Toshiba MCY-MHP0404HT, Service Manual, Page: 115 / 184

125
P15 P15
01: TS
condition
I/F Gas
leakdetection
(TS condition)
All stop Protective shutdown due to
sustained suction
temperature at or above
judgment criterion
for at least 10 minutes is
repeated four times or more.
<TS error judgment criterion>
In cooling operation: 60 °C
In heating operation: 40 °C
• Check for insufficiency in
refrigerant quantity.
• Check outdoor service
valves (gas side, liquid
side) to confirm full
opening.
• Check outdoor PMV for
clogging.
• Check resistance
characteristics of TS
sensor.
• Check for defect in 4-way
valve.
• Check SV4, SV5 circuit for
leakage
02: TD
condition
I/F Gas leak
detection
(TD condition)
All stop Protective shutdown due to
sustained discharge
temperature (TD) at or above
108 °C for at least 10 minutes
is repeated four times or
more.
• Check for insufficiency in
refrigerant quantity.
• Check outdoor PMV for
clogging.
• Check resistance
characteristics of TD
sensor.
• Check indoor filter for
clogging.
• Check piping for clogging.
• Check SV4 circuit (for
leakage or coil installation
error).
P19 P19
Detected
outdoor unit
No.
I/F 4-way valve
reversing error
All stop Abnormal refrigerating cycle
data is collected during
heating operation.
• 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 TS and
TE sensors.
• Check output voltage
characteristics of Pd and
Ps pressure sensors.
• Check for wiring error
involving TE and TL
sensors.
P20 P20 –
I/F Activation of
high-pressure
protection
All stop Pd sensor detects pressure
equal to or greater than 3.6
MPa.
• 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 for
clogging.
• Check indoor / outdoor
heat exchangers 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 error.
• Check for faulty operation
of check valve in discharge
pipe convergent section.
• Check for refrigerant
overcharging.
Location
of
detection
Description System status
Error detection
condition(s)
Check items (locations)
Main
remote
controller
Outdoor 7-segment display
Check
code
Sub-code
• Check SV5 valve circuit.
• Check gas balancing SV4
valve circuit.
• Check for short-circuiting
of outdoor suction /
discharge air flows.
• Check SV2 circuit for
clogging.
Check code
114