Omega OTEC IEWB Series User manual

IEWB/ICHB Series
208~230V/1/50-60Hz
19 SEER Hygienic Mini Split
Service Manual

Content
1. Safety Precautions.........................................................................................................................1
2. Troubleshooting ...........................................................................................................................4
2.1 Safety caution....................................................................................................................4
2.2 Error diagnosis and solution without error code.................................................................4
2.3 Error code list....................................................................................................................6
2.4 Spot check.........................................................................................................................7
2.4 Troubleshooting by error code ...........................................................................................8
Indoor unit error ..............................................................................................................8
2.4.1 E1 (IDU) Communication failure between indoor and outdoor unit.........................8
2.4.2 E2, E3, E4 (IDU) temperature sensor fault ..............................................................8
2.4.3 E6 (IDU) Zero-crossing detection fault ...................................................................9
2.4.4 E7 (IDU) EEPROM error........................................................................................9
2.4.5 E8 (IDU) PG fan motor stall protection...................................................................9
2.4.6 E9 (IDU) Communication fault of wired controller .................................................10
2.4.7 HC Room card port disconnected port.....................................................................10
Outdoor unit error............................................................................................................11
2.4.8 E2 (ODU) Communication failure between indoor and outdoor unit .......................11
2.4.9 E4, E5, E6 (ODU) temperature sensor fault.............................................................11
2.4.10 E9 (ODU) AC over-voltage / under-voltage protection..........................................11
2.4.11 E10 (ODU) Outdoor unit EEPROM error..............................................................11
2.4.12 E11 (ODU) Indoor unit fan motor fault .................................................................11
2.4.13 E12 (ODU) IPM temperature sensor fault .............................................................11
2.4.14 E2x Outdoor unit fan motor fault ..........................................................................12
2.4.15 H2x Compressor fault ...........................................................................................12
2.4.16 P3 Primary / secondary over-current protection.....................................................12
2.4.17 P4 High discharge temperature protection .............................................................13
2.4.18 P5 High condenser temperature protection ............................................................13
2.4.19 P6 IPM module fault.............................................................................................13
2.4.20 P7 IDU anti-frosting protection.............................................................................14
2.4.21 P8 High IPM temperature protection.....................................................................14
2.4.22 P9 Outdoor unit fan motor stall protection.............................................................15
2.4.23 P11 High evaporator temperature protection .........................................................15

1
1. Safety Precautions
Read Safety Precautions Before Installation
Incorrect installation due to ignoring instructions can cause serious damage or injury.
The seriousness of potential damage or injuries is classified as either a WARNING or CAUTION.
This symbol indicates that ignoring instructions may cause death or serious injury.
This symbol indicates that ignoring instructions may cause moderate injury to
your or damage to your appliance or other property.
This appliance can be used by children aged from 8 years and above and persons with reduced physical,
sensory or mental capabilities or lack of experience and knowledge if they have been given supervision
or instruction concerning use of the appliance in a safe way and understand the hazards involved.
Children shall not play with the appliance. Cleaning and user maintenance shall not be made by
children without supervision.
I. Installation Warnings
Ask an authorized dealer to install this air conditioner. Inappropriate installation may cause
water leakage, electric shock, or fire.
All repairs, maintenance and relocation of the unit must be performed by an authorized service
technician. Inappropriate repairs can lead to serious injury or product failure.
II. Warnings for product use
If an abnormal situation arises (like a burning smell), immediately turn off the unit and pull
the power plug.
Call your dealer for instructions to avoid electric shock, fire or injury.
Do not insert fingers, rods or other objects into the air inlet or outlet. This may cause injury,
since the fan may be rotating at high speeds.
Do not use flammable sprays such as hair spray, lacquer or paint near the unit. This may cause
fire or combustion.
Do not operate the air conditioner in places near or around combustible gases. Emitted gas
may collect around the unit and cause explosion.
Do not operate the air conditioner in a wet room (e.g., bath room or laundry room). This can
cause electrical shock and cause the product to deteriorate.
Do not expose your body directly to cool air for a prolonged period of time.

