Toshiba MMD-AP0726HP-UL Service Manual page 69

Check code
Outdoor 7-segment display
Main
remote
Check
Sub-code
control
code
01: Compressor 1 side
02: Compressor 2 side
P04 P04
00:
01: Compressor 1 side
02: Compressor 2 side
P05 P05
01: Compressor 1 side
02: Compressor 2 side
P07 P07
Detected indoor address
P10 P10
P12 – –
Location
of Description
detection
IPDU Activation of high-
pressure SW
I/F Detection of open
phase/phase sequence
Inverter DC voltage
(Vdc) trouble
(compressor)
MG-CTT trouble
Heat sink overheating
IPDU
trouble
I/F
Indoor overflow trouble
Indoor
unit
Indoor Indoor fan motor
trouble
unit
- 69 -
Trouble detection
System
status condition(s)
All stop High-pressure SW is
activated.
All stop • Open phase is
detected when
power is turned
on.
• Inverter DC
voltage is too high
(overvoltage) or
too low
(undervoltage).
All stop Temperature sensor
built into IPM (TH) is
overheated.
All stop • Float switch
operates.
• Float switch circuit
is open-circuited
or disconnected at
connector.
Stop of • Motor speed
corresponding measurements
unit continuously
deviate from target
value.
• Overcurrent
protection is
activated.
Check items (locations)
• Check connection of high-
pressure SW connector.
• Check for defect in Pd
pressure sensor.
• Check outdoor service valves
(gas side, liquid side) to
confirm full opening.
• Check for defect in outdoor
fan.
• Check for defect in outdoor
fan motor.
• Check outdoor PMVs (PMV1,
3) for clogging.
• Check indoor/outdoor heat
exchangers for clogging.
• Check for short-circuiting of
outdoor suction/discharge air
flows.
• Check SV2 circuit for
clogging.
• Check for defect in outdoor
P.C. board (I/F).
• Check for trouble in indoor
fan system (possible cause
of air flow reduction).
• Check opening status of
indoor PMV.
• Check indoor-outdoor
communication line for wiring
trouble.
• Check for faulty operation of
check valve in discharge pipe
convergent section.
• Check gas balancing SV4
valve circuit.
• Check SV5 valve circuit.
• Check for refrigerant
overcharging.
• Check for defect in outdoor
P.C. board (I/F).
• Check wiring of outdoor
power supply.
• Check power supply voltage.
• Check outdoor fan system
trouble.
• Check heat sink cooling duct
for clogging.
• Check IPM and heat sink for
thermal performance for faulty
installation.
(e.g. mounting screws and
thermal conductivity)
• Check for defect in A3-IPDU.
(faulty IPM built-in
temperature sensor (TH))
• Check float switch connector.
• Check operation of drain
pump.
• Check drain pump circuit.
• Check drain pipe for clogging.
• Check for defect in indoor
P.C. board.
• Check connection of fan
connector and wiring.
• Check for defect in fan motor.
• Check for defect in indoor
P.C. board.
• Check impact of outside air
treatment (OA).
MG-CTT: Magnet contactor