Datasheet

Self diagnosis description and check point table*
In the event of breakdown, proceed as follows to detect the error code.
1. Press “CHECK” button at the remote control continuously for more than five seconds to turn on diagnosis mode. “_ _” will be displayed at the remote control LCD.
2. By pressing the TIMER “▲” button once, the next error code (if any) will be displayed; press “▼” button once, previous error code will be displayed.
3. If error code displayed matches the error code saved in unit memory (abnormality detected) Indoor PCB will buzzer for 4 seconds to indicate the correct error code.
4. If “CHECK” button is pressed again or without any operation for 30 seconds, the diagnosis mode will turn off.
5. Turn ON the unit and reset the error code by pressing the AC reset.
* Not for CU-5E34NBE
ERROR CODES TABLE
Warning: Electrical power must be disconnected when terminal protective cover is not in place to protect against electrocution.
Diagnosis
Display
Abnormality /
Protection Control
Diagnosis Method Diagnosis Checkpoint
H11 Indoor/Outdoor
abnormal
communication
This trouble display appears when indoor/outdoor unit communication fails to be established after 30 or more
seconds.
Measure the voltages of the indoor/outdoor unit communication cables, and check whether the voltage is being
supplied properly to the outdoor unit or whether it is being returned from the outdoor unit to the indoor units.
H12 Indoor unit capacity
unmatched
This trouble display appears when wrong in the total connection capacity and wrong connection in each capacity.
The trouble is determined within 2 minutes after the power is turned on.
Check the total capacity of the units connected and check that the models are compatible for connection.
H14 Intake air temp. sensor This trouble display appears when the intake air temperature has exceeded above 46°C continuously for 2 minutes
or dropped below -54°C continuously for 5 seconds during operation.
This trouble display appears when a temperature which is impossibly high or low from a normal standpoint has
been detected. Check the sensor, and if open-circuiting (0L or ∞) or short-circuit is not found, defective
contact of the connector is to blame.
H15 Outdoor compressor
temperature sensor
abnormality
— Check the sensor, and if open-circuit (more than 500 k) or (short-circuit) (less than 6.5 k) is not found,
defective contact of the connector is to blame.
H16 Outdoor Current
Transformer
CU-2E: When a value of under 1.5A has been detected for the total current during operation beyond the set
capacity, the compressor operates with its operating frequency controlled to a maximum of 38Hz for 3 minutes,
and if it continues to operate at a total current of under 1.5A for another 3 minutes, its operation stops.
CU-3E/4E: When the total current has dropped below the set current level continuously for 20 seconds during
operation beyond the set capacity, operation is stopped. Three minutes later, operation is started up again, and
when the trouble occurs on 4 successive occasions, the trouble display appears (the timer lamp blinks).
1. Check the refrigerant cycle: Gas may be leaking (the amount of refrigerant is extremely low).
2. Check the control PCB: Check for a broken wire (open circuit) in the current transformer. (If an open circuit
is found, replace the control PCB) In the case of a scroll compressor (DC motor), H16 is detected only when the
regular compressor is operating.
H19 Indoor fan motor
mechanism lock
· High-voltage PWM: When a state in which the fan motor speed is not synchronized with the control signal has been
detected on 7 successive occasions.
· Low-voltage PAM: When the fan lock detection signal has been detected on 7 successive occasions or it has been
detected continuously for 25 seconds or when a state in which the fan motor speed is not synchronized with the control
signal has been detected on 7 successive occasions: The trouble display appears (the timer lamp blinks).
1. Check the nature of the fan lockup trouble.
2. Check for disconnections of the fan motor connectors and for defects in contact, in the fan motor and in the
control PCB.
H23 Indoor heat exchanger
temp. sensor
This trouble display appears when a temperature of under approximately -40°C or above approximately 80°C has
been detected by the heat exchanger temperature sensor continuously for 5 seconds. (This trouble is not detected
during de-icing.)
This trouble display appears when a temperature which is impossibly high or low from a normal standpoint has
been detected. Check the sensor, and if (open-circuit) (0L or ∞) or short-circuit is not found, defective contact
of the connector or a defective control PCB is to blame.
H26 Ionizer Abnormality — 1. Measure the voltages of the indoor unit communication cables, and check whether the voltage is being
supplied properly. 2. Check the ionizer needle and grounding plate is dust free.
H27 Outdoor air temp.
sensor
This trouble display appears when a temperature of under approximately -40°C or above approximately 150°C has
been detected by the outside air temperature sensor for 2 to 5 seconds. (This trouble is not detected during
de-icing.)