2
III. Electrical Warnings
Only use the specified power cord. If the power cord is damaged, it must be replaced by the
manufacturer or certified service agent.
Keep power plug clean. Remove any dust or grime that accumulates on or around the plug.
Dirty plugs can cause fire or electric shock.
Do not pull power cord to unplug unit. Hold the plug firmly and pull it from the outlet. Pulling
directly on the cord can damage it, which can lead to fire or electric shock.
Do not use an extension cord, manually extend the power cord, or connect other appliances
to the same outlet as the air conditioner. Poor electrical connections, poor insulation, and
insufficient voltage can cause fire.
IV. Cleaning and Maintenance Warnings
Turn off the device and pull the plug before cleaning. Failure to do so can cause electrical
shock.
Do not clean the air conditioner with excessive amounts of water.
Do not clean the air conditioner with combustible cleaning agents. Combustible cleaning
agents can cause fire or deformation.
⚫If the air conditioner is used together with burners or other heating devices, thoroughly ventilate
the room to avoid oxygen deficiency.
⚫Turn off the air conditioner and unplug the unit if you are not going to use if for a long time.
⚫Turn off and unplug the unit during storms.
⚫Make sure that water condensation can drain unhindered from the unit.
⚫Do not operate the air conditioner with wet hands. This may cause electric shock.
⚫Do not use device for any other purpose than its intended use.
⚫Do not climb onto or place objects on top of the outdoor unit.
⚫Do not allow the air conditioner to operate for long periods of time with doors or windows open,
or if the humidity is very high.

3
2 Specifications
2.1 Model Reference
Refer to the following table to determine the specific indoor and outdoor unit model number of your
purchased equipment.
Hygienic Heat pump
Indoor unit model Outdoor unit model Capacity
(Btu/h) Power supply
IEWB009J1A-CWJ026CWA ICHB009J1A-CTJ026GFA 9K 115V/60Hz/1Ph
IEWB012J1A-CWJ035CWA ICHB012J1A-CTJ035GFA 12K
IEWB009J0A-CWJ026CWA ICHB009J0A-CTJ026GFA 9K
208~230V/50-60Hz/1Ph
IEWB012J0A-CWJ035CWA ICHB012J0A-CTJ035GFA 12K
IEWB018J2A-CWJ053CWA ICHB018J0A-CTJ053GFA 18K
IEWB024J0A-CWJ070CWA ICHB024J0A-CTJ070GFA 24K

4
2 Troubleshooting
2.1 Safety caution
⚫Be sure to turn off all power supplies or disconnect all wires to avoid electric shock. While
checking indoor/outdoor PCB, please equip oneself with antistatic gloves or wrist strap to avoid
damage to the board.
⚫Electricity remains in capacitors even when the power supply is off.
⚫Ensure the capacitors are fully discharged before troubleshooting.
(Test the voltage between P and N on back of the main PCB with multimeter. If the voltage is lower
than 36V, the capacitors are fully discharged.)
2.2 Error diagnosis and solution without error code
Some phenomena are easily thought as error, but actually not.
Phenomena
Reasons
The unit can’t be restarted just after shut down.
(RUN lamp is ON)
Restart stop for 3 minutes after shut down to
protect the unit. Three minutes protection timer
incorporated in the microcomputer actuates
automatically. Except that power is connected,
this function does not actuate.
Air is not blown out at starting of heating
operation.
Air blow is stopped to prevent blowing out cold
air when the indoor heat exchanger is not
warmed enough. (2 to 5 min)
Air is not blown out for 6 to 12 min in heating
mode
When outdoor temperature is low and humidity
is high, the unit sometimes performs defrosting
mode automatically. Please wait. During
defrosting mode, water or steam are raising from
the outdoor unit.
The unit will not stop blowing out the air
immediately after shut down at cooling operation
(some model)
The drying function may be activated, please
wait for the end of the operation or use the
remote control to turn off the drying function.
The louver will not close down until after 30
seconds.
Air is not blown out at dehumidification
operation.
Indoor fan is sometimes stopped to prevent
moisture from evaporating and to save energy.

