Mitsubishi Electric Mr.Slim PEA-A12AA4 Operating manual

TECHNICAL & SERVICE MANUAL
CONTENTS
1. PART NAMES AND FUNCTIONS ········2
2. SPECIFICATIONS·································3
3. OUTLINES AND DIMENSIONS············8
4. WIRING DIAGRAM ·······························9
5.
REFRIGERANT SYSTEM DIAGRAM ·······10
6. HEATER CONTROL ···························11
7. TROUBLESHOOTING·························14
8. DISASSEMBLY PROCEDURE ···········25
INDOOR UNIT
CM
I
N
T
E
R
T
E
K
L
I
S
T
E
D
Indoor unit
[Model names]
PEA-A12AA4
PEA-A18AA4
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
Model name
indication
No.HWE0807B
REVISED EDITION-B
December 2010

2
1PART NAMES AND FUNCTIONS
Indoor Unit
PEA-A12AA4
PEA-A18AA4
Air outlet duct flange
Air outlet
Air inlet

3
2SPECIFICATIONS
BTU/h
kW
A
˚F(˚C)
Fan
in.WG(Pa)
kW
m3/min
CFM
L/S
mm
In.
kg
in.(mm)
A
Liquid in.(mm)
Gas in.(mm)
in.(mm)
dB<A>
Net weight
R410A
Motor output
Airflow rate(Low-Mid-High)
Airflow rate(Low-Mid-High)
Airflow rate(Low-Mid-High)
Motor type
External finish
Wiring
Capacity
Model Name
Power source
Remark
Document
Standard
attachment
Power input
Current
Type x Quantity
Airflow direction
Temperature set range Remote controller
Varistor
External static press
Driving mechanism
External dimension
Drain piping diameter
H x W x D
<Cooling> Indoor: 80˚FD.B. / 67˚FW.B. (26.7˚CD.B. / 19.4˚CW.B.) Outdoor:95˚FD.B. (35˚CD.B. )
Insulation material
Air filter
Refrigerant control device
Protection devices
Note
Pipe length: 24-9/16ft (7.5m) Height difference: 0ft (0m)
2.Power consumption. Run current at 0.060[in.WG] (15Pa) (external static pressure)
3.Cooling capacity value at 1:1system
Heating capacity value at 1:1system
<Heating> Indoor:70˚FD.B. (21.1˚CD.B.) Outdoor:47˚FD.B. / 43˚FW.B. (8.3˚CD.B. / 6.1˚CW.B.)
1.Cooling/Heating capacity indicates the maximum value at operation under the following condition.
Refrigerant
piping diameter R410A
Sound level (Low-Mid-High)
(measured in anechoic room)
Heat exchanger
Terminal block
Power outlet A
Accessory
Min.size of wire
Amperage of wire breaker
Cooling
12000
0.07
0.57
67 to 86 (19 to 30)
Heating
-
-
-
-
208/230V (60Hz)
-
Sirocco fan x 2
0.02-0.06-0.14-0.20 (5-15-35-50)
DC brushless motor
0.096
Direct-driven
7.0-9.0-11.0
247-317-388
116-150-183
Galvanized
200 x 990 x 700
7-7/8 x 39 x 27-9/16
22
1/8 (1.6)
15
ø1/4 (ø6.35) Flare
ø1/2 (ø12.7) Flare
O.D. 1-1/4 (32)
23-28-33
Polystyrene foam, Polyethylene foam, Urethane foam
PP Honeycomb fabric (washable)
-
Fuse (250V 6.3A)
Cross fin (Aluminum fin and copper tube)
ERZV10D471
To outdoor unit : 3P To wired remote controller : 2P
10
Installation Manual, Instruction Book
Drain hose (flexible joint)
PEA-A12AA4
Cooling
18000
0.09
0.74
67 to 86 (19 to 30)
Heating
19000
0.07
0.63
63 to 83 (17 to 28)
208/230V (60Hz)
-
Sirocco fan x 4
0.02-0.06-0.14-0.20 (5-15-35-50)
DC brushless motor
0.096
Direct-driven
12.0-15.0-18.0
423-529-635
200-250-300
Galvanized
200 x 1190 x 700
7-7/8 x 46-7/8 x 27-9/16
28
1/8 (1.6)
15
ø1/4 (ø6.35) Flare
ø1/2 (ø12.7) Flare
O.D. 1-1/4 (32)
30-34-38
Polystyrene foam, Polyethylene foam, Urethane foam
PP Honeycomb fabric (washable)
-
Fuse (250V 6.3A)
Cross fin (Aluminum fin and copper tube)
ERZV10D471
To outdoor unit : 3P To wired remote controller : 2P
20
Installation Manual, Instruction Book
Drain hose (flexible joint)
PEA-A18AA4

