Toshiba MMY-MUP0801HT7JP, Service Manual

Page: 190 / 309

Check code
Location
of
detection
Description System status
Check code detection
condition(s)
Check items (locations)
• Check full-close operation
of outdoor PMV (1, 2, 3, 4).
• Check for failure in Pd or
Ps sensor.
• Check failure in outdoor
P.C. board (I/F).
• Check capillary of oil
separator oil return circuit
for clogging.
• Check for leakage of check
valve in discharge pipe
Outdoor liquid
backflow
detection
trouble I/F All stop <During cooling operation>
When system is in cooling
operation, high pressure is
detected in the unit that
has been turned off.
<During heating operation>
When system is in heating
operation, low pressure is
detected to be high in unit
that has been turned off.
P13 P13 —
Main
remote
controller
Outdoor 7-segment display
Check
code
Sub-code
• Check for insufficiency in
refrigerant quantity.
• Check outdoor service
valves (gas side, liquid
side) to confirm full
opening.
• Check PMVs (PMV1, 2, 3,
4) for clogging.
• Check resistance
characteristics of TS1
sensor.
• Check for failure in 4-way
valve.
• Check SV4 circuit for
leakage
Gas leak
detection
(TS1 condition) I/F 01: 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 trouble judgment criterion>
In cooling operation: 60 ˚C
In heating operation: 40 ˚C
P15 P15
• Check for insufficiency in
refrigerant quantity.
• Check PMVs (PMV 1, 2, 3,
4) 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).
Gas leak
detection
(TD condition) I/F 02: TD condition All stop Protective shutdown due to
sustained discharge
temperature (TD1 or TD2)
at or above 108 ˚C for at
least 10 minutes is repeated
four times or more.
• Check float switch
connector.
• Check operation of drain
pump.
• Check drain pump circuit.
• Check drain pipe for
clogging.
• Check for failure in indoor
P.C. board.
Indoor overflow
trouble Indoor unit Detected indoor
address All stop • Float switch operates.
• Float switch circuit is
open-circuited or
disconnected at connector.
P10 P10
• Check shortage of
refrigerant.
• Check connection of TE1,
TE2 and TE3 sensors.
• Check resistance
characteristics of TE1,
TE2, and TE3 sensors.
• Check disconnection of
TS1 sensor.
• Check resistance
characteristics of TS1
sensor.
• Check outdoor I/F P.C.
board malfunction.
• Check operation of 4 way
valve.
• Check operation of outdoor
PMV (1, 2, 3).
• Check short circuit from
outlet air to inlet air.
Outdoor heat
exchanger
freeze trouble I/F All stop • Outdoor heat exchanger
remaining frost detection
has occurred eight times
or more due to abnormal
frost formation in heating
operation.
P11 — —
• Check connection of fan
connector and wiring.
• Check for failure in fan
motor.
• Check for failure in indoor
P.C. board.
• Check impact of outside air
treatment (OA).
Indoor fan
motor trouble Indoor unit Stop of
corresponding
unit • Motor speed
measurements
continuously
deviate from target
value.
• Overcurrent
protection is
activated.
P12 — —
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