESS close
What happens to the LP heater string on a Hi-Hi lvl of the 1st or 2nd pt heater?
The string will isolate (MOV32 & 33 close)
What happens when the hi-hi condition clears on the 1st and/or 2nd pt heater?
The isolation valves will stop where they are when the condition clears.
What is the purpose of the min flow for the 4th pt heater?
Keeps the pump cool
What is the purpose of the LV2 in the FWH sys?
Control level in the 2nd pt drain tank
What happens as 5th pt heater level increases?
- LV5 opens
- LV25 opens
- Hi alarm
- LV25 full open
- LV6 closes
- Hi-Hi alarm
- MOV28 closes
What position does LV6 fail in the FWH system?
Fail Closed
What happens as 6th pt heater level increases?
- LV6 modulates open
- LV26 modulates open
- Hi alarm
- LV26 full open
- LV65 close
- Hi-Hi alarm
- MOV3 & AOV81 close
What is the Rule of Thumb as hi level alarm come in on FW heaters?
On Hi Lvl: water sources isolate
On Hi-Hi Lvl: steam sources isolate