4
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
PEA-A12AA4
External static pressure :
0.060[in.WG](15Pa)
High
Middle
33
SPL(dB)
28
Low 23
LINE
<60Hz>
NOTCH
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
PEA-A12AA4
External static pressure :
0.020[in.WG](5Pa)
High
Middle
33
SPL(dB)
28
Low 23
LINE
<60Hz>
NOTCH
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
PEA-A12AA4
External static pressure :
0.200[in.WG](50Pa)
High
Middle
35
SPL(dB)
31
Low 25
LINE
<60Hz>
NOTCH
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
PEA-A12AA4
External static pressure :
0.140[in.WG](35Pa)
High
Middle
34
SPL(dB)
29
Low 24
LINE
<60Hz>
NOTCH
NOTE: The sound level is measured in an anechoic room where echoes are few, when compressor stops. The sound
may be bigger than displayed level under actual installation condition by surrounding echoes. The sound level
can be higher by about 2 dB than the displayed level during cooling and heating operation.
SOUND CRITERION CURVES

5
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
PEA-A18AA4
External static pressure :
0.060[in.WG](15Pa)
High
Middle
38
SPL(dB)
34
Low 30
LINE
<60Hz>
NOTCH
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
PEA-A18AA4
External static pressure :
0.020[in.WG](5Pa)
High
Middle
37
SPL(dB)
33
Low 29
LINE
<60Hz>
NOTCH
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
PEA-A18AA4
External static pressure :
0.200[in.WG](50Pa)
High
Middle
39
SPL(dB)
36
Low 32
LINE
<60Hz>
NOTCH
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 μbar)
BAND CENTER FREQUENCIES, Hz
PEA-A18AA4
External static pressure :
0.140[in.WG](35Pa)
High
Middle
39
SPL(dB)
35
Low 31
LINE
<60Hz>
NOTCH
NOTE: The sound level is measured in an anechoic room where echoes are few, when compressor stops. The sound
may be bigger than displayed level under actual installation condition by surrounding echoes. The sound level
can be higher by about 2 dB than the displayed level during cooling and heating operation.

6
External static pressure [in.WG](Pa)
PEA-A12AA4
(External static pressure 0.060[in.WG](15Pa) 208/230V 60Hz
Airflow rate(m3/min)[CFM]
0
10
20
30
40
50
6789101112
[0.20]
[0.16]
[0.12]
[0.08]
[0.04]
[212] [247] [282] [318] [353] [388] [424]
Middle
Low
High
Limit
Rated point
0
40
30
20
10
[0.16]
[0.12]
[0.08]
[0.04]
External static pressure [in.WG](Pa)
6789101112
[212] [247] [282] [318] [353] [388] [424]
Airflow rate(m3/min)[CFM]
PEA-A12AA4
(External static pressure 0.020[in.WG](5Pa) 208/230V 60Hz
Middle
Low
High
Limit
Rated point
0
20
10
30
40
50
60
70
80
External static pressure [in.WG](Pa)
Airflow rate(m3/min)[CFM]
PEA-A12AA4
(External static pressure 0.200[in.WG](50Pa) 208/230V 60Hz
6789101112
[0.32]
[0.28]
[0.24]
[0.20]
[0.16]
[0.12]
[0.08]
[0.04]
[212] [247] [282] [318] [353] [388] [424]
Middle
Low
High
Limit
Rated point
0
20
10
30
40
50
60
70
80
External static pressure [in.WG](Pa)
PEA-A12AA4
(External static pressure 0.140[in.WG](35Pa) 208/230V 60Hz
6789101112
Airflow rate(m3/min)[CFM]
[0.32]
[0.28]
[0.24]
[0.20]
[0.16]
[0.12]
[0.08]
[0.04]
[212] [247] [282] [318] [353] [388] [424]
Middle
Low
High
Limit
Rated point
INDOOR FAN PERFORMANCE AND CORRECTED AIR FLOW

