Iso Condenser Flashcards
Why must IC be isolated if tube leak?
prevent untreated radiation release
Why is only one IC Makeup pump run at a time?
Prevents cavitation due to common suction line
What happens to RPV level on IC initiation?
Level will rise 4-5inches
Why is Contaminated Demin Water not desirable as IC make-up?
Causes possibility of uncontrolled release of radioactive materials to environment.
Why must ADS vlvs be closed if RPV level cannot be mantained above -50”?
to prevent ADS inititation
What indications are present on an IC tube leak?
Rise in vent rad levels
Rise in shell side temp
Rise in shell side level coincient w/ rising temp
Drop in Rx Level
Why must 4399-74 vlv be opened before IC Makeup pump started?
minimizes water hammer
What are signs of IC Condensate Return Line Low?
extended time to condense steam to fill return piping.
excessive heating of shell side water (to point of steaming)
Temp lower in tube bundle as covered by condensate
May require makeup
How long must 2-1301-3 valve be held in “CLOSE” position after close indication? Why?
5 seconds to ensure full closure due to location of limit switches
What is the preferred order of RPV Pressure control?
IC with makeup from clean demin from IC makeup
IC with makeup from clean demin using clean demin pumps
HPCI in pressure control mode
IC with Fire water makeup via 2(3)-4102 (if Fire Water suppression NOT REQUIRED)
ADS System relief valves (w/ RPV level above -50)
IC w/ contaminated makeup
Why is IA used for IC operation?
1301-17 and 20 valves
Why must RBX floor drain Sump A be available to put IC in stanby?
Shell side drains there
Why must CST level be >90,000 prior to putting IC in standby?
To ensure that HPCI has adequate suction. Condensate transfer takes suction below standpipe
Why would shell side level rise with tube leak?
steam from leak enters shell side and heats it up. Density of water decreases and expands, causing level to go up. Also, steam leaving primary side will condense adding inventory
Why would tube side temp rise indiacte 1301-3 valve leakby?
tube side is normally a stagnant water column.
Leakby creates a pathway for flow travel allowing hot water/steam to travel through the system
