Daikin VRVII User manual

Pocket
Manual
Service Diagnosis
Si30 - 701_A

VRV Series
i
Applicable Models ................................................... 2
1. Symptom-based Troubleshooting ................... 12
2. Troubleshooting by Remote Controller ........... 18
2.1 The INSPECTION / TEST Button .....................18
2.2 Self-diagnosis by Wired Remote Controller ......19
2.3 Self-diagnosis by
Wireless Remote Controller ..............................22
2.4 Error Codes and Description ............................24
2.5 Error Codes - Sub Codes ..................................35
3. Troubleshooting by Indication on
the Remote Controller ..................................... 46
3.1 A0 External Protection Device
Abnormality .......................................................46
3.2 A1 PCB Abnormality ..........................................48
3.3 A3 Drain Level Control System (S1L)
Abnormality .......................................................49
3.4 A6 Fan Motor (M1F) Lock, Overload .................52
3.5 A6 Indoor Unit Fan Motor Abnormality ..............55
3.6 A6 Overload/Overcurrent/
Lock of Indoor Unit Fan Motor ..........................57
3.7 A7 Swing Flap Motor (M1S) Abnormality ..........63
3.8 A8 Power Supply Voltage Abnormality ..............66
3.9 A9 Electronic Expansion Valve Coil Abnormality /
Dust Clogging ...................................................68
3.10 AF Drain Level above Limit ................................71
3.11 AJ Capacity Determination Device
Abnormality .......................................................73
3.12 C1 Transmission Error
(between Indoor unit PCB and Fan PCB) .........75
3.13 C4 Thermistor for Liquid Pipe Abnormality ........78
3.14 C5 Thermistor for Gas Pipe Abnormality ...........80
3.15 C6 Combination Abnormality
(between Indoor unit PCB and Fan PCB) .........82
3.16 C9 Thermistor for Suction Air Abnormality ........84

VRV Series
ii
3.17 CA Thermistor for Discharge Air
Abnormality .......................................................86
3.18 CC Humidity Sensor System Abnormality ..........88
3.19 CJ Room Temperature Thermistor in
Remote Controller Abnormality ........................90
3.20 E1 PCB Abnormality ..........................................92
3.21 E2 Earth Leakage by
Leak Detection PCB Assy ................................ 94
3.22 E3 Actuation of High Pressure Sensor ..............97
3.23 E3 Abnormal Discharge Pressure .....................99
3.24 E4 Actuation of Low Pressure Sensor .............102
3.25 E4 Abnormal Suction Pressure .......................104
3.26 E5 Inverter Compressor Motor Lock ................107
3.27 E6 STD Compressor Motor Overcurrent/
Lock ................................................................115
3.28 E7 Outdoor Unit Fan Motor Abnormality .........117
3.29 E9 Electronic Expansion Valve Coil
Abnormality .....................................................130
3.30 F3 Abnormal Discharge Pipe
Temperature ...................................................136
3.31 F6 Refrigerant Overcharged ............................143
3.32 H3 High Pressure Switch System
Abnormality .....................................................148
3.33 H7 Outdoor Unit Fan Motor Signal
Abnormality .....................................................150
3.34 H9 Outdoor Air Thermistor Abnormality ...........155
3.35 HJ Water System Error ....................................159
3.36 J1 High Pressure Sensor Abnormality ............162
3.37 J2 Current Sensor Abnormality .......................165
3.38 J3 Discharge Pipe Thermistor Abnormality .....168
3.39 J4 Heat Exchanger Gas Pipe Thermistor
Abnormality .....................................................170
3.40 J5 Suction Pipe Thermistor Abnormality .........172
3.41 J6 Outdoor Unit Heat Exchanger
Thermistor Abnormality ..................................174
3.42 J7 Liquid Pipe Thermistor Abnormality ...........176
3.43 J8 Thermistor System Abnormality .................178
3.44 J9 Subcooling Heat Exchanger Gas Pipe
Thermistor Abnormality ..................................180
3.45 JA High Pressure Sensor Abnormality ............182

