ML20087N833

Final Deficiency Rept Re Failed Large Expansion Valve Control Unit for Water Chiller in Auxiliary Bldg Air Conditioning Sys Mfg by Dunham-Bush.Initially Reported on 820727.Also Reported Per Part 21

ML20087N833
Person / Time
Site:	Bellefonte
Issue date:	03/26/1984
From:	Mills L TENNESSEE VALLEY AUTHORITY
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
REF-PT21-84 NUDOCS 8404050062
Download: ML20087N833 (2)

Text

,

-j

+

. w_.,

TENNESSEE VALLEY AUTHORITY i"00 C$esTnu^t'StEeet Yo" E SI t

March 26, 1984 BLRD-50-438/82-52 U.S.' Nuclear Regulatory Commission

. Region II Attn:~ Mr.' James P. O'Reilly, Regional Administrator 101-Marietta Street, NW Suite 2900:

Atlanta,' Georgia 30303

Dear.Mr. O'Reilly:

.BELLEFONTE NUCLEAR PLANT UNIT 1 - FAILED VALVE CONTROL UNIT -

BLRD-50-438/82 FINAL REPORT The ' subject deficiency was initially reported to NRC-0IE Inspector LR.-V. Crlenjak on July 27,1982-in accordance with 10 CFR 50.55(e) as NCR

'1891.. This was followed by our interim reports dated August 25 and

'0ctober 20, 1982 and January 24, July 27, and Novew.ber 22, 1983 Enclosed is our final' report. We consider 10 ' CFR Part 21 applicable to this

. deficiency.

If you have any questions concerning this matter, please get in touch with

R; H. Shell at FTS 858-2688.

Very truly yours, TENNESSEE VALLEY AUTHORITY

)h. hz6 L. M. Mills, Manager Nuclear Licensing

. Enclosure oc: ' Mr. Richard C. DeYoung, Director (Enclosure)

Office of Inspection and Enforcement

.U.S. -Nuclear Regulatory Commission --

. Washington, D.C.

20555

.~ Records Center (Enclosure)

. Institute of Nuclear. Power Operations 1100 circle 75 Parkway, Suite 1500

' Atlanta, Georgia 30339 d.

M 05o062 e40326..'

ADOCK 050 OFFICIAL COW s

9 1983-TVA SOTH ANNIVERSARY.

l

- An Equal Opportunity Employer

I-ENCLOSURE' w

1,4c e

- BELLEFONTE NUCLEAR PLANT UNIT 1 FAILED VALVE CONTROL UNIT NCR 1891 BLRD-50-438/82-52 10 CPR 50.55(e)

FINAL REPORT IDescription of Deficiency The(large expansicn valve control unit, supplied by Air Conditioning,

i..'

Refrigeration and Combustion, Incorporated ( ARC) of Knoxville, Tennessee, 1and manufactured by Dunham-Bush, for the water chiller (1VE-MCHL-172-B) in This item regulates the Auxiliary Building' Air Conditioning System failed.

the refrigerant to the chiller which provides cooling for safety-related O

, equipment.

The. control unit' is an electronic relay melosed in a " black box." It is not serviceable nor. can any maintenance be performed on it.. This problem has

~

occurred in other Dunham-Bush chillers at Bellefonte (BLN) and is considem generic only to,BLN.

JSafety Implications i

i i d uncorrected, failure of the control unit

.Hadithe' subject condit on rena ne -

-in the Auxiliary Building air-conditioning system could have resulted, t

This could have

- reducing the cooling capability of the subject chiller.

resulted ' in ~ overheating ' of. ' safety-related equipment which could adversely

' affect. the safe operation of the plant..

Corrective Action i

t tive

. An identical control unit was installed by the vendor serv ce represen a 13, 1983, and requested on April 4, - 1983. nTVA contacted - the vendor on JuneThe vendor stated in their letter the causo:of -failum be analyzed.

f the control units from

. November 3; j1983,Tthat they have tested several o

.BLN and-determined that the most common mode of failure is an open. How discontinuity filter capacitor.

cause of the failums. The vendor also stated that they have not received d

. any deficiency reports by other customers, and that Dunham-Bush has fcun l-an alternate - supplier for the relay.

The control unit " failures experienced to date have occurred during the first' The control

, few-minutes in the'startop testing of the chiller in operation..

~

(units on two ~of.the diillers were subsequently changed out and the chillers I

We-have experienced no further failums after the placed.--in service.

chillers became' operational and, because of this, we believe the failure

rate

of.the control unit is greatly. reduced after equipment is placed in operatione We ~ are purchasing new control units for all the chillers as g

Espares and these will be stored in the " controlled" warehouse until needed.

Operability of the All _ nit 1 chillers have been started and are in use.

unit:2 chillers will' be demonstrated during startup' testing of these units

~

u I

at a future time'in the construction phase..

U g

i t.

,.?

~

m

.