Toshiba MMD-AP0726HP-UL Service Manual page 64

Check code
Outdoor 7-segment display
Main
remote
Check
Sub-code
control
code
F29 –
F31 F31
01: Compressor 1 side
02: Compressor 2 side
H01 H01
01: Compressor 1 side
02: Compressor 2 side
H02 H02
01: Compressor 1 side
02: Compressor 2 side
H03 H03
H05 H05
H06 H06
*1 Total shutdown in case of header unit
Continued operation in case of follower unit
Location
of Description
detection
Indoor Other indoor
trouble
– unit
I/F Outdoor
EEPROM
–
trouble
IPDU Compressor
breakdown
IPDU Compressor
trouble (lockup)
MG-CTT
trouble
IPDU Current
detection
circuit trouble
I/F TD1 sensor
miswiring
(incomplete
insertion)
–
I/F Activation of
low-pressure
protection
–
Trouble detection
System
status condition(s)
Stop of Indoor P.C. board does not
corresponding operate normally.
unit
All stop *1 Outdoor P.C. board (I/F)
does not operate normally.
All stop Inverter current detection
circuit detects overcurrent
and shuts system down.
All stop Overcurrent is detected
several seconds after
startup of inverter
compressor.
All stop Current flow of at least
specified magnitude is
detected despite inverter
compressor having been
shut turned off.
All stop Discharge temperature of
compressor 1 (TD1) does
not increase despite
compressor being in
operation.
All stop Low-pressure Ps sensor
detects operating
pressure lower than
2.9psi(0.02MPa)
- 64 -
Check items (locations)
• Check for defect in indoor P.C.
board (faulty EEPROM)
• Check power supply voltage.
• Check power supply noise.
• Check for defect in outdoor
P.C. board (I/F).
• Check power supply voltage.
(AC460V ± 10%).
• Check for defect in
compressor.
• Check for possible cause of
abnormal overloading.
• Check for defect in outdoor
P.C. board (A3-IPDU).
• Check for defect in
compressor.
• Check power supply voltage.
(AC460V ± 10%).
• Check compressor system
wiring, particularly for open
phase.
• Check connection of
connectors/terminals on A3-
IPDU P.C. board.
• Check conductivity of case
heater.
(Check for refrigerant
problem inside
compressor.)
• Check for defect in outdoor
P.C. board (A3-IPDU).
• Check outdoor MG-CTT.
• Check current detection circuit
wiring.
• Check defect in outdoor P.C.
board (A3-IPDU).
• Check installation of TD1
sensor.
• Check connection of TD1
sensor connector and wiring.
• Check resistance
characteristics of TD1 sensor.
• Check for defect in outdoor
P.C. board (I/F).
• Check service valves to
confirm full opening
(both gas and liquid sides).
• Check outdoor PMVs for
clogging (PMV1, 3).
• Check for defect in SV2 or SV4
circuits.
• Check for defect in low-
pressure Ps sensor.
• Check indoor filter for clogging.
• Check valve opening status of
indoor PMV.
• Check refrigerant piping for
clogging.
• Check operation of outdoor fan
(during heating).
• Check for insufficiency in
refrigerant quantity.
MG-CTT: Magnet contactor