VRV Series
iii
3.46 JA Discharge Pipe Pressure Sensor
Abnormality .....................................................185
3.47 JC Low Pressure Sensor Abnormality .............188
3.48 JC Suction Pipe Pressure Sensor
Abnormality .....................................................191
3.49 L1 Inverter PCB Abnormality ...........................194
3.50 L4 Inverter Radiation Fin Temperature Rise
Abnormality .....................................................202
3.51 L5 Momentary Overcurrent of
Inverter Compressor .......................................207
3.52 L8 Momentary Overcurrent of
Inverter Compressor .......................................213
3.53 L9 Inverter Compressor Startup Failure ..........219
3.54 LC Transmission Error between Inverter and
Control PCB ....................................................226
3.55 P1 Inverter Over-Ripple Protection ..................234
3.56 P4 Inverter Radiation Fin Thermistor
Abnormality .....................................................239
3.57 PJ Field Setting Abnormality after
Replacing Main PCB or Combination of
PCB Abnormality ............................................243
3.58 U0 Refrigerant Shortage Alert .........................250
3.59 U1 Reverse Phase, Open Phase .....................259
3.60 U2 Power Supply Insufficient or
Instantaneous Error ........................................261
3.61 U3 Check Operation is not Executed ...............283
3.62 U4 Transmission Error between
Indoor Units and Outdoor Units ......................285
3.63 U5 Transmission Error between
Remote Controller and Indoor Unit .................298
3.64 U7 Transmission Error
(Across Outdoor Units) ...................................300
3.65 U8 Transmission Error between Main and
Sub Remote Controllers .................................314
3.66 U9 Transmission Error between Indoor and
Outdoor Units in the Same System ................316
3.67 UA Improper Combination of Indoor and
Outdoor Units, Indoor Units and
Remote Controller ..........................................321

VRV Series
iv
3.68 UC Address Duplication of
Centralized Remote Controller .......................335
3.69 UE Transmission Error between
Centralized Remote Controller and
Indoor Unit ......................................................336
3.70 UF System is not Set yet .................................341
3.71 UH System Abnormality,
Refrigerant System Address Undefined .........343

VRV Series
1
Applicable Model Series
Refrigerant Type Product Series Reference
Page
R-22
Air Cooled
VRVII
Inverter
M(A)
2
VRVII-S 3
R-410A
VRVII 4
VRVII-S 5
Water
Cooled VRV-WII 6
Air Cooled
VRVIII
Inverter
P(A)
7
VRVIII-Q 9
VRVIII-S 10
Water
Cooled VRV-WIII 11

VRV Series
2
Applicable Models
1. R-22
1-1. VRVII M(A) Series
Indoor Units Outdoor Units
Type Model Name Symbol
Ceiling Mounted Cassette Type (Double Flow)
FXC 20L 25L 32L 40L 50L 63L 80L - 125L - -
VE
Ceiling Mounted Cassette Type (Multi Flow)
FXF - 25L 32L 40L 50L 63L 80L 100L 125L - -
Ceiling Mounted Cassette Corner Type
FXK - 25L32L40L- 63L- - - - -
Slim Ceiling Mounted Duct Type
FXD-PVE20P25P32P-------- FXD-PVET20P25P32P-------- FXD-MVE 20M 25M 32M 40M 50M 63M - - - - - FXD-MVET 20M 25M 32M 40M 50M 63M - - - - -
Ceiling Mounted Low Silhouette Duct Type
FXYD 20KA 25KA 32KA 40KA 50KA 63KA - - - - -
Ceiling Mounted Built-in Type FXS 20L 25L 32L 40L 50L 63L 80L 100L 125L - - Ceiling Mounted Built-in Type (Rear Suction)
FXYB 20K 25K 32K 40K 50K 63K 80K 100K 125K - - V1
Ceiling Mounted Duct Type FXM - - - 40L 50L 63L 80L 100L 125L 200L 250L
VE
Ceiling Suspended Type FXH - - 32L - - 63L - 100L - Wall Mounted Type FXA 20L 25L 32L 40L 50L 63L - - - Floor Standing Type FXL 20L 25L 32L 40L 50L 63L - - - Concealed Floor Standing Type FXN 20L 25L 32L 40L 50L 63L - - -
Type Model Name Symbol
Heat Pump RXY
5M(A) 8M(A)
10M(A) 12M(A) 14M(A) 16M(A) 18M(A) 20M(A) 22M(A) 24M(A) 26M(A)
Y1(E) YL(E)
TL(E)
28M(A) 30M(A) 32M(A) 34M(A) 36M(A) 38M(A) 40M(A) 42M(A) 44M(A) 46M(A) 48M(A)
Cooling Only RX
5M(A) 8M(A)
10M(A) 12M(A) 14M(A) 16M(A) 18M(A) 20M(A) 22M(A) 24M(A) 26M(A)
Y1
28M(A) 30M(A) 32M(A) 34M(A) 36M(A) 38M(A) 40M(A) 42M(A) 44M(A) 46M(A) 48M(A)

