Toshiba MMU-P0121H Service Manual page 49

Check Detected Check code
code position name
22 Interface High-pressure
protective
operation
89 Interface Indoor capacity
over
8C Interface Outdoor
backup
operation
prohibited
8d Interface Reduction of
No. of
connected
outdoors
8E Interface Excessive No.
of connected
outdoors
8F Interface Fixed-speed
outdoor
address
duplication
93 Indoor Indoor TC1
sensor alarm
Cause Trouble detection
(Position) condition
High pressure Pd sensor detected 3.0MPa
up protection or more
by high-
pressure Pd
sensor
detection value
Total Total capacity of indoor
connected units135% (more than) total
capacity over capacity of outdoor units.
of indoor units
[NOTE]
When this code is displayed
after set up of change when
fault occurred on outdoor
unit, set up "Over capacity
was not detected.".
Turn on SW9 Bit2 on
interface P.C. board of
inverter outdoor unit.
Prohibited Operation mode of the
status of system changed to HEAT
outdoor while backup operation of
backup the outdoor unit was being
operation set up in cooling only model.
No. of No. of connected outdoor
connected units was judged to be less
outdoor unit than No. of units stored in
communication memory of EEPROM
[NOTE]
If this code is displayed
when backup operation of
outdoor error was
performed, set "Alarm
clear".
No. of No. of outdoor units
connected exceeded 5.
outdoor unit
communication
Duplication of Address No. of fixed-speed
manual outdoor unit was duplicated
address switch under condition that
set up of fixed- address set up of outdoor
speed outdoor unit was manual.
Indoor gas • Sensor resistance value
pipe temp. was infinity or zero (Open,
sensor (TC1) Short).
3-46
Check item (Position)
• Check Pd pressure sensor error.
• Check service valve full open.
• Check cause of overload operation.
• Check connection of outdoor fan
connector.
• Check outdoor fan motor, running
capacitor error.
• Check for blockage in outdoor PMV.
1) Refrigerant choke circuit (PMV A)
2) Liquid line check valve
(Cooling only model)
• Check for blockage in outdoor/indoor
heat exchanger.
• Short-circuit status between outdoor
discharge air and suction air
• Check for blockage in hot gas bypass
SV2 circuit.
• Check outdoor P.C. board (Interface)
error.
• Check open valve status of indoor PMV.
• Check miswiring of communication line
between indoor and outdoor.
• Check indoor unit connection capacity.
• Check indoor unit HP capacity.
• Check outdoor HP set up.
• Check outdoor P.C. board (IPDU) error.
• If there is a unit which outdoor backup
operation is being set up in cooling only
model, heating operation is not
performed.
• Check connection of communication.
• Check communication line between
outdoor units.
• Check power supply OFF (power supply
breaker) of outdoor unit.
• Check outdoor P.C. board (Interface)
error.
• Presence check of outdoor backup set up
• Check connected No. of outdoor units.
(Max. 5 units per 1 system)
• Check communication line between
outdoor units.
• Check outdoor P.C. board (Interface)
error.
• Check address switch set up of fixed-
speed outdoor.
• Check outdoor P.C. board (Interface)
error.
• Check connection of TC1 sensor
connector (CN20)
(Indoor main P.C. board (MCC-1361)).
• Check characteristics of TC1 sensor
resistance value.
• Check failure of indoor main P.C. board
(MCC-1361).