Containment HVAC Flashcards
What is purpose of Containment Building Normal ACU ?
Used to maintain temp & humidity inside containment to support equipment operability
What’re the the Containment Normal ACUs cooled by ?
They’re cooled by Normal Chilled Water
How’re the Containment Building Normal ACU paired together ?
A & B are paired
C & D the other pair
What is the normal running arrangement for the Containment Building Normal ACU ?
A & C running
OR
B & D running
Where does Containment Building Normal ACU draw air from ? Where is it discharged to ?
Draws air from containment & discharges back into containment after being cooled
When are the Containment Building Normal ACU heaters automatically energized ? When do heaters automatically turn off ?
-They’re energized when temperature is to low
-Turns off when there is low air flow
Where are Containment Building Normal ACU operated from ?
Operated from Control Room
What happens if one of the Normal ACU fans trip ? What is the time delay
After 60 seconds the other ACU fan will start
What will trip all operating containment Building Normal ACU ?
SIAS will trip all Normal ACUs
What happens to Containment Normal ACUs on LOP ? When power is restored how long will it take for Normal ACUs to restart
-ACUs will be loadshed and when power is restored BOP ESFAS Load Sequencer ACU will start after 5 seconds
Where are Containment Building Normal ACU powered from?
Powered from CLASS 480VAC LoadCenter(PG)
When are Pre-Access Normal AFU operating ?
-Operating for personnel access to containment building DURING power & PRIOR to opening Containment for an outage
What’re the Containment Building Normal subsystem(Pre-Access Normal AFU) used for ?
-Controls airborne radioactivity in containment required for personnel access, WITHOUT adding makeup air
Where are the Pre-Access Normal AFU operated from ?
Control Room
Where is the Pre-Access Normal AFU powered from ?
480VAC LoadCenter (NG)
What does the CEDM Cooling subsystem do ?
Provides cooling to CEDM area on top of Reactor Vessel Head for equipment operability
How many CEDM Normal ACUs ? How many Fans in each ACU ?
-Two ACUSs
-Two Fans PER ACU
What water is used to cool the CEDM ACUs?
Nuclear Cooling Water for Cooling Coils
How many CEDM Normal ACUs are normally running ?
-One ACU normally operating with BOTH fans running
-Other ACU is in standby
Where do the CEDM Normal ACU draw air from ? Describe flow path from where the air is drawn from ?
-Draws air from bottom of Reactor Vessel Head around CEDMS
-Air is cooled before it’s discharged to upper containment atmosphere
Why is it permissible to be able to have one CEDM ACU Fan running ?
Operation is permitted because calculations indicate single fan provides adequate cooling for CEDMS
Why’re Backdraft dampers installed at discharge of CEDM Normal ACU Fan ? What happens if “Short Cycling” is happening?
-Used to prevent revere flow through a secured ACU fan which allows “Short Cycling”
-“Short Cycling” reduced CEDM Cooling
If both fans for CEDM Normal ACU trip what will happen ?
-Low DP across ACU will be sensed, which will auto start other ACU after 120 seconds
What signal will trip ALL the CEDM Normal ACUs?
SIAS will trip all
What happens to CEDM Normal ACUs on a LOP ? What happens when power is restored ?
-CEDM ACUs will load shed
-BOP ESFAS will start them back up after 55 seconds
Where are CEDM Normal ACUs powered from ?
Powered from PG
What do the Reactor Cavity cooling system provide cooling for ?
-Cools Reactor Cavity & Primary shield to maintain concrete temp
How many Reactor Cavity Cooling fans are there ? Which ones are normally running ?
-There are 4 fans “A,B,C,D”
-One fan from each pair are normally running (A,C & B,D)
When will the standby Reactor Cavity Cooling fans be energized ?
They’re energized manually if Reactor Cavity temp reaches allowable max
Where do the Reactor Cavity fans draws air from ?
Air is drawn from Containment and discharged into Reactor Cavity area
When a ‘Reactor Cavity fan’ trips, how is it sensed and how long will it take to turn the stand by fan on?
-Sensed low D/P across fan
-other fan in that pair will auto start after 60 seconds delay
What is the Pressurizer Cooling subsystem used for ?
Ventilates PZR space within PZR Missile Shield to support equipment operability
How many PZR Cooling fans are normally operating?
Only one in operation & other fan in standby
Where do the PZR Cooling Fans draw air from?
-Draws air from TOP of PZR Compartment and exhaust to atmosphere
-When air is drawn from top, there is also air drawn from bottom which cools the PZR Compartment
What will trip the PZR Cooling Fans ? What happens when one PZR Cooling Fan trips ?
-Low D/P is sensed
-Other fan will start after 60 second delay
What signal will trip a PZR Normal Cooling fan ?
SIAS
Where are the PZR Normal Cooling Fans Powered from ?
SIAS LoadShed MCC
What is the Tendon Gallery Ventilation system used for ?
Supper equipment operability and provide habitable environment
What does Tendon Gallery Ventilation consist of ?
-Supply Fan
-Exhaust Fan
Where are the Tendon Gallery Fans powered from ?
480VAC MCC
Where does the MSSS Ventilation supply fan, supply air to?
-MSSS Building rooms at & above 100’
-Main Steam Containment Penetrations
-Main Feedwater Containment penetrations
How many MSSS Ventilation Supply & Exhaust fans are normally running ?
-Operated LOCALLY
-One 100% capacity supply running
-Two 100% exhaust fans for main steam and Feedwater penetrations
Where are the Main Steam & Main Feedwater Supply/Exhaust Fans operated from?
-Operated by local handswitch inside panel next to fans
What trips a MSSS Supply Fan ? What happens when it trips ?
-Sensed Low D/P will trip fan
-Other fan starts in 60 seconds
Where are MSSS Supply/ Exhaust fans powered from ?
Powered from 480VAC MCC (NH)
What building is RU-1 Monitoring? Where does it draw its sample from & where does it discharge too?
-Containment Building Atmosphere
-Draws from containment & discharges back to containment
What will close the Containment Isolation Valves for the RU-1 suction/return line ?
CIAS will close the Containment Isolation Valves
What is the Tech Spec for Containment Air Temperature ?
It should be less than 117F
