W DOC AIRBUS | TSM A320F

AFT Drainmast-Heater Failure

TASK 30-71-00-810-802-A
AFT Drainmast-Heater Failure

1. Possible Causes
  • CONTROL UNIT, WASTE WATER ICE PROTECTION- [15DU]
  • DRAINMAST "F" [14DU]
  • wiring
  • DEU-B [300RH5]
  • DECODER/ENCODER UNIT B [300RH7]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
TSM TASK 23-73-00-810-827-A
DEU-B - Fault in DEU-B 300RHx with connected systems/devices
AMM 23-73-47-000-001
Removal of the Decoder/Encoder Unit B (300RH)
AMM 23-73-47-400-001
Installation of the Decoder/Encoder Unit B (300RH)
AMM 30-71-00-710-001
Operational Test of the Drainmast Ice Protection
AMM 30-71-00-740-001
BITE Test of the Drainmast Ice Protection (through CIDS SYSTEM/TEST)
ASM 307101
AMM 30-71-34-000-001
Removal of the Waste-Water Ice-Protection Control-Unit
AMM 30-71-34-400-001
Installation of the Waste-Water Ice-Protection Control-Unit
AMM 30-71-51-000-001
Removal of the Drain Mast
AMM 30-71-51-400-001
Installation of the Drain Mast
3. Fault Confirmation
Subtask 30-71-00-710-052-A ** ON A/C NOT FOR ALL
A. Do the operational test of the waste-water ice-protection system AMM 30-71-00-710-001.
Subtask 30-71-00-710-052-B ** ON A/C NOT FOR ALL
A. Do the BITE Test of the Drainmast Ice Protection (via CIDS System/Test) AMM 30-71-00-740-001
4. Fault Isolation
Subtask 30-71-00-810-052-A ** ON A/C NOT FOR ALL
A. If the PTP 110RH shows the fault message DRAINMASTS HEATER AFT:
   (1) Do the operational test of CONTROL UNIT 15DU AMM 30-71-00-710-001.
   (2) If the green HTR LED of CONTROL UNIT 15DU does not come on:
     (a) Replace CONTROL UNIT, WASTE WATER ICE PROTECTION- [15DU] AMM 30-71-34-000-001 AMM 30-71-34-400-001.
     (b) If the fault continues:
       1 Do a check of the resistance value of the drainmast heater and the temperature sensor. Refer to the resistance values in the tables.
  • Resistance values of the sensor:
TEMPERATURE
RESISTANCE VALUE IN OHM
-10deg C (14deg F)
1784+-9
0deg C (32deg F)
1854+-8
+10deg C (50deg F)
1926+-6
+20deg C (68deg F)
2000+-5
+30deg C (86deg F)
2076+-5
+40deg C (104deg F)
2153+-6

  • Resistance values of the heater:
PART NUMBER
RESISTANCE VALUE IN OHM
4-60000H800-00
57+-3
4-60000H840-00
57+-3
4-60000H880-00
118+-5
4-60000H882-00
4-60000H883-00
118+-5
118+-5

     (c) If the fault continues:
       1 Replace DRAINMAST "F" [14DU] or only the cover or the heater tube assembly AMM 30-71-51-000-001 and AMM 30-71-51-400-001.
     (d) If the fault continues:
       1 Do a check and repair of the wiring between:
  • CONTROL UNIT 15DU connector A/8 and DRAINMAST 14DU connector A/B
  • DRAINMAST 14DU connector A/C and GND
  • DRAINMAST 14DU connector A/A and GND ASM 307101.
   (3) If the green HTR LED of CONTROL UNIT 15DU comes on:
     (a) Do a check and repair of the wiring if necessary between:
  • CONTROL UNIT 15DU connector A/11 and DEU-B 300RH5 or DEU-B 300RH7 connector C/34
  • CONTROL UNIT 15DU connector A/14 and CB 11DU
  • CONTROL UNIT 15DU connector A/15 and GND ASM 307101.
     (b) If the fault continues:
       1 Replace DEU-B [300RH5] , if installed
or
DECODER/ENCODER UNIT B [300RH7] , if installed
AMM 23-73-47-000-001 and AMM 23-73-47-400-001.
     (c) If the fault continues:
       1 Do the trouble shooting procedure for the fault in DEU-B 300RH5 or DEU-B 300RH7 with connected Systems/Devices (Ref. TSM TASK 23-73-00-810-827).
Subtask 30-71-00-810-052-B ** ON A/C NOT FOR ALL
A. If the BITE test gives the maintenance message DRAINMAST HEATER AFT
   (1) If the green HTR LED of CONTROL UNIT 15DU does not come on:
     (a) Replace CONTROL UNIT, WASTE WATER ICE PROTECTION- [15DU] AMM 30-71-34-000-001 and AMM 30-71-34-400-001.
     (b) If the fault continues:
       1 Do a check of the resistance value of the drainmast heater and the temperature sensor. Refer to the resistance values in the tables.
  • Resistance values of the temperature sensor:
TEMPERATURE
RESISTANCE VALUE IN OHM
-10deg C (14deg F)
1784+-9
0deg C (32deg F)
1854+-8
+10deg C (50deg F)
1926+-6
+20deg C (68deg F)
2000+-5
+30deg C (86deg F)
2076+-5
+40deg C (104deg F)
2153+-6

  • Resistance values of the heater:
PART NUMBER
RESISTANCE VALUE IN OHM
4-60000H800-00
57+-3
4-60000H840-00
57+-3
4-60000H880-00
118+-5
4-60000H882-00
118+-5
4-60000H883-00
118+-5

     (c) If the fault continues:
       1 Replace DRAINMAST "F" [14DU] or only the cover or the heater tube assembly AMM 30-71-51-000-001 and AMM 30-71-51-400-001.
     (d) If the fault continues:
       1 Do a check and repair the wiring between:
  • CONTROL UNIT 15DU connector A/8 and DRAINMAST 14DU connector A/B
  • DRAINMAST 14DU connector A/C and GND
  • DRAINMAST 14DU connector A/A and GND ASM 307101.
   (2) If the green HTR LED of CONTROL UNIT 15DU comes on:
     (a) Do a check and repair the wiring if necessary between:
  • CONTROL UNIT 15DU connector A/11 and DEU-B 300RH5 or DEU-B 300RH7 connector C/43
  • CONTROL UNIT 15DU connector A/14 and CB 11DU
  • CONTROL UNIT 15DU connector A/15 and GND ASM 307101.
     (b) If the fault continues:
       1 Replace [300RH5] , if installed
or
DECODER/ENCODER UNIT B [300RH7] , if installed
AMM 23-73-47-000-001 and AMM 23-73-47-400-001.
     (c) If the fault continues:
       1 Do the trouble shooting procedure for the fault in DEU-B 300RH5 or DEU-B 300RH7 with connected Systems/Devices (Ref. TSM TASK 23-73-00-810-827).
Subtask 30-71-00-710-053-A
B. Do the test as given in Para. 3.A.
5. Close-up
Subtask 30-71-00-860-051-A
A. Put the aircraft back to its initial configuration.
[Rev.8 from Aug 2018] 2026.04.04 04:29:45 UTC
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