VRV Series
3
1-2. VRVII-S M Series
Indoor Units Outdoor Units
Type Model Name Symbol
Ceiling Mounted Cassette Type (Double Flow) FXC 20L 25L 32L 40L 50L 63L 80L - 125L
VE
Ceiling Mounted Cassette Type (Multi Flow) FXF - 25L 32L 40L 50L 63L 80L 100L 125L Ceiling Mounted Cassette Corner Type FXK - 25L 32L 40L - 63L - - - Slim Ceiling Mounted Duct Type FXD 20M 25M 32M 40M 50M 63M - - - Ceiling Mounted Low Silhouette Duct Type FXYD 20KA 25KA 32KA 40KA 50KA 63KA - - - Ceiling Mounted Built-in Type FXS 20L 25L 32L 40L 50L 63L 80L 100L 125L Ceiling Mounted Built-in Type (Rear Suction) FXYB 20K 25K 32K 40K 50K 63K 80K 100K 125K V1 Ceiling Mounted Duct Type FXM - - - 40L 50L 63L 80L 100L 125L
VE
Ceiling Suspended Type FXH - - 32L - - 63L - 100L - Wall Mounted Type FXA 20L 25L 32L 40L 50L 63L - - - Floor Standing Type FXL 20L 25L 32L 40L 50L 63L - - - Concealed Floor Standing Type FXN 20L 25L 32L 40L 50L 63L - - -
Type Model Name Symbol
Heat Pump RXYM 4M 5M 6M VM Cooling Only RXM 4M5M6M VMT

VRV Series
4
2. R-410A
2-1. VRVII M(A) Series
Indoor Units Outdoor Units
Type Model Name Symbol
Ceiling Mounted Cassette Type (Double Flow)
FXCQ 20M 25M 32M 40M 50M 63M 80M -
125M
--
VE
Ceiling Mounted Cassette Type (Multi Flow)
FXFQ - 25M 32M 40M 50M 63M 80M
100M 125M
--
Ceiling Mounted Cassette Corner Type
FXKQ -
25MA 32MA 40MA
-
63MA
-----
Slim Ceiling Mounted Duct Type
FXDQ-PVE20P25P32P-------- FXDQ-PVET
20P25P32P--------
FXDQ-NAVE 20NA 25NA 32NA 40NA 50NA 63NA
-----
FXDQ-NVET
20N 25N 32N 40N 50N 63N - - - - -
Ceiling Mounted Built-in Type FXSQ 20M 25M 32M 40M 50M 63M 80M
100M 125M
--
Ceiling Mounted Duct Type FXMQ - - -
40MA 50MA 63MA 80MA
100MA 125MA 200MA 250MA
Ceiling Suspended Type FXHQ - -
32MA
--
63MA
-
100MA
---
Wall Mounted Type FXAQ
20MA 25MA 32MA 40MA 50MA 63MA
-----
Floor Standing Type FXLQ
20MA 25MA 32MA 40MA 50MA 63MA
-----
Concealed Floor Standing Type FXNQ
20MA 25MA 32MA 40MA 50MA 63MA
-----
Ceiling Suspended Cassette Type FXUQ ------
71MA
100MA 125MA
-- V1
Connection Unit BEVQ ------
71MA
100MA 125MA
-- VE
Type Model Name Symbol
Heat Pump RXYQ
5MA 8MA
10MA 12MA 14MA 16MA 18MA 20MA 22MA 24MA 26MA
Y1(E) YL(E)
TL(E)
28MA 30MA 32MA 34MA 36MA 38MA 40MA 42MA 44MA 46MA 48MA
Cooling Only RXQ 5MA 8MA
10MA 12MA 14MA 16MA 18MA 20MA 22MA 24MA 26MA
Y1
28MA 30MA 32MA 34MA 36MA 38MA 40MA 42MA 44MA 46MA 48MA
Heat Recovery REYQ 8M 10M 12M 14M 16M 18M 20M 22M 24M 26M 28M Y1B
30M 32M 34M 36M 38M 40M 42M 44M 46M 48M