This trouble display appears when a temperature which is impossibly high or low from a normal standpoint has
been detected. Check the sensor, and if open-circuiting (0L or ∞) or short-circuit isnot found, defective contact
of the connector or a defective control PCB is to blame.
H28 Outdoor heat exchanger
temp. sensor 1
This trouble display appears when a temperature of under approximately -60°C or above approximately 110°C has
been detected by the heat exchanger temperature sensor for 2 to 5 seconds. (This trouble is not detected during
de-icing.)
This trouble display appears when a temperature which is impossibly high or low from a normal standpoint has
been detected. Check the sensor, and if open-circuiting (0L or ∞) or short-circuit is not found, defective
contact of the connector or a defective control PCB is to blame.
H30 Outdoor discharge pipe
temp. sensor
CU-2E: This trouble display appears when a temperature of under approximately -16°C or above approximately
200°C has been detected by the outlet temperature sensor for 2 to 5 seconds.
CU-3E/4E: Disconnected discharge sensor · When the condensation temperature is higher than the discharge
temperature + (plus) 6°C, a sensor disconnection is detected, operation stops, and the trouble display appears
(the timer lamp blinks).
This trouble display appears when a temperature which is impossibly high or low from a normal standpoint has
been detected. Check the sensor, and if open-circuiting (0L or ∞) or short-circuit is not found, defective
contact of the connector or a defective control PCB is to blame.
H32 Outdoor heat exchanger
temp. sensor 2
(discharge pipe temp.)
This trouble display appears when a temperature of under approximately -60°C or over approximately 110°C has
been detected continuously for 2 to 5 seconds by the outlet temperature sensor of the heat exchanger.
This trouble display appears when a temperature which is impossibly high or low from a normal standpoint has
been detected. Check the sensor, and if open-circuiting (0L or ∞) or short-circuit is not found, defective
contact of the connector or a defective control PCB is to blame.
H33 Indoor / Outdoor wrong
connection
Indoor / Outdoor different model junction, 100V charge into 200V outdoor unit. Check whether the voltage is being supplied properly to the outdoor unit or whether it is being returned from
the outdoor unit to the indoor units.
H34 Outdoor heat sink temp.
sensor
This trouble display appears when a temperature of under -43°C or above 80°C has been detected by the outdoor
unit radiator fin sensor continuously for 2 seconds.
This trouble display appears when a temperature which is impossibly high or low from a normal standpoint has
been detected. Check the sensor, and if open-circuiting (0L or ∞
) or short-circuit is not found, defective
contact of the connector or a defective control PCB is to blame.
H36 Abnormal gas pipe
temp. sensor
This trouble display appears when a temperature of under approximately -45°C or above approximately 149°C has
been detected by the outdoor unit gas side pipe temperature sensor continuously for 2 to 5 seconds.
This trouble display appears when a temperature which is impossibly high or low from a normal standpoint has
been detected. Check the sensor, and if open-circuiting (0L or ∞) or short-circuit is not found, defective
contact of the connector or a defective control PCB is to blame.
H37 Outdoor liquid pipe
temp. sensor
This trouble display appears when a temperature of under -45°C or above 149°C has been detected by the outdoor
unit liquid side pipe temperature sensor continuously for 2 seconds.
This trouble display appears when a temperature which is impossibly high or low from a normal standpoint has
been detected. Check the sensor, and if open-circuiting (0L or ∞) or short-circuit is not found, defective
contact of the connector or a defective control PCB is to blame.
H38 Indoor / Outdoor
mismatch (brand code)
— —
H39 Abnormal indoor
operating unit or
standBy units
This display appears in rooms other than one in which indoor freezing trouble has occurred when the pipes have
been connected incorrectly, when an outdoor expansion valve is defective or when an expansion valve connector
has become disconnected.
—
H41 Abnormal wiring or
piping connection
CU-2E only This display appears when this kind of trouble is detected 3 minutes after a forced cooling operation
was conducted for one room during the initial operation after the power was turned on. It appears when:
· The indoor unit pipe temperature in a room without the capacity supply available at an outside air temperature
above 5°C has dropped by more than 20°C to 5°C or lower 3 minutes after the compressor started up. · The
outdoor unit gas pipe temperature in a room without the capacity supply available has dropped by more than 5°C
to 5°C or lower 3 minutes after the compressor started up.
—
H50 Ventilation failure This display appears when ventilation motor is lock. 1. Check the voltage drop at pin 1 & 2 of CNVENT to have 14Vdc. 2. Check the ventilation hose condition from
ventilation opening until tip cover. 3. Check air fl ow from tip cover by hand.
CHECK
70