7
External static pressure [in.WG](Pa)
PEA-A18AA4
(External static pressure 0.060[in.WG](15Pa) 208/230V 60Hz
Airflow rate(m3/min)[CFM]
9 10111213141516171819
0
50
40
30
20
10
[0.20]
[0.16]
[0.12]
[0.08]
[0.04]
[318] [353] [388] [424] [494][459] [530] [565] [600] [671][636]
Middle
Low
High
Limit
Rated point
External static pressure [in.WG](Pa)
PEA-A18AA4
(External static pressure 0.020[in.WG](5Pa) 208/230V 60Hz
Airflow rate(m3/min)[CFM]
9 10111213141516171819
0
40
30
20
10 Middle
Low
High
Limit
Rated point
[0.16]
[0.12]
[0.08]
[0.04]
[318] [353] [388] [424] [494][459] [530] [565] [600] [671][636]
External static pressure [in.WG](Pa)
PEA-A18AA4
(External static pressure 0.200[in.WG](50Pa) 208/230V 60Hz
Airflow rate(m3/min)[CFM]
9 10111213141516171819
0
10
20
30
40
60
70
50
80
[0.32]
[0.28]
[0.24]
[0.20]
[0.16]
[0.12]
[0.08]
[0.04]
[318] [353] [388] [424] [494][459] [530] [565] [600] [671][636]
Middle
Limit
Rated point
Low
High
External static pressure [in.WG](Pa)
PEA-A18AA4
(External static pressure 0.140[in.WG](35Pa) 208/230V 60Hz
Airflow rate(m3/min)[CFM]
9 10111213141516171819
0
10
20
30
40
60
70
50
80
[0.32]
[0.28]
[0.24]
[0.20]
[0.16]
[0.12]
[0.08]
[0.04]
[318] [353] [388] [424] [494][459] [530] [565] [600] [671][636]
Middle
Limit
Rated point
Low
High

8
OUTLINES AND DIMENSIONS
3
Unit : mm(in.)
PEA-A12AA4
PEA-A18AA4
(46-7/8)
1190
(39)
990
N
(48-25/32)
1239
(40-29/32)
1039
M
ø12.7(1/2)
mm(in.)
(35-7/16)
(27-9/16)
(41-3/4)
(33-7/8)
(47-1/4)
(39-3/8)
(39-3/8)
(31-1/2)
(41-3/4)
(33-7/8)
(47-3/16)
(39-5/16)
(45-3/8)
(37-1/2)
(43-5/16)
(35-7/16)
ø6.35(1/4)
900 952 998 860 9800 1000 860 7700 20
24
L
900
K
9
J
1060
HG
1200
F
1000
E
11
D
1060
C
1100
B
1152
PEA-A12AA4
PEA-A18AA4
Model A
1198
Gas pipe Liquid pipe
12
Note1.Use M10 screw for the suspension bolt (field supply).
2.Keep the service space for the maintenance at the bottom.
3.This chart indicates for PEA-A12AA4 model,which has 2 fans.
PEA-A18AA4 models have 4 fans.
4.In case an inlet duct is used,remove the air filter(supply with
the unit), then install the filter(field supply) at suction side.
Drain pipe(O.D.ø32(1-1/4))
Terminal block (Remote controller transmission line)
Terminal block (Indoor/outdoor connecting line)
Refrigerant piping
flare connection (liquid)
Drain pipe(O.D.ø32(1-1/4))
(Emergency draining)
Knockout hole ø 27(1-3/32)
(Remote controller transmission line)
Knockout hole
ø 27(1-3/32)
(Indoor/outdoor connecting line)
L-ø2.9(1/8)
2X2-ø2.9(1/8)
2XE-ø2.9(1/8)
Control box
Air filter
Suspension bolt hole
4-14X30(9/16X1-3/16) Slot
Refrigerant piping
flare connection (gas)
Drain pipe(O.D.ø32(1-1/4))
(Spontaneous draining)
Air
inlet
Air
outlet
N
M
57(2-1/4)
57(2-1/4)
159(6-9/32)
345(13-19/32)
(3-9/16)
(5-29/32)
(2-25/32)(4-19/32)
70
10 (13/32)
(3-15/16)
(1-15/16) (24-5/8)
37(1-15/32)
200(7-7/8)
H
20(13/16)
157.5 (6-7/32)
20 (13/16)
100 (3-15/16)
37(1-15/32)
12(1/2)
12(1/2)
88(3-15/32)
100(3-15/16)XJ=K
100(3-15/16)
88(3-15/32)
10 (13/32)
49
25(1)
170(6-23/32)
102(4-1/32)
270(10-21/32)
116
150(Duct)
23(29/32)
100 25(1)
700(27-9/16)
677(26-21/32)
23 (29/32)
C
B (Suspension bolt pitch)23(29/32)
A
90
625 (Suspension bolt pitch)
D (Duct)
30(1-3/16) 100(3-15/16)X(E-1)=F
100(3-15/16)
20(13/16)
15(19/32)
(1-31/32 ~ 5-29/32)
(30-19/32)
(17-23/32)
(11-13/16)
(17-23/32)
More than 300
450
777
50(1-31/32)
50 ~ 150
50(1-31/32)
G450
Note2
Access door
Required space for service and maintenance
More than 20
More than 10
(13/16)
(13/32)
Access door
Ceiling surface
Make the access door at the appointed position
properly for service maintenance.
175±5(6-29/32±7/32)
Less than 300
Less than 550
(11-13/16)
(21-21/32)
Drain hose (I.D.ø32(1-1/4))
<accessory>
(Actual length)
2
1

