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At 0925, while performing the HPCI time to … At 0925, while performing the HPCI time to rated flow surveillance, operators discovered the HPCI flow controller to be operating sluggishly in the automatic mode. The surveillance was stopped and HPCI was declared inoperable.</br>The licensee entered a 24-hour LCO per Technical Specification 3.5.5.2 due to Torus Cooling being in service on RHR loop "A". The licensee is now in a 14-day LCO as a result of securing Torus Cooling and restoring RHR LPCI loop "A". Troubleshooting was performed with I&C prior to securing HPCI. I&C is pursuing controller restoration to operability.</br>The licensee has notified the NRC Resident Inspector.</br>* * * UPDATE ON 01/15/04 @ 1035 BY DAVID HALLONQUIST TO C GOULD * * * RETRACTION</br>BASIS FOR RETRACTION:</br>NRC Notification 40343 was conservatively made to ensure that the Eight-Hour Non-Emergency reporting requirements of 10CFR50.73 were met pending the evaluation of an atypical condition observed with the High Pressure Coolant Injection (HPCI) Flow Controller while performing scheduled preventative maintenance testing for the HPCI System. After the off-site vendor lab completed testing the circuit board, the HPCI Flow Controller performed sluggishly, and it was determined that the initial NRC Notification was not required.</br>During surveillance testing on 11/20/03, the HPCI System was started and met or exceeded the Technical Specification minimum requirements designed to demonstrate HPCI System Operability. While testing the specific components of the system, the HPCI Flow Controller was observed to be behaving erratically. Although the HPCI System was still capable of performing its required design safety function, the Shift Manager declared the system inoperable with a concern that further degradation of the flow controller "could have" prevented the HPCI System from performing its design safety function.</br>Troubleshooting determined that the amplifier circuit board for the controller was not performing as expected. This board was subsequently replaced with one from stock and tested satisfactorily before declaring HPCI fully operational. The faulty amplifier circuit board was sent to an off-site vendor lab for testing and analysis.</br>The vendor determined that the problem was due a capacitor failure on the board. The capacitor was removed, and the board was re-tested to determine the extent of the effect that this condition would have on the HPCI System performance. This testing revealed the same indications and system response that was initially observed by Vermont Yankee personnel during testing and troubleshooting. Therefore, it has been concluded that with the preventative maintenance system's surveillance as-found condition, the HPCI System was capable of performing its design safety function, and the flow controller's performance would not have degraded any further as a result of this condition.</br>Therefore ENS Event Number 40343, made on 11/20/03, is being retracted.</br>The NRC Resident Inspector was notified.</br>Reg 1 RDO( Holody) was informed.tor was notified.
Reg 1 RDO( Holody) was informed.
14:25:00, 20 November 2003 +
40,343 +
11:19:00, 20 November 2003 +
14:25:00, 20 November 2003 +
At 0925, while performing the HPCI time to … At 0925, while performing the HPCI time to rated flow surveillance, operators discovered the HPCI flow controller to be operating sluggishly in the automatic mode. The surveillance was stopped and HPCI was declared inoperable.</br>The licensee entered a 24-hour LCO per Technical Specification 3.5.5.2 due to Torus Cooling being in service on RHR loop "A". The licensee is now in a 14-day LCO as a result of securing Torus Cooling and restoring RHR LPCI loop "A". Troubleshooting was performed with I&C prior to securing HPCI. I&C is pursuing controller restoration to operability.</br>The licensee has notified the NRC Resident Inspector.</br>* * * UPDATE ON 01/15/04 @ 1035 BY DAVID HALLONQUIST TO C GOULD * * * RETRACTION</br>BASIS FOR RETRACTION:</br>NRC Notification 40343 was conservatively made to ensure that the Eight-Hour Non-Emergency reporting requirements of 10CFR50.73 were met pending the evaluation of an atypical condition observed with the High Pressure Coolant Injection (HPCI) Flow Controller while performing scheduled preventative maintenance testing for the HPCI System. After the off-site vendor lab completed testing the circuit board, the HPCI Flow Controller performed sluggishly, and it was determined that the initial NRC Notification was not required.</br>During surveillance testing on 11/20/03, the HPCI System was started and met or exceeded the Technical Specification minimum requirements designed to demonstrate HPCI System Operability. While testing the specific components of the system, the HPCI Flow Controller was observed to be behaving erratically. Although the HPCI System was still capable of performing its required design safety function, the Shift Manager declared the system inoperable with a concern that further degradation of the flow controller "could have" prevented the HPCI System from performing its design safety function.</br>Troubleshooting determined that the amplifier circuit board for the controller was not performing as expected. This board was subsequently replaced with one from stock and tested satisfactorily before declaring HPCI fully operational. The faulty amplifier circuit board was sent to an off-site vendor lab for testing and analysis.</br>The vendor determined that the problem was due a capacitor failure on the board. The capacitor was removed, and the board was re-tested to determine the extent of the effect that this condition would have on the HPCI System performance. This testing revealed the same indications and system response that was initially observed by Vermont Yankee personnel during testing and troubleshooting. Therefore, it has been concluded that with the preventative maintenance system's surveillance as-found condition, the HPCI System was capable of performing its design safety function, and the flow controller's performance would not have degraded any further as a result of this condition.</br>Therefore ENS Event Number 40343, made on 11/20/03, is being retracted.</br>The NRC Resident Inspector was notified.</br>Reg 1 RDO( Holody) was informed.tor was notified.
Reg 1 RDO( Holody) was informed.
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00:00:00, 15 January 2004 +
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22:44:00, 24 September 2017 +
11:19:00, 20 November 2003 +
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14:25:00, 20 November 2003 +
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