VRV Series
5
2-2. VRVII-S M Series
Indoor Units Outdoor Units
Type Model Name Symbol
Ceiling Mounted Cassette Type (Double Flow) FXCQ 20M 25M 32M 40M 50M 63M 80M -
125M
VE
Ceiling Mounted Cassette Type (Multi Flow) 600X600 FXZQ 20M 25M 32M 40M 50M - - - - Ceiling Mounted Cassette Type (Multi Flow) FXFQ - 25M 32M 40M 50M 63M 80M
100M 125M
Ceiling Mounted Casette Corner Type FXKQ - 25M 32M 40M - 63M - - - Slim Ceiling Mounted Built-in Type (L.S.P) FXDQ 20N 25N 32N 40N 50N 63N - - - Ceiling Mounted Built-in Type (M.S.P) FXSQ 20M 25M 32M 40M 50M 63M 80M
100M 125M
Ceiling Mounted Duct Type FXMQ - - - 40M 50M 63M 80M
100M 125M
Ceiling Suspended Type FXHQ - - 32M - - 63M -
100M
-
Wall Mounted Type FXAQ 20M 25M 32M 40M 50M 63M - - - Floor Standing Type FXLQ 20M 25M 32M 40M 50M 63M - - - Concealed Floor Standing Type FXNQ 20M 25M 32M 40M 50M 63M - - -
Type Model Name Symbol
Heat Pump RXYMQ 4M5M6M V4A

VRV Series
6
2-3. VRV-WII M Series
Indoor Units Outside Units
Type Model Name Symbol
Ceiling Mounted Cassette Type (Double Flow)
FXCQ 20M 25M 32M 40M 50M 63M 80M -
125M
--
VE
Ceiling Mounted Cassette Type (Multi Flow)
FXFQ - 25M 32M 40M 50M 63M 80M
100M 125M
--
Ceiling Mounted Cassette Corner Type FXKQ -
25MA 32MA 40MA
-
63MA
-----
Slim Ceiling Mounted Duct Type
FXDQ-PVE 20P 25P 32P - - - - - - - - FXDQ-PVET
20P 25P 32P - - - - - - - -
FXDQ-NAVE 20NA 25NA 32NA 40NA 50NA 63NA
-----
FXDQ-NVET
20N 25N 32N 40N 50N 63N - - - - -
Ceiling Mounted Built-in Type FXSQ 20M 25M 32M 40M 50M 63M 80M
100M 125M
--
Ceiling Mounted Duct Type FXMQ - - -
40MA 50MA 63MA 80MA
100MA 125MA 200MA 250MA
Ceiling Suspended Type FXHQ - -
32MA
--
63MA
-
100MA
---
Wall Mounted Type FXAQ
20MA 25MA 32MA 40MA 50MA 63MA
-----
Floor Standing Type FXLQ
20MA 25MA 32MA 40MA 50MA 63MA
-----
Concealed Floor Standing Type FXNQ
20MA 25MA 32MA 40MA 50MA 63MA
-----
Ceiling Suspended Cassette Type FXUQ ------
71MA
100MA 125MA
-- V1
Connection Unit BEVQ ------
71MA
100MA 125MA
-- VE
Type Model Name Symbol
Heat Pump RWEYQ 10M 20M 30M
Y1 YL
TL

VRV Series
7
2-4. VRVIII P(A) Series
Indoor Units
Type Model Name Symbol
Ceiling Mounted Cassette Type (Round Flow)
FXFQ - 25P 32P 40P 50P 63P 80P 100P 125P - - -
VE
Ceiling Mounted Cassette Type (Compact Multi Flow)
FXZQ 20M 25M 32M 40M 50M - - - - - - -
Ceiling Mounted Cassette Type (Double Flow)
FXCQ 20M 25M 32M 40M 50M 63M 80M -
125M
---
Ceiling Mounted Cassette Corner Type
FXKQ -
25MA 32MA 40MA
-
63MA
------
Slim Ceiling Mounted Duct Type
FXDQ-PBVE
20PB25PB32PB---------
FXDQ-PBVET
20PB25PB32PB---------
FXDQ-NBVE
---
40NB 50NB 63NB
------
FXDQ-NBVET
---
40NB 50NB 63NB
------
Ceiling Mounted Built-in Type FXSQ 20M 25M 32M 40M 50M 63M 80M
100MA
125M
---
Ceiling Mounted Duct Type (Middle and High Static Pressure) FXMQ 20P 25P 32P 40P 50P 63P 80P 100P 125P 140P - - Ceiling Mounted Duct Type FXMQ ----------
200MA 250MA
Ceiling Suspended Type FXHQ - -
32MA
--
63MA
-
100MA
----
Wall Mounted Type FXAQ
20MA 25MA 32MA 40MA 50MA 63MA
------
Floor Standing Type FXLQ
20MA 25MA 32MA 40MA 50MA 63MA
------
Concealed Floor Standing Type FXNQ
20MA 25MA 32MA 40MA 50MA 63MA
------
Ceiling Suspended Cassette Type FXUQ ------
71MA
100MA 125MA
--- V1
Connection Unit BEVQ ------
71MA
100MA 125MA
--- VE

VRV Series
8
B

O
utdoor Units
Type Model Name Symbol
Heat Pump RXYQ
5P(A) 8P(A) 10P(A) 12P(A) 14P(A) 16P(A) 18P(A) 20P(A) 22P(A) 24P(A) 26P(A)
Y1(E) YL(E)
28P(A) 30P(A) 32P(A) 34P(A) 36P(A) 38P(A) 40P(A) 42P(A) 44P(A) 46P(A) 48P(A) 50P(A) 52P(A) 54P(A) 5P 8P 10P 12P 14P 16P 18P 20P 22P 24P 26P
TL(E)28P 30P 32P 34P 36P 38P 40P 42P 44P 46P 48P
50P 52P 54P
Cooling Only RXYQ
5P(A) 8P(A) 10P(A) 12P(A) 14P(A) 16P(A) 18P(A) 20P(A) 22P(A) 24P(A) 26P(A)
Y1
28P(A) 30P(A) 32P(A) 34P(A) 36P(A) 38P(A) 40P(A) 42P(A) 44P(A) 46P(A) 48P(A) 50P(A) 52P(A) 54P(A)
Heat Recovery REYQ 8P 10P 12P 14P 16P 18P 20P 22P 24P 26P 28P Y1
30P 32P 34P 36P 38P 40P 42P 44P 46P 48P

VRV Series
9
2-5. VRVIII-Q P Series
Outdoor Units
Type Model Name Symbol
For Replacement
Use RQYQ
8P 10P 12P 14P 16P
Y1
18P 20P 22P 24P 26P
28P 30P 32P 34P 36P
38P 40P 42P 44P 46P
48P