9
4WIRING DIAGRAM
PEA-A12AA4
PEA-A18AA4
12
1~
M
ON
OFF
SW6
DC294-340V
RECTIFY CIRCUIT
RU
SW1
BZ1
SW2
LED1
CN1
W.B.
RFI
R.B.
12
X1
FUSE
DRAINPUMP
135
(BLACK)
CN01
CNP
INSIDE SECTION OF CONTROL BOX
(BLUE)
CN22
31
1
LED1
CN3C
SW2SW1 CN32
CN30(GREEN)
(RED)
CN20
CN41
SWE
ON OFF
CN51
(BLUE)
1474
59
95
2
12
41
FS TH2 TH5 TH1
FAN MOTOR
TB15
12
(RED)
CN105
(RED)
CN4F
(WHITE)
CN90
(WHITE)
CN44
(WHITE)
CNMF
(WHITE)
12
CN2L
TB6
(BLUE)
LED3
3
LED2
I. B.
S1
TB4
S3
S2
1
1
1
19
TRANSMISSION
WIRES DC 12V
-
+
MS
3~
SW2
SWITCH (HEATING ON/OFF)
SWITCH (COOLING ON/OFF)
SW1
RECEIVING UNIT RU
LED (RUN INDICATOR) LED1
BUZZER BZ1
IR WIRELESS REMOTE CONTROLLER BOARD
COND./EVA. TEMP. THERMISTOR TH5
PIPE TEMP. THERMISTOR/LIQUID TH2
INTAKE AIR TEMP. THERMISTOR TH1
CONNECTOR (EMERGENCY OPERATION)
SWITCH (FOR CAPACITY CODE)
SWITCH (FOR MODE SELECTION)
SWITCH (FOR MODEL SELECTION)
SWE
CONNECTOR (REMOTE SWITCH)
CONNECTOR (LLC)
CONNECTOR (LOSSNAY)
CONNECTOR (BACK-UP HEATING)
NAME NAMESYMBOL SYMBOLSYMBOL
I.B. I.B.
W.B.
OPTIONAL PARTS
R.B.
CN32
CN30
INDOOR CONTROLLER BOARD INDOOR CONTROLLER BOARD
SW2
SW1
SW6
SYMBOL EXPLANATION
NAME
CN2L
CN24
CONNECTOR (HA TERMINAL-A)
CN51
CN90
CN105
CN41
CONNECTOR (CENTRALLY CONTROL)
CONNECTOR (WIRELESS)
CONNECTOR
(RADIO FREQUENCY INTERFACE)
FUSE AC250V 6.3A FUSE
X1
AUX. RELAY
TB15
FLOAT SWITCH
RADIO FREQUENCY INTERFACE FOR RF THERMOSTAT
FS
RFI
REMOTE CONTROLLER BOARD
POWER SUPPLY (I.B.)
TERMINAL BLOCK
(REMOTE CONTROLLER TRANSMISSION LINE)
TERMINAL BLOCK
(INDOOR/OUTDOOR CONNECTING LINE)
TERMINAL BLOCK
(REMOTE CONTROLLER TRANSMISSION LINE)
TRANSMISSION (INDOOR-OUTDOOR)
POWER SUPPLY (I.B.)
LED1
TB6
LED3
LED2
TB4
Note1. Since the outdoor side electric wiring may change be sure to check the outdoor unit electric wiring for servicing.
2. Indoor and outdoor connecting wires are made with polarities,make wiring matchingterminal numbers (S1,S2,S3).
3. Symbols used in wiring diagram above are as follows.
:CONNECTOR
:TERMINAL
(HEAVY DOTTED LINE):FIELD WIRING
(THIN DOTTED LINE):OPTIONAL PARTS
4. Use copper supply wire.
TO OUTDOOR
UNIT
(YELLOW)
CN24
TB15 TB4
PARTS LOCATION
I . B.
CONTROL BOX

