W DOC AIRBUS | AMM A320F

Deactivation of the Yellow Power Accumulator

TASK 29-10-00-040-006-A
Deactivation of the Yellow Power Accumulator

WARNING: MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE IN POSITION ON THE LANDING GEAR. THIS WILL PREVENT UNWANTED MOVEMENT OF THE LANDING GEAR, AND THUS POSSIBLE INJURY TO PERSONS AND DAMAGE TO THE AIRCRAFT AND/OR EQUIPMENT.
FIN: 3070GM
Task Summary
Access Test Specific Tools Mhr E/T Nb Men
YESNONO1.51.51
1. Reason for the Job
MMEL 29-10-04A
HYDRAULIC SYSTEM ACCUMULATOR
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
CAP - BLANKING (ABS0946V12 TYPE)
OR
OR
No specific
AR
CAP - BLANKING (MS21914-12 TYPE)
No specific
1
CONTAINER 5 L (1.32 USGAL)
No specific
AR
SAFETY CLIP - CIRCUIT BREAKER
No specific
1
WARNING NOTICE(S)
No specific
Torque wrench: range to between 9.5 and 8.5 m.daN (70.06 and 62.68 lbf.ft ) T
 B. Consumable Materials
REFERENCE
DESIGNATION
(Material No.02ABA1)
Phosphate Ester Hydraulic Fluid-General Power - -
 C. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
196BB
 D. Referenced Information
REFERENCE
DESIGNATION
TASK 12-12-29-611-001-A
Fill the Hydraulic Fluid Reservoir with a Hand Pump
TASK 29-00-00-864-001-A
Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 29-00-00-870-007-A
Bleeding Procedure of the Yellow Hydraulic System Downstream of the Engine Pump
TASK 29-00-00-910-002-A
Safety Procedures of the Hydraulic System
TASK 29-10-00-863-002-A
Pressurize the Yellow Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-864-002-A
Depressurize the Yellow Hydraulic System
TASK 29-14-00-614-001-A
Depressurization of the Hydraulic Reservoirs
TASK 29-14-00-614-002-A
Pressurization of the Hydraulic Reservoirs through the Ground Connector
TASK 29-14-00-614-002-A-01
Pressurization of the Hydraulic Reservoirs with the Auxiliary Power Unit (APU)
TASK 29-23-00-860-001-A
Disconnection of the Isolation Coupling of the Power Transfer Unit (PTU)
TASK 29-23-00-860-002-A
Connection of the Isolation Coupling of the Power Transfer Unit (PTU)
F Yellow Power Accumulator (3070GM)
3. Job Set-up
Subtask 29-10-00-865-091-A
A. Open, safety and tag this(these) circuit breaker(s):
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
49VUHYD/HYD PWR/B WARN/& CTL2702GJC12
** ON A/C NOT FOR ALL
121VUHYDRAULIC/HYD POWER/Y3803GXN30
** ON A/C NOT FOR ALL
121VUHYDRAULIC/HYD POWER/Y3803GXN31
** ON A/C ALL
123VUB HYD/ELEC PUMP2701GJAB09
123VUY HYD/ELEC/PUMP3802GXAB06
123VUY HYD/ELEC/ELEC PUMP/NORM3801GXAB03
Subtask 29-10-00-860-105-A
B. Aircraft Maintenance Configuration
WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.
   (1) Obey the hydraulic safety procedures (Ref. AMM TASK 29-00-00-910-002).
   (2) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Yellow hydraulic system:
  • in the cockpit on the hydraulic section 40VU of the overhead panel,
  • on the ground service panel of the Yellow hydraulic system.
   (3) Make sure that the Yellow hydraulic system is depressurized and put it in the maintenance configuration.
(Ref. AMM TASK 29-00-00-864-001).
   (4) Depressurize the reservoir of the Yellow hydraulic system (Ref. AMM TASK 29-14-00-614-001).
   (5) Disconnect the isolation coupling of the Power Transfer Unit (PTU) (Ref. AMM TASK 29-23-00-860-001).
   (6) Put a CONTAINER 5 L (1.32 USGAL) below the accumulator to collect the unwanted hydraulic fluid.
Subtask 29-10-00-010-080-A
C. Open the access door 196BB.
4. Procedure
Subtask 29-10-00-614-054-A
A. Release the nitrogen pressure from the power accumulator (3) as follows:
   (1) Remove the end cap (5) from the charging valve.
   (2) Turn the nut (4) to release the nitrogen pressure.
   (3) When the nitrogen pressure is fully released turn the nut (4) to close the charging valve.
   (4) Install the end cap (5) on the charging valve.
Subtask 29-10-00-020-060-A
B. Removal of the Hydraulic Pipe
CAUTION: USE A SECOND WRENCH TO APPLY COUNTERTORQUE TO THE UNION WHEN YOU DISCONNECT/CONNECT HYDRAULIC LINES ON UNIONS. IF YOU DO NOT USE THE SECOND WRENCH, THERE IS A RISK THAT YOU WILL LOOSEN OR TIGHTEN THE UNION TOO MUCH.
   (1) Disconnect the line end fitting (12) from the union (13) of the HP-manifold (14).
   (2) Disconnect the line end fitting (1) from the union (2) of the power accumulator (3).
   (3) Remove the nuts (10), the bolts (7) and the pipe (6) with the clamp-block halves (8) and (9).
   (4) Install the blanking caps on the line end fittings (1) and (12) of the removed pipe (6).
Subtask 29-10-00-420-057-A
C. Installation of the Blanking Caps
CAUTION: USE A SECOND WRENCH TO APPLY COUNTERTORQUE TO THE UNION WHEN YOU DISCONNECT/CONNECT HYDRAULIC LINES ON UNIONS. IF YOU DO NOT USE THE SECOND WRENCH, THERE IS A RISK THAT YOU WILL LOOSEN OR TIGHTEN THE UNION TOO MUCH.
   (1) Apply the Phosphate Ester Hydraulic Fluid-General Power - - (Material No.02ABA1) to the threads of the unions (2) and (13).
   (2) Install the CAP - BLANKING (ABS0946V12 TYPE)CAP - BLANKING (MS21914-12 TYPE) on the unions (2) and (13).
   (3) TORQUE the blanking caps to between 9.5 and 8.5 m.daN (70.06 and 62.68 lbf.ft ) T.
Subtask 29-10-00-865-092-A
D. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
49VUHYD/HYD PWR/B WARN/& CTL2702GJC12
** ON A/C NOT FOR ALL
121VUHYDRAULIC/HYD POWER/Y3803GXN30
** ON A/C NOT FOR ALL
121VUHYDRAULIC/HYD POWER/Y3803GXN31
** ON A/C ALL
123VUB HYD/ELEC PUMP2701GJAB09
123VUY HYD/ELEC/PUMP3802GXAB06
123VUY HYD/ELEC/ELEC PUMP/NORM3801GXAB03
Subtask 29-10-00-790-057-A
E. Leak Test
WARNING: MAKE SURE THAT THE TRAVEL RANGES OF THE FLIGHT CONTROLS SURFACES ARE CLEAR. MOVEMENT OF FLIGHT CONTROLS CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.
   (1) Pressurize the reservoir of the Yellow hydraulic system (Ref. AMM TASK 29-14-00-614-002).
   (2) Pressurize the Yellow hydraulic system (Ref. AMM TASK 29-10-00-863-002).
   (3) After 5 minutes, examine the connections of the blanking cap to the union (13) of the HP-manifold (14). Make sure that there are no hydraulic fluid or nitrogen leaks.
   (4) Depressurize the Yellow hydraulic system (Ref. AMM TASK 29-10-00-864-002).
   (5) Do the bleeding procedure of the Yellow hydraulic system downstream of the engine pump (Ref. AMM TASK 29-00-00-870-007).
NOTE: When you do the bleeding procedure, nitrogen, which has gone into the hydraulic system from the defective accumulator, is removed.
5. Close-up
Subtask 29-10-00-410-080-A
A. Put the aircraft back to the serviceable condition.
   (1) Make sure that the fluid level in the reservoir of the Yellow hydraulic system is correct. Add fluid as necessary (Ref. AMM TASK 12-12-29-611-001).
   (2) Connect the PTU isolation coupling (Ref. AMM TASK 29-23-00-860-002).
   (3) Remove the CONTAINER 5 L (1.32 USGAL) from below the power accumulator.
   (4) Make sure that the work area is clean and clear of tools and other items.
   (5) Close the access door 196BB.
   (6) Remove the WARNING NOTICE(S).
   (7) Make an entry in the logbook.
[Rev.10 from 2021] 2026.04.01 00:14:04 UTC
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