Toshiba MMU-UP0051MH-E(TR) Service Manual page 113

Check code
Main Outdoor 7-segment display
remote
Check
Sub-code
controller
code
Detected indoor
address
P10 P10
P11 — —
P12 — —
P13 P13 —
01: TS condition
P15 P15
02: TD condition
Location
Description
of
detection
Indoor unit Indoor overflow All stop
trouble
I/F Outdoor heat All stop
exchanger
freeze trouble
Indoor unit Indoor fan Stop of
motor trouble corresponding
unit
I/F Outdoor liquid All stop
backflow
detection
trouble
I/F Gas leak All stop
detection
(TS1 condition)
I/F Gas leak All stop
detection
(TD condition)
– 113 –
Check code detection
System status
condition(s)
• Float switch operates.
• Float switch circuit is
open-circuited or
disconnected at connector.
• Outdoor heat exchanger
remaining frost detection
has occurred eight times
or more due to abnormal
frost formation in heating
operation.
• Motor speed
measurements
continuously
deviate from target
value.
• Overcurrent
protection is
activated.
<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.
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
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 items (locations)
• 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.
• 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.
• 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).
• 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
• 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
• 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).