10
REFRIGERANT SYSTEM DIAGRAM
5
Pipe temperature
thermistor/liquid
(TH2)
Distributor
Condenser/evaporator
temperature thermistor
(TH5)
Room temperature
thermistor (TH1)
Refrigerant flow in cooling
Refrigerant flow in heating
Strainer
#50
Strainer
#50
Heat exchanger
Refrigerant GAS pipe connection
(Flare)
Refrigerant LIQUID pipe connection
(Flare)
PEA-A12AA4
PEA-A18AA4

11
6HEATER CONTROL
6-1. Control specifications and Function setting
Table 1 shows how the field-installed heater is controlled. Select the desired pattern in the table below, and set the
Function on the indoor units as shown in Table 1.
Table.1 [Function table]
Select unit numbers 01 to 03 or all units (AL[wired remote controller] / 07[IR wireless remote controller])
*Refer to the Installation Manual for function settings.
Mode Setting Mode no. Setting
Initial setting
Heater control
23 1
23 2 -
Heater OFF
Inlet air temp. set temp.
Heater ON
Inlet air temp. < set temp.-4.5˚F(2.5˚C)
The fan will stop and the heater will turn off when
[DEFROST] or [ERROR] is displayed.
The fan will drive and the heater will turn on when
[DEFROST] or [ERROR] is displayed.
Set temp.
Set temp.-1.8
˚ F(1 ˚C )
Set tem p.-4.5
˚ F(2.5 ˚C )
Inlet air temp.
Heater output OFF
ON
Heater OFF
Inlet air temp. set temp.
Heater ON
Inlet air temp. < set temp.-1.8˚F(2.5˚C)
Set temp.
Set temp.-1.8
˚ F(2.5 ˚C )
Inlet air temp.
Heater output OFF
ON
6-2. Fan control
*Refer to the Installation Manual for function settings.
By setting the Mode No. 23 in the Function Table in section 6-1 to 2 and using CN4Y on the optional parts PAC-YU25HT, the
following patterns of fan control will become possible when [DEFROST] or [ERROR] is displayed.
Fan control patterns when [DEFROST] or [ERROR] is displayed
*1 Fan speed setting
* If a heater is installed in the duct, do not use CN4Y. By doing so, the fan will turn off when the heater is on,
which may result in fire.
Heater is installed in the duct. No heater is installed in the duct.
Use of CN4Y (PAC-YU25HT)
Heater is off.
Heater is on.
Unused*
Fan ON*1
Fan ON*1
Fan OFF
Fan OFF
Used
Setting Mode no. Setting
Mode
Fan control
Very low
Heating Thermo-OFF [DEFROST] or [ERROR]
STOP
Remote controller setting
Remote controller setting
Remote controller setting
Very low 25
25
25
1
2
3
Initial setting
-
-

