ML20084D787
| ML20084D787 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 12/10/1970 |
| From: | Hoyt H COMMONWEALTH EDISON CO. |
| To: | Morris P US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 8304120343 | |
| Download: ML20084D787 (1) | |
Text
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DCC 'Ar December 10, 1970 t i. a 5 DEC 141970 > r;s ykt SCTK4 p / ww.n g s Division of Reactor Licensing /,6 / g[ Dr. Peter A. Morris, Director I# blI U. S. Atomic Energy Commission C f?a shing t on, D.C. 20545 SUBJ ECT: LICENSE DPR 19, D'tESDEN NUCLEAR PO'!ER STATION UNIT #2, SECTION 6.6 C OF THE TECHNTCAL S?ECIFICATIONS
Dear Dr. Morris:
This is to report a coaditioa relating to Main Steam Isolation Valve "1 A" Pilot Valve which had an indicated temperature in excess of 150oF for four days. Probl em, Investigation and Corrective Action The problem was discovered on November 10, 1970. "1A" MSIV pilot temperature indicated 1520F. A subsequent exercise of the valves as required by 4.7.D.5 of the Technical Specifications proved them to be operable. The temperature remained at approximately this value with daily surveillance tests until November 13. Drywell ventilation system ad,ustments were made on November 14 to 18 which reduced the pilot valve temperatures significantly. Also, on November 23 the amplifier sensitivity of the Bristol recorder uhich monitors the MSIV temperatures was increased. This' minor ad.justment lowered the recorded temperatures by four to five degrees. 'N It was therefore concluded that the recorder was indicating ; temperatures approvimately five degrees high and that the actual pilot ' valve temperature was not above the limitation imposed by the Technical Specifications. C <=-9 / II. K. Hoyt \\ Superintendent HKH:dmc 8304120343 701210 d PDR ADOCK 05000237 ~ -; C 1 ui S PDR s- \\ 4 '$ W /}}