Toshiba MML-AP0124H2UL Service Manual page 66

Check code
Main
Outdoor 7-segment display
remote
Check
Sub-code
control
code
01: TS condition
P15 P15
02: TD condition
P17 P17 —
Detected outdoor unit
No.
P19 P19
P20 P20 —
Location
of
Description System status
detection
I/F Gas All stop
leakdetection
(TS1 condition)
I/F Gas leak All stop
detection
(TD condition)
I/F Discharge All stop
temperature
TD2 trouble
I/F 4-way valve All stop
reversing
trouble
I/F Activation of All stop
high-pressure
protection
Trouble detection
condition(s)
Protective shutdown due to
sustained suction temperature at or
above judgment criterion for at
least 10 minutes is repeated four
times or more.
<TS trouble judgment criterion>
In cooling operation: 140°F (60°C)
In heating operation: 104°F (40°C)
Protective shutdown due to
sustained discharge temperature
(TD1 or TD2) at or above 226.4°F
(108°C) for at least 10 minutes is
repeated four times or more.
Discharge temperature (TD2)
exceeds 239°F (115°C).
Abnormal refrigerating cycle data is
collected during heating operation.
<During cooling operation>
Pd sensor detects pressure
equal to or greater than 558.25 psi
(3.85 MPa).
<During heating operation>
Pd sensor detects pressure equal
to or greater than 522 psi (3.6 MPa).
– 66 –
Check items (locations)
• Check for insufficiency in
refrigerant quantity.
• Check outdoor service valves
(gas side, liquid side) to confirm
full opening.
• Check PMVs (PMV1, 3) for
clogging.
• Check resistance characteristics
of TS1 sensor.
• Check for defect in 4-way valve.
• Check SV4 circuit for leakage
• Check for insufficiency in
refrigerant quantity.
• Check PMVs (PMV 1, 3) for
clogging.
• Check resistance characteristics
of TD1 and TD2 sensors.
• Check indoor filter for clogging.
• Check piping for clogging.
• Check SV4 circuit (for leakage or
coil installation trouble).
• Check outdoor service valves
(gas side, liquid side) to confirm
full opening.
• Check outdoor PMVs (PMV1, 3, 4)
for clogging.
• Check resistance characteristics
of TD2 sensor.
• Check for defect in 4-way valve.
• Check SV4 circuit for leakage.
• Check SV4 circuit (for wiring or
installation trouble involving SV41
and SV42).
• Check for defect in main body of
4-way valve.
• Check for coil defect in 4-way
valve and loose connection of its
connector.
• Check resistance characteristics
of TS1 and TE1,TE2 sensors.
• Check output voltage
characteristics of Pd and Ps
pressure sensors.
• Check for wiring trouble involving
TE1 and TL1 sensors.
• Check for defect in Pd pressure
sensor.
• Check 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 PMV (PMV1, 3, 4)
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 defect 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.