12
The following section describes installation of the External Heater Adapter that connects to PEA-A AA4
series indoor unit. This products is the special wiring parts to drive an electric heater with the air conditioner.
(1) Parts list
Check that the following parts are included in the package.
1) External output cable (with a yellow connector).............................2 in total
Two types of cables with different connectors are included.
2) Panel heater connector.................................................................. 3 in total
White: 1
Green: 2 (2 types)
(2) Connection to the indoor unit
Use the cables that fit the connectors on the indoor unit control board.
1) External output cable (with a yellow connector)
This cable is used to connect a relay circuit for an interlocked operation with either an electric or a panel heater.
Connect the cable to CN24 on the indoor unit control board.
2) Panel heater connector (with a white connector)
This connector is used to perform an interlocked operation with a panel heater. Depending on the indoor unit
control board specification, connect the cable to CN4Y as appropriate
CN4Y for FAN control
(PAC-YU25HT)
<Image>
6-3. PAC-YU25HT (Optional Parts) installation
(3) Locally procured wiring
A basic connection method is shown below.
CN24
X
X
Remote control board Relay circuit Adapter
Indoor unit
control board
Electric Heater power source
Electric Heater
or panel
heater
Red 1
White 2
Preparations in the field Maximum cable length
is 10 m (32ft)
YellowWhite
White 1
(applicable only when a panel
heater is connected)
3
CN4Y

13
For relay X use the specifications given below Operation coil
Rated voltage: 12VDC
Power consumption: 0.9W or less
* Use the diode that is recommended by the relay manufacturer at both ends of the relay coil.
The length of the electrical wiring for the PAC-YU25HT is 2 meters (6-1/2 ft.)
To extend this length, use sheathed 2-core cable.
Control cable type: CVV, CVS, CPEV or equivalent.
Cable size: 0.5 mm2~ 1.25 mm2(16 to 22 AWG)
Don't extend the cable more than 10 meters (32ft)
(4) Wiring restrictions
Keep the length of the cable connecting to the circuit board of the indoor unit shorter than 10 meters (32ft).
Longer than 10 meters (32ft) could cause improper operation.
Use a transit relay when extending wiring such as remote wiring.
Recommended circuit
Wiring diagram
1-phase
power supply
208V, 230V/60Hz
Control board
FS1, 2 ----- Thermal fuse
H1, H2 ----- Heater
26H --------- Overheat
protection thermostat
88H --------- Electromagnetic contactor
FS1
FS2
FS1
FS2
R
S
R
S
CN24
H2
88H
H1
88H
26H
88H

14
7TROUBLESHOOTING
7-1. CAUTIONS ON TROUBLESHOOTING
(1) Before troubleshooting, check the followings:
1Check the power supply voltage.
2Check the indoor/outdoor connecting wire for mis-wiring.
(2) Take care the followings during servicing.
1Before servicing the air conditioner, be sure to turn off the remote controller first to stop the main unit, and then turn
off the breaker.
2When removing the indoor controller board, hold the edge of the board with care NOT to apply stress on the
components.
3When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
Lead wires

