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Error Codes: System Malfunctions
ESIE04-01
3–90
Part 3 – Troubleshooting
3
1
3
4
5
4.2
Malfunction of Transmission between Indoor and Outdoor Unit (
U4
or
UF
)
Error code
U4
or
UF
Error generation
The error is generated when the microprocessor detects that the transmission between the indoor and
the outdoor unit is not normal over a certain amount of time.
Causes
The possible causes are:
P
Wiring indoor-outdoor transmission wire is incorrect
P
Malfunctioning indoor unit PCB
P
Malfunctioning outdoor unit PCB
P
Outside cause (noise...).
Troubleshooting 1
Diagnosis of incorrect or broken/disconnected wiring. If the LEDs on the indoor unit PC board are off,
it indicates that the transmission wiring between indoor and outdoor units may be incorrect or
broken/disconnected.
Caution
Be sure to turn off power switch before connect or disconnect connector, or parts damage may be
occurred.
Does
outdoor unit
microcomputer
normal H1P
flash?
Is
indoor-outdoor
transmission wire
connected
correctly?
Is H1P flashing?
NO
YES
NO
NO
NO
NO (ON or OFF)
NO (OFF)
YES
YES
YES
Is HAP flashing?
Is HBP flashing?
To outdoor unit
(next page)
Is H2P on?
Check of
indoor unit
microcom-
puter
normal
HAP
Check of
indoor unit
transmission
malfunction
HBP
YES
YES
Turn the power supply off
once and then back on.
Failure of indoor unit PCB or
malfunction of power supply
system.
Resets normally.
Could be outside
cause (noise...).
Failure of indoor unit PCB.
Wire correctly.
RZQ - Final.book Page 90 Wednesday, September 8, 2004 8:40 AM
Summary of Contents for RZQ71~125B7V3B
Page 1: ...Service Manual ESIE04 01 RZQ71 125B7V3B Sky Air Inverter R 410A B series ...
Page 2: ......
Page 24: ...ESIE04 01 1 2 Part 1 System Outline 3 1 1 5 ...
Page 32: ...General Outline Outdoor Units ESIE04 01 1 10 Part 1 System Outline 3 1 1 4 5 ...
Page 64: ...General Outline Indoor Units ESIE04 01 1 42 Part 1 System Outline 3 1 1 4 5 ...
Page 76: ...Specifications ESIE04 01 1 54 Part 1 System Outline 3 1 1 4 5 ...
Page 92: ...Functional Diagrams ESIE04 01 1 70 Part 1 System Outline 3 1 1 4 5 ...
Page 94: ...ESIE04 01 1 72 Part 1 System Outline ...
Page 122: ...Wiring Diagrams ESIE04 01 1 100 Part 1 System Outline 3 1 1 4 5 ...
Page 140: ...ESIE04 01 2 2 Part 2 Functional Description 3 1 2 5 ...
Page 162: ...General Functionality ESIE04 01 2 24 Part 2 Functional Description 3 1 2 4 5 ...
Page 200: ...Outdoor Unit Functional Concept ESIE04 01 2 62 Part 2 Functional Description 3 1 2 4 5 ...
Page 202: ...ESIE04 01 3 2 Part 3 Troubleshooting 3 1 3 5 ...
Page 288: ...Error Codes Outdoor Units ESIE04 01 3 88 Part 3 Troubleshooting 3 1 3 4 5 ...
Page 312: ...Additional Checks for Troubleshooting ESIE04 01 3 112 Part 3 Troubleshooting 3 1 3 4 5 ...
Page 314: ...ESIE04 01 4 2 Part 4 Commissioning and Test Run 3 1 4 5 ...
Page 356: ...ESIE04 01 5 2 Part 5 Disassembly and Maintenance 3 1 5 ...
Page 484: ...ESIE04 01 viii Index 3 1 4 5 ...