Fujitsu AOY90 User Manual

PCB LED
1 to 6
LCD
LED display
Cause
Remote
controller
Indoor
unit
Outdoor
unit
– 120–
Controlling
display
(Operation
display LED
flashing)
Controlling
display
(Defrosting
operation)
Normal
display
Defrosting operation in progress Outdoor unit heat exchanger
extremely cold (-5 C or less)
repeats 3 seconds ON, 1 second
OFF cycle.
Error display
(Outdoor unit
error display)
Error display
(Compressor
error)
Error display
(Outdoor
unit error)
Compressor faulty
Voltage (AC380-415V) is applied
to secondary side of power line,
but compressor does not operate.
While checking for a compressor
error, the other compressors
perform the backup operation.
Resistance across compressor
wires : 5 each.

Compressor faulty
Compressor lock
When the compressor does not
operate, measure the resistance
across the compressor wires and
the ground resistance.
(When the compressor is locked,
the resistance across the wires
and the ground resistance will be
the normal value, the same as
when the compressor is stopped.)
When this trouble occurs, the oil
in the compressor has
deteriorated (changed to black
color).
Compressor faulty
Compressor motor burned
When the compressor does not
operate, measure the resistance
across the compressor wires and
the ground resistance.
(When the motor is burned, the
resistance across wires
increases / open and the ground
resistance drops.)
When this trouble occurs, the oil
does not deteriorate.
Therefore, operation can be
continued, but since the
possibility of electric leakage is
high, the compressor power line
must always be disconnected.
Error display
(Outdoor
unit error)
Error display
(Reverse
phase error)
Error display
(Outdoor
unit error)
Compressor faulty
The compressor operates
normally, but the high pressure
does not rise.
Reverse phase
The compressor wiring is red-R,
white-S, and black-T.
Error display
(Communi-
cation
error)
Error display
(Communi-
cation
error)
Error display
(Communi-
cation
error)
Normal after power reset.
Outdoor unit communication
PCB faulty.
When outdoor unit power reset
is repeated, a communication
error is generated.
When the display returns to
normal (not communicating)
after reset, the communication
PCB or communication line is
abnormal.
No display
or error
display
(Cannot be
specified)
Cannot be
specified.
No display
or error
display
(Cannot be
specified)
Indoor unit fan
not operating.
Indoor unit
makes an
abnormal
sound.

Indoor unit control PCB faulty. The symptom has many
branches, depending on the
error contents, and there is no
effective check method.
When the PCB or the connection
wiring is faulty, operation can
often be restored by replacing
the PCB.
Cannot be
specified.
No display or
error display
(Cannot be
specified)
Cannot be
specified.
Indoor unit fan
not operating.
Indoor unit
makes an
abnormal
sound.

Outdoor unit control PCB faulty.
The symptom has many
branches, depending on the
error contents, and there is no
effective check method.
When the PCB or the connection
wiring is faulty, operation can
often be restored by replacing
the PCB.
Remarks
Check method
(Error state check method)
Operation display LED
Compressor motor burned
Compressor lock
Therefore, long-term operation
is impossible.
(Another compressor locks.)
Symptom that
can occur other
than title
1
2
1
bottom of set temperature display
position.
DEFROST is displayed at
2
Body
LED

Fujitsu AOY90 Specifications

General

Brand	Fujitsu
Model	AOY90
Category	Air Conditioner
Language	English