40AO-9ZZ20 Loss of HVAC

Question 1

During 40AO-9ZZ20 Loss of HVAC, what are the major mitigating steps for Loss of Normal Chillers

Answer 1

• Attempt to restart Chillers
• Maintain WC < 50°F
• If unable to maintain < 50° CLOSE WCN-70 Radwaste and Control bldg isolation

Question 2

During a loss of CEDMCS room cooling, what temperature would require a shutdown and why?

Answer 2

• > 104°F

- SCR breakdown may cause slipped/ dropped CEA

Question 3

If cooling is lost to CEDMCS room, what actions are required?

Answer 3

• Limit CEA motion to only ASI control
• establish temporary ventillation
• Shutdown if > 104°F

Question 4

What may occur if CEDMCS cabinet fans are lost?

What actions are taken to mitigate?

Answer 4

• Spurious CEA malfunctions
• Limit CEA motion to ASI control
• CEDMCS not in AS
• Open cabinet doors
• Temporary ventillation

Question 5

When will CEDM coil damage occur if CTMT CEDM cooling is lost?

Answer 5

• RCS ≥ 300°F

- 40 minutes

Question 6

If CNTMT CEDM cooling is lost how long do you have to restore cooling?
What is required if cooling cannot be restored?

Answer 6

• Restore in 10 minutes OR start rapid shutdown
• Secure S/D if restored in 40 minutes
• Trip Rx before 40 minutes
• Cooldown to < 300 in 4 hours

Question 7

During a loss of cooling to AF pump rooms:
When is temporary ventilation required?
What is the analyzed temperature?
What is the qualified temperature?

Answer 7

• 101°F temporary ventilation
• < 104°F analyzed**
• 150°F AFA qualified
• 156°F AFB qualified

Question 8

During a loss of CH pump room cooler, How long can CH pumps run without cooling?
when would you consider stopping a CH pump?

Answer 8

• 100 hours

- > 120°F

Question 9

If Control Building HVAC is lost, when would you de-energize BOP-ESFAS and why?

Answer 9

• > 119°F in MCR
• simultaneous failure of BOTH load sequencers
• Causes continuous load shed

Question 10

If Control Building HVAC is lost, when would you be required to down power PMS?

Answer 10

• > 80°F in computer room

Question 11

What is the CR air temperature limit?

Answer 11

• 80°F

- Restore in 30 days

Question 12

What is the concern with a loss of ESF Equipment Room Essential HVAC?

Answer 12

• 1 Fan cools 2 inverters
• LCO 3.8.7 entry and restore in 1 hour

(LCO may be exited with temporary ventilation)

Question 13

What is the most limiting analyzed acceptable temperature limit for DC equipment, battery rooms and class
switchgear?

Answer 13

• 120°F

- 30 days

Question 14

What is the electrical penetration room temperature limit?

Answer 14

• 101°F

- LCO entry and temporary ventilation required

Question 15

What is the most limiting analyzed acceptable temperature limit for electrical pen rooms?

Answer 15

• 122°F

- 30 days

Question 16

During a loss of Main Generator Collector housing cooling, what is the temperature limit for collector brushes?

Answer 16

• 100°C

Question 17

What is required if temporary blowers are used for venitilation?

Answer 17

• 4 hour temperature monitoring