15
7-2. SELF-CHECK FUNCTION
• Refer to the installation manual that comes with each remote controller for details.
• RF thermostat is not established.
• If the unit cannot be operated properly after the above test run has been performed, refer to the following table to remove the cause.
On the IR wireless remote controller with conditions above, following phenomena takes place.
• No signals from the remote controller are accepted.
• OPE lamp is blinking.
• The buzzer makes a short ping sound.
Note:
Operation is not possible for about 30 seconds after cancellation of function selection. (Correct operation)
PLEASE WAIT
PLEASE WAIT →Error code
Display messages do not appear
even when operation switch is
turned ON (operation lamp does
not light up).
Symptom
After LED 1, 2 are lighted, LED 2 is turned
off, then only LED 1 is lighted. (Correct
operation)
Only LED 1 is lighted. →LED 1, 2 blink.
Only LED 1 is lighted. →LED 1, 2 blinks
twice, LED 2 blinks once.
• For about 2 minutes after power-on, operation of the
remote controller is not possible due to system start-up.
(Correct operation)
• Connector for the outdoor unit’s protection device is not
connected.
• Reverse or open phase wiring for the outdoor unit’s power
terminal block (L1, L2, L3)
• Incorrect wiring between indoor and outdoor units
(incorrect polarity of S1, S2, S3)
• Remote controller wire short
For about 2 minutes
following power-on
After about 2 min-
utes has expired
following power-on
LED 1, 2 (PCB in outdoor unit)Wired remote controller Cause
[Output pattern B] Errors detected by unit other than indoor unit (outdoor unit, etc.)
Indoor/outdoor unit communication error (Transmitting error) (Outdoor unit)
Compressor overcurrent interruption
Open/short of outdoor unit thermistors
Compressor overcurrent interruption (When compressor locked)
Abnormal high discharging temperature/49C worked/ insufficient refrigerant
Abnormal high pressure (63H worked)/ Overheating safeguard operation
Abnormal temperature of heat sink
Outdoor unit fan protection stop
Compressor overcurrent interruption/Abnormal of power module
Abnormality of super heat due to low discharge temperature
Abnormality such as overvoltage or voltage shortage and abnormal
synchronous signal to main circuit/Current sensor error
–
–
Other errors (Refer to the technical manual for the outdoor unit.)
For details, check the LED
display of the outdoor controller
board.
[Output pattern A] Errors detected by indoor unit
IR wireless remote controller
Beeper sounds/OPERATION
INDICATOR lamp flashes
(Number of times)
1
2
3
4
5
6
7
8
9
10
11
12
No sound
Wired remote controller
RF thermostat
Check code
P1
P2, P9
E6, E7
P4
P5
P6
EE
P8
E4
–
–
Fb
– –
IR wireless remote controller
Beeper sounds/OPERATION
INDICATOR lamp flashes
(Number of times)
1
2
3
4
5
6
7
8
9
10
11
12
Wired remote controller
RF thermostat
Check code
E9
UP
U3, U4
UF
U2
U1, Ud
U5
U8
U6
U7
U9, UH
–
13
14
–
Others
Symptom
Intake sensor error
Pipe (Liquid or 2-phase pipe) sensor error
Indoor/outdoor unit communication error
Drain sensor error
Drain pump error
Freezing/Overheating safeguard operation
Communication error between indoor and outdoor units
Pipe temperature error
Remote controller signal receiving error
–
–
Indoor unit control system error (memory error, etc.)
No corresponding
Remark
*1 If the beeper does not sound again after the initial two beeps to confirm the self-check start signal was received and the OPERATION INDICATOR lamp does not
come on, there are no error records.
*2 If the beeper sounds three times continuously “beep, beep, beep (0.4 + 0.4 + 0.4 sec.)” after the initial two beeps to confirm the self-check start signal was
received, the specified refrigerant address is incorrect.
• On IR wireless remote controller
The continuous buzzer sounds from receiving section of indoor unit.
Blink of operation lamp
• On wired remote controller
Check code displayed on the LCD.
Symptom Remark

16
Indicates whether control power is supplied. Make sure that this LED is always lit.
Indicates whether power is supplied to the remote controller. This LED lights only in the case of
the indoor unit which is connected to the outdoor unit refrigerant address “0”.
Indicates state of communication between the indoor and outdoor units. Make sure that this LED is
always blinking.
LED 1 (power for microcomputer)
LED 2 (power for remote controller)
LED 3 (communication between indoor and outdoor units)
AUTO RESTART FUNCTION
Indoor controller board
This model is equipped with the AUTO RESTART FUNCTION.
When the indoor unit is controlled with the remote controller, the operation mode, set temperature, and the fan speed are memorized by the indoor controller board.
The auto restart function sets to work the moment the power has restored after power failure, then, the unit will restart automatically.
Set the AUTO RESTART FUNCTION using the wireless remote controller. (Mode no.1).
For description of each LED (LED1, 2, 3) provided on the indoor controller, refer to the following table.

17
7-3. SELF-DIAGNOSIS ACTION TABLE Note: Refer to the manual of outdoor unