W DOC AIRBUS | TSM A320F

Decrease and Recovery of Pressure Indication on ECAM

TASK 35-10-00-810-827-A
Decrease and Recovery of Pressure Indication on ECAM

WARNING: KEEP ALL HYDROCARBONS (FUELS, LUBRICANTS, ETC.) AWAY FROM ALL SOURCE OF OXYGEN. OXYGEN BECOMES EXPLOSIVE WHEN IT TOUCHES HYDROCARBONS.
WARNING: CLEAN THE TOOLS AND MAKE SURE YOUR HANDS ARE CLEAN TO PREVENT CONTAMINATION OF THE OXYGEN SYSTEM.
WARNING: IF YOU FIND AN OXYGEN LEAK, RELEASE THE OXYGEN/CREW SUPPLY PUSHBUTTON SWITCH (THE OFF LEGEND COMES ON) TO STOP THE OPERATION OF THE OXYGEN DISTRIBUTION SYSTEM. IF THE LEAK CONTINUES, CLOSE ALL THE MANUAL SHUTOFF VALVES OF THE OXYGEN CYLINDERS. MAKE SURE THAT THERE IS A GOOD FLOW OF AIR IN THE AREA OF THE LEAK. OXYGEN CAN CAUSE EXPLOSIVE FIRES. THERE IS A RISK OF INJURY TO PERSONNEL AND DAMAGE TO EQUIPMENT.
CAUTION: PUT DRY, CLEAN, METAL OR PLASTIC PLUGS ON ALL PIPES OR UNITS REMOVED TEMPORARILY. PUT EACH PIPE OR UNIT IN A SEALED VINYL BAG.
1. Possible Causes
  • CYLINDER-OXYGEN STORAGE [5750HM]
  • XMTR/PRESS REG-OXY [4HT]
  • OXYGEN CYLINDER [5750HM1]
  • OXYGEN CYLINDER [5750HM2]
  • PRESS.TRANSM.REGULATO [4HT2]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 24-41-00-861-002
Energize the Aircraft Electrical Circuits from the External Power
AMM 24-41-00-862-002
De-energize the Aircraft Electrical Circuits Supplied from the External Power
AMM 31-60-00-860-001
EIS Start Procedure
AMM 31-60-00-860-002
EIS Stop Procedure
AMM 35-00-00-860-001
Special Precautions When Working on a Gaseous Oxygen System
AMM 35-11-41-000-001
Removal of the Crew Oxygen-Storage Cylinder
AMM 35-11-41-000-802
Removal of the Crew Oxygen-Storage Cylinders
AMM 35-11-41-400-001
Installation of the Crew Oxygen-Storage Cylinder
AMM 35-11-41-400-802
Installation of the Crew Oxygen-Storage Cylinders
AMM 35-12-41-710-001
Operational Test of the Full Face/Quick Donning Oxygen Masks
AMM 35-13-00-00-
AMM 35-13-15-000-001
Removal of the Oxygen Pressure Regulator/Transmitter
AMM 35-13-15-000-802
Removal of the Oxygen Pressure Regulator/Transmitters
AMM 35-13-15-400-001
Installation of the Oxygen Pressure Regulator/Transmitter
AMM 35-13-15-400-802
Installation of the Oxygen Pressure Regulator/Transmitters
3. Fault Confirmation
Subtask 35-10-00-860-074-A
A. Job Set Up
   (1) Aircraft Maintenance Configuration
     (a) Obey the special precautions when you do work on a gaseous oxygen system AMM 35-00-00-860-001.
     (b) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
     (c) Do the EIS start procedure (Upper ECAM DU and lower ECAM DU only)
AMM 31-60-00-860-001.
Subtask 35-10-00-865-063-A
B. Make sure that this(these) circuit breaker(s) is(are) closed:
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
49VUOXYGEN/CREW/OXY/SPLY1HTHA01
Subtask 35-10-00-700-065-A ** ON A/C NOT FOR ALL
C. Test
   (1) Do the operational test of the full-face/quick-donning oxygen mask AMM 35-12-41-710-001.
Subtask 35-10-00-700-065-B ** ON A/C NOT FOR ALL
C. Test
   (1) Do the operational test of the full-face/quick-donning oxygen mask AMM 35-12-41-710-001.
   (2) On the ECAM control panel, on the DOOR/OXY page, make sure that:
  • A minimum of one of the two oxygen pressure indications decreases more quickly than the normal rate, and
  • The oxygen pressure indication(s) is (are) shown again and is (are) stable after each test.
( AMM 35-13-00-00-)
  • The pressure indication given on the left side of the lower ECAM DU is for the Captain and the Third Occupant. The indication given on the right side of the lower ECAM DU is for the First Officer and the Fourth Occupant.
4. Fault Isolation
Subtask 35-10-00-810-081-A ** ON A/C NOT FOR ALL
A. If during the operational test, on the ECAM control panel:
  • The oxygen pressure value decreases more quickly than the normal rate, and
  • The oxygen pressure value is shown again and is stable after each test.
   (1) Do a check of the valve of the CYLINDER-OXYGEN STORAGE [5750HM] :
     (a) If the cylinder valve is not fully open, open the valve of the oxygen-storage cylinder (5750HM) very slowly and do the test given in Para. 4B.
     (b) If the cylinder valve is fully open:
       1 Replace the XMTR/PRESS REG-OXY [4HT] AMM 35-13-15-000-001 and AMM 35-13-15-400-001.
       2 If the fault continues:
         a Replace the CYLINDER-OXYGEN STORAGE [5750HM] AMM 35-11-41-000-001 and AMM 35-11-41-400-001.
Subtask 35-10-00-700-066-A ** ON A/C NOT FOR ALL
B. Test
   (1) Do the operational test of the full-face/quick-donning oxygen mask AMM 35-12-41-710-001.
Subtask 35-10-00-810-081-B ** ON A/C NOT FOR ALL
C. If the test confirms the fault:
CAUTION: WHEN YOU OPEN THE MANUAL SHUTOFF VALVE ON THE CREW OXYGEN-STORAGE CYLINDER, MAKE SURE THAT:
  • YOU TURN IT VERY SLOWLY
  • YOU TURN IT UNTIL IT IS FULLY OPEN.
IF YOU TURN THE MANUAL SHUTOFF VALVE TOO QUICKLY, YOU CAN CAUSE DAMAGE TO THE EQUIPMENT. IF THE MANUAL SHUTOFF VALVE IS NOT FULLY OPEN, THE OXYGEN PRESSURE DATA CAN BE INCORRECT.
   (1) On the Captain (and Third Occupant) oxygen system only:
  • Do a check of the position of the manual shutoff valve of the OXYGEN CYLINDER [5750HM1] :
     (a) If the manual shutoff valve is not fully open:
       1 Open it very slowly until it is fully open and do the test given in Para. 4B.
     (b) If the manual shutoff valve is fully open:
       1 Replace the XMTR/PRESS REG-OXY [4HT] AMM 35-13-15-000-802 and AMM 35-13-15-400-802.
       2 If the fault continues:
         a Replace the OXYGEN CYLINDER [5750HM1] AMM 35-11-41-000-802 and AMM 35-11-41-400-802.
   (2) On the First Officer (and Fourth Occupant) oxygen system only:
  • Do a check of the position of the manual shutoff valve of the OXYGEN CYLINDER [5750HM2] :
     (a) If the manual shutoff valve is not fully open:
       1 Open it very slowly until it is fully open and do the test given in Para. 4B.
     (b) If the manual shutoff valve is fully open:
       1 Replace the PRESS.TRANSM.REGULATO [4HT2] AMM 35-13-15-000-802 and AMM 35-13-15-400-802.
       2 If the fault continues:
         a Replace the OXYGEN CYLINDER [5750HM2] AMM 35-11-41-000-802 and AMM 35-11-41-400-802.
   (3) On the two oxygen systems:
  • Do a check of the positions of the manual shutoff valves of the OXYGEN CYLINDER [5750HM1] and OXYGEN CYLINDER [5750HM2] :
     (a) If the manual shutoff valves are not fully open:
       1 Open them very slowly until they are fully open and do the test given in Para. 4B.
     (b) If the manual shutoff valves are fully open:
       1 Replace the XMTR/PRESS REG-OXY [4HT] and PRESS.TRANSM.REGULATO [4HT2] AMM 35-13-15-000-802 and AMM 35-13-15-400-802.
       2 If the fault continues:
         a Replace the OXYGEN CYLINDER [5750HM1] and OXYGEN CYLINDER [5750HM2] AMM 35-11-41-000-802 and AMM 35-11-41-400-802.
Subtask 35-10-00-700-066-B ** ON A/C NOT FOR ALL
D. Test
   (1) Do the operational test of the full-face/quick-donning oxygen mask AMM 35-12-41-710-001.
   (2) On the ECAM control panel, on the DOOR/OXY page:
  • Make sure that the two oxygen pressure indications do not decrease more quickly than the normal rate.
5. Close-up
Subtask 35-10-00-860-075-A
A. Put the aircraft back to its initial configuration.
   (1) In the cockpit, on the OXYGEN section of the overhead control and indicating panel 21VU:
  • Release the CREW SUPPLY pushbutton switch (the OFF legend comes on).
   (2) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
AMM 31-60-00-860-002.
   (3) De-energize the aircraft electrical circuits
AMM 24-41-00-862-002.
[Rev.8 from Aug 2018] 2026.04.04 04:33:38 UTC
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