5
Mist is blown out.
When the room humidity is relatively high, the
cooling operation or heating operation defrosting
ends, the air outlet may blow out water mist,
which is a normal physical phenomenon.
Water may on the air outlet grilles.
When the ambient humidity is relatively
high, water droplets will be generated in the
air outlet, panel and other parts, which is a
normal physical phenomenon;
Long-term cooling operation in an open
space will produce water droplets, please
close the doors and windows.
If the panel is not tightly closed, causing air
leakage, water droplets may be generated on
the panel. Please close the panel securely.
Stop after some time running
Reach setting temperature
In defrosting mode
Timer OFF is set
Strange sound in indoor unit
The dust filter accumulates too much dust.
Please clean the dust filter in time;
When the plastic parts of the indoor unit
expand and contract with heat, it may
produce frictional sound.
After the "TURBO" function is turned on,
the wind noise is loud.
The indoor unit panel is not closed tightly or
the air inlet is obstructed. Please close the
panel again or remove the obstruction of the
air inlet.
Strange sound in outdoor unit
The sound of refrigerant flowing when it is
running or just stopped, which is a normal
phenomenon.
After running for a period of time, a "puff"
sound is made, which is the sound of the
four-way valve reversing when the outdoor
unit turns to defrosting mode, which is a
normal phenomenon.

6
2.3 Error code list
2.2.1 Indoor unit error code
Definitions of malfunction
Error code
Communication failure between indoor and outdoor unit
E1
T1 room temperature sensor fault
E2
T2 temperature sensor fault
E3
T2B temperature sensor fault
E4
Outdoor unit fault
E5
Zero-crossing detection fault
E6
EEPROM error
E7
PG fan motor stall protection
E8
Communication fault of wired controller
E9
Room card port disconnected port
HC
When it shows E5, press to show more error code.
Definitions of malfunction
Error code
Communication failure between indoor and outdoor unit
E2
T4 ambient temperature sensor fault
E4
T5 discharge temperature sensor fault
E5
T3 condenser pipe temperature sensor fault
E6
Indoor unit EEPROM error
E7
AC over-voltage / under-voltage protection
E9
Outdoor unit EEPROM error
E10
Indoor unit fan motor fault
E11
IPM temperature sensor fault
E12
Outdoor unit fan motor fault
E2x
Compressor fault
H2x
PFC fault
H3x

7
Primary / secondary over-current protection
P3
High discharge temperature protection
P4
High condenser temperature protection
P5
IPM module fault
P6
IDU anti-frosting protection
P7
High IPM temperature protection
P8
Outdoor unit fan motor stall protection
P9
High evaporator temperature protection
P11
DC bus low voltage protection
L1
DC bus high voltage protection
L2
MCE fault / sync / compressor start fault
L4
Zero speed protection
L5
Phase sequence error protection
L7
Compressor stall fault
L8
Frequency limitation because of voltage
LA
Frequency limitation because of evaporator temperature
LB
Frequency limitation because of condenser temperature
LC
Frequency limitation because of discharge temperature
LD
Frequency limitation because of high IPM temperature
LE
Frequency limitation because of current
LF
2.4 Spot check
⚫Method 1: After powering on 5s, long press the button in indoor unit PCB for 5s, to enter spot
check. And then short press this button to read more parameters.
⚫Method 2: After powering on, press “up & down swing” and “left & right swing” button alternately
5 times within 10 seconds to enter spot check. Press “up & down swing” and “left & right swing”
button to read more parameters.
⚫Spot check table:

8
No.
Content
0-
Setting temperature
1-
Indoor temperature (T1),
2-
Indoor unit evaporator temperature (T2 or T2B)
3-
EEPROM code
4-
Software code
5-
Outdoor unit error code
6-
Outdoor unit running frequency
7-
Outdoor unit condenser temperature (T3)
8-
Outdoor ambient temperature (T4)
9-
Indoor unit fan speed (f0 means 1500rpm, a1 means 1010rpm)
2.4 Troubleshooting by error code
Indoor unit error
2.4.1 E1 (IDU) Communication failure between indoor and outdoor unit
Description: the indoor unit didn’t receive feedback from outdoor unit within 1 minute.
Possible reason:
Bad connection of communication wire
Fault indoor or outdoor unit PCB
Troubleshooting and repair:
a) Check if the wiring connection between outdoor and indoor unit is loose.
b) Power off and then repower on the unit after 3 minutes. If error code disappear, problem is solved.
If not, go to next step.
c) Measure the DC voltage between P and N on back of the main PCB with multi meter.
2.4.2 E2, E3, E4 (IDU) temperature sensor fault
Description: the sampling voltage is lower than 0.06V or higher than 4.94V.
Possible reason:
Open circuit or short circuit of relevant port.
Faulty temperature sensor