W DOC AIRBUS | AMM A320F

Check Nitrogen Charge Pressure on Hydraulic Power Accumulators

TASK 29-10-00-200-008-A
Check Nitrogen Charge Pressure on Hydraulic Power Accumulators

ZONE: 100
ZONE: 196
ZONE: 744
FIN: 1070GM
FIN: 2070GM
FIN: 3070GM
1. Reason for the Job
Refer to the MPD TASK: 291000-14
CHECK NITROGEN CHARGE PRESSURE ON HYDRAULIC POWER ACCUMULATORS
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
SAFETY CLIP - CIRCUIT BREAKER
No specific
AR
WARNING NOTICE(S)
 B. Consumable Materials
REFERENCE
DESIGNATION
(Material No.14CCB6)
Testing Medium-Leak Detection - Oxygen System
 C. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
100
LOWER HALF FUSELAGE INCLUDING RADOME
196
HYDRAULIC COMPT AND FAIRINGS
744
MAIN DOOR
195BB, 196BB
 D. Referenced Information
REFERENCE
DESIGNATION
TASK 12-14-29-614-001-A
Fill the Hydraulic Power Accumulators with Nitrogen
TASK 29-00-00-864-001-A
Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 29-00-00-870-003-A
Bleeding Procedure of the Green Hydraulic System Downstream of the Engine Pump
TASK 29-00-00-870-007-A
Bleeding Procedure of the Yellow Hydraulic System Downstream of the Engine Pump
TASK 29-00-00-870-009-A
Bleeding Procedure of the Blue Hydraulic System Downstream of the Blue E-Pump
TASK 29-11-14-000-001-A
Removal of the HP Manifold of the Green Hydraulic System
TASK 29-11-14-400-001-A
Installation of the HP Manifold of the Green Hydraulic System
TASK 29-11-21-000-001-A
Removal of the Accumulator-Air Pressure Gage
TASK 29-11-21-400-001-A
Installation of the Accumulator-Air Pressure Gage
TASK 29-11-22-000-001-A
Removal of the Accumulator-Gas Charging Valve
TASK 29-11-22-400-001-A
Installation of the Accumulator-Gas Charging Valve
TASK 29-11-42-000-001-A
Removal of the Green Power Accumulator
TASK 29-11-42-400-001-A
Installation of the Green Power Accumulator
TASK 29-12-14-000-001-A
Removal of the HP Manifold of the Blue Hydraulic System
TASK 29-12-14-400-001-A
Installation of the HP Manifold of the Blue Hydraulic System
TASK 29-12-21-000-001-A
Removal of the Accumulator-Air Pressure Gage
TASK 29-12-21-400-001-A
Installation of the Accumulator-Air Pressure Gage
TASK 29-12-22-000-001-A
Removal of the Accumulator-Gas Charging Valve
TASK 29-12-22-400-001-A
Installation of the Accumulator-Gas Charging Valve
TASK 29-12-42-000-001-A
Removal of the Blue Power Accumulator
TASK 29-12-42-400-001-A
Installation of the Blue Power Accumulator
TASK 29-13-14-000-001-A
Removal of the HP Manifold of the Yellow Hydraulic System
TASK 29-13-14-400-001-A
Installation of the HP Manifold of the Yellow Hydraulic System
TASK 29-13-21-000-001-A
Removal of the Accumulator-Air Pressure Gage
TASK 29-13-21-400-001-A
Installation of the Accumulator-Air Pressure Gage
TASK 29-13-22-000-001-A
Removal of the Accumulator-Gas Charging Valve
TASK 29-13-22-400-001-A
Installation of the Accumulator-Gas Charging Valve
TASK 29-13-42-000-001-A
Removal of the Yellow Power Accumulator
TASK 29-13-42-400-001-A
Installation of the Yellow Power Accumulator
TASK 32-12-00-010-001-A
Open the Main Gear Doors for Access
TASK 32-12-00-410-001-A
Close the Main Gear Doors after Access
F Hydraulic Power Accumulator Charge Pressure - Report Sheet
F Pressure Value
3. Job Set-up
Subtask 29-10-00-860-070-A
A. Aircraft Maintenance Configuration
   (1) Make sure that the hydraulic systems are depressurized and put them in the maintenance configuration
(Ref. AMM TASK 29-00-00-864-001).
   (2) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Green, Blue and Yellow hydraulic systems:
-in the flight compartment on the hydraulic section of the overhead panel 40VU
-on the ground service panels of the Green, Blue and Yellow hydraulic systems.
Subtask 29-10-00-865-070-A
B. 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 29-10-00-010-068-A
C. Get Access
   (1) Open the access panels 195BB and 196BB.
   (2) Open one main door of the main landing gear (Ref. AMM TASK 32-12-00-010-001).
NOTE: You can open the left or the right MLG door, but access is better from the left side.
4. Procedure
Subtask 29-10-00-210-057-A
A. Do a Check of the Nitrogen Charge Pressure of the Green, Blue and Yellow System Accumulators
NOTE: When you read the gages, we recommend you to record the temperature and the pressure in the hydraulic power-accumulator charge pressure - report sheet. You must use this report sheet when you make the decision to get AIRBUS support.
F Hydraulic Power Accumulator Charge Pressure - Report Sheet
   (1) Refer to the nitrogen pressure gages on each of the system accumulators (1070GM), (2070GM) and (3070GM) and make sure that the precharge pressure is as follows:
F Pressure Value

deg.C deg.F "P" bar "P" psi
----------------------------------------------------------
-20 - 4 108 1570
-10 + 14 112 1620
0 + 32 118 1710
+10 + 50 124 1800
+20 + 68 130 1890
+30 + 86 136 1970
+40 +104 142 2060
+50 +122 147 2130
+60 +140 153 2220

NOTE: A wait time of one hour makes the measurement more accurate because of the temperature compensation of the accumulator.
   (2) If the accumulator pressure is in the given limits, between "P" and "P" minus 15 bar (217.5566 psi), no more steps are necessary.
   (3) If the accumulator pressure is more than the correct pressure "P":
     (a) Adjust the accumulator pressure as necessary (Ref. AMM TASK 12-14-29-614-001).
   (4) If the accumulator pressure is "P" minus more than 15 bar (217.5566 psi), do the steps that follow:
     (a) Adjust the accumulator pressure to the correct nominal value "P" (Ref. AMM TASK 12-14-29-614-001).
     (b) After 20 minutes, do a check of the accumulator pressure:
       1 If the accumulator pressure has the correct value "P", plus/minus 7 bar (101.5264 psi):
  • No more steps are necessary.
       2 If the accumulator pressure is "P" plus more than 7 bar (101.5264 psi):
  • Reduce the accumulator pressure to the correct value "P".
       3 If the accumulator pressure is "P" minus more than 7 bar (101.5264 psi):
         a Do a leak check with the oxygen leak detector Testing Medium-Leak Detection - Oxygen System (Material No.14CCB6) on the gas manifold of the accumulator.
         b If it is possible to stop the leaks, pressurize the accumulator (Ref. AMM TASK 12-14-29-614-001).
         c If it is not possible to stop the leaks, replace the accumulator, gage, charging valve or manifold as necessary:
         d If there are no external leaks, replace the accumulator and do the applicable bleeding procedure:
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 29-10-00-410-068-A
A. Close Access
   (1) Make sure that the work area is clean and clear of tools and other items.
   (2) Close the access panels 195BB and 196BB.
   (3) Close the applicable main door of the MLG (Ref. AMM TASK 32-12-00-410-001).
   (4) Remove the WARNING NOTICE(S).
Subtask 29-10-00-865-069-A
B. 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
[Rev.10 from 2021] 2026.04.01 00:14:13 UTC
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