VRV Series
10
2-6. VRVIII-S P Series
Indoor Units Outdoor Units
Type Model Name Symbol
Ceiling Mounted Cassette Type (Double Flow) FXCQ 20M25M32M40M50M63M80M-
125M
VE
Ceiling Mounted Cassette Type (Multi Flow) FXFQ - 25M 32M 40M 50M 63M 80M
100M 125M
Ceiling Mounted Cassette Corner Type FXKQ -
25MA 32MA 40MA
-
63MA
---
Slim Ceiling Mounted Duct Type
FXDQ-PVE20P25P32P------ FXDQ-PVET20P25P32P------ FXDQ-NAVE
20NA 25NA 32NA 40NA 50NA 63NA
---
FXDQ-NVET20N25N32N40N50N63N- - -
Ceiling Mounted Built-in Type FXSQ 20M25M32M40M50M63M80M
100M 125M
Ceiling Mounted Duct Type FXMQ - - -
40MA 50MA 63MA 80MA
100MA 125MA
Ceiling Suspended Type FXHQ - -
32MA
--
63MA
-
100MA
-
Wall Mounted Type FXAQ
20MA 25MA 32MA 40MA 50MA 63MA
---
Floor Standing Type FXLQ
20MA 25MA 32MA 40MA 50MA 63MA
---
Concealed Floor Standing Type FXNQ
20MA 25MA 32MA 40MA 50MA 63MA
---
Ceiling Suspended Cassette Type FXUQ ------
71MA
100MA 125MA
V1
Connection Unit BEVQ ------
71MA
100MA 125MA
VE
Type Model Name Symbol
Heat Pump RXYMA 4P 5P 6P VE Cooling Only RXMQ 4P 5P 6P

VRV Series
11
2-7. VRV-WIII
Indoor Units Outside Units
Type Model Name Symbol
Ceiling Mounted Cassette Type (Round Flow)
FXFQ - 25P 32P 40P 50P 63P 80P 100P 125P - - -
VE
Ceiling Mounted Cassette Type (Compact Multi Flow)
FXZQ 20M 25M 32M 40M 50M - - - - - -
Ceiling Mounted Cassette Type (Double Flow)
FXCQ 20M 25M 32M 40M 50M 63M 80M -
125M
---
Ceiling Mounted Cassette Corner Type
FXKQ -
25MA 32MA 40MA
-
63MA
------
Slim Ceiling Mounted Duct Type
FXDQ-PBVE
20PB25PB32PB---------
FXDQ-PBVET
20PB25PB32PB---------
FXDQ-NBVE
---
40NB 50NB 63NB
------
FXDQ-NBVET
---
40NB 50NB 63NB
------
Ceiling Mounted Duct Type (Middle and High Static Pressure) FXMQ 20P 25P 32P 40P 50P 63P 80P 100P 125P 140P - - Ceiling Mounted Duct Type FXMQ ----------
200MA 250MA
Ceiling Suspended Type FXHQ - -
32MA
--
63MA
-
100MA
----
Wall Mounted Type FXAQ
20MA 25MA 32MA 40MA 50MA 63MA
------
Floor Standing Type FXLQ
20MA 25MA 32MA 40MA 50MA 63MA
------
Concealed Floor Standing Type FXNQ
20MA 25MA 32MA 40MA 50MA 63MA
------
Ceiling Suspended Cassette Type FXUQ ------
71MA
100MA 125MA
--- V1
Connection Unit BEVQ ------
71MA
100MA 125MA
--- VE
Type Model Name Symbol
Heat Pump Heat Recovery RWEYQ
8P 10P 16P 18P 20P Y1 24P 26P 28P 30P - - 10P - - 20P YL, TL ---30P-

Symptom-based Troubleshooting
12
1. Symptom-based
Troubleshooting
Symptom Supposed Cause Countermeasure
1 The system does not start
operation at all.
Blowout of
fuse(s)
Turn OFF the power
supply and then
replace the fuse(s).
Cutout of
breaker(s)
•
If the knob of any
breaker is in its
OFF position,
turn ON the
power supply.
•
If the knob of any
circuit breaker is
in its tripped
position, do not
turn ON the
power supply.
Power failure
After the power
failure is reset,
restart the system.
2 The system starts operation but
makes an immediate stop.
Blocked air inlet or outlet
of indoor or outdoor unit
Remove
obstacle(s).
Clogged air
filter(s)
Clean the air
filter(s).
3 The system does not cool or
heat air well.
Blocked air inlet or outlet
of indoor or outdoor unit
Remove
obstacle(s).
Clogged air filter(s) Clean the air filter(s).
Enclosed outdoor unit(s) Remove the enclosure.
Improper set
temperature
Set the temperature to
a proper degree.
Airflow rate set to
"LOW"
Set it to a proper
airflow rate.
Improper direction
of air diffusion
Set it to a proper
direction.
Open window(s) or door(s)
Shut it tightly.
[In cooling] Direct sunlight
received
Hang curtains or
shades on windows.
[In cooling]
Too many persons
staying in a room
The model must
be selected to
match the air
conditioning load.
[In cooling]
Too many heat sources
(e.g. OA equipment)
located in a room
ON
OFF
Knob
Tripped
Circuit breaker

Symptom-based Troubleshooting
13
4 The system
does not
operate.
The system stops
and immediately
restarts operation.
If the OPERATION
lamp on the remote
controller turns ON,
the system will be
normal. These
symptoms indicate
that the system is
controlled so as not to
put unreasonable
loads on the system.
Normal operation.
The system will
automatically
start operation
after a lapse of 5
minutes.
Pressing the
TEMP ADJUST
button immediately
resets the system.
The remote
controller displays
"UNDER
CENTRALIZED
CONTROL", which
blinks for a period of
several seconds
when the
OPERATION button
is depressed.
The system is
controlled with
centralized
controller. Blinking
display indicates that
the system cannot
be operated using
the remote
controller.
Operate the
system using the
COOL/HEAT
centralized
remote controller.
The system stops
immediately after
turning ON the
power supply.
The system is in
preparation mode
of micro computer
operation.
Wait for a period
of approximately
1 minute.
5 The system
makes
intermittent
stops.
The remote
controller
displays error
codes "U4" and
"U5", and the
system stops but
restarts after a
lapse of several
minutes.
The system stops
due to an
interruption in
communication
between units
caused by electrical
noises coming from
equipment other
than air
conditioners.
Remove causes
of electrical
noises.
If these causes
are removed, the
system will
automatically
restart operation.
6 COOL-HEAT
selection is
disabled.
The remote
controller displays
"UNDER
CENTRALIZED
CONTROL".
This remote
controller has no
option to select
cooling operation.
Use a remote
controller with
option to select
cooling operation.
The remote
controller displays
"UNDER
CENTRALIZED
CONTROL", and
the COOL-HEAT
selection remote
controller is
provided.
COOL-HEAT
selection is made
using the COOL-
HEAT selection
remote controller.
Use the COOL-
HEAT selection
remote controller
to select cool or
heat.
Symptom Supposed Cause Countermeasure

Symptom-based Troubleshooting
14
7
The system
conducts fan
operation but
not cooling or
heating
operation.
This symptom
occurs
immediately after
turning ON the
power supply.
The system is in
preparation mode
of operation.
Wait for a period
of approximately
10 minutes.
8 The airflow
rate is not
reproduced
according to
the setting.
Even pressing the
AIRFLOW RATE
SET button
makes no
changes in the
airflow rate.
In heating operation,
when the room
temperature reaches
the set degree, the
outdoor unit will stop
while the indoor unit
is brought to fan LL
operation so that no
one gets cold air.
Furthermore, if fan
operation mode is
selected when other
indoor unit is in
heating operation,
the system will be
brought to fan LL
operation.
(The fan LL
operation is also
enabled while in oil
return mode in
cooling operation.)
Normal operation.
9 The airflow
direction is
not
reproduced
according to
the setting.
The airflow
direction is not
corresponding to
that displayed on
the remote
controller.
The flap does not
swing.
Automatic control Normal operation.
Symptom Supposed Cause Countermeasure

Symptom-based Troubleshooting
15
10 A white mist
comes out
from the
system.
<Indoor unit>
In cooling
operation, the
ambient humidity
is high.
(This indoor unit
is installed in a
place with much
oil or dust.)
Uneven
temperature
distribution due to
heavy stain of the
inside of the
indoor unit
Clean the inside
of the indoor unit.
<Indoor unit>
Immediately after
cooling operation
stopping, the
ambient
temperature and
humidity are low.
Hot gas
(refrigerant) flown
in the indoor unit
results to be
vapor from the
unit.
Normal operation.
<Indoor and
outdoor units>
After the
completion of
defrosting
operation, the
system is
switched to
heating
operation.
Defrosted
moisture turns to
be vapor and
comes out from
the units.
Normal operation.
Symptom Supposed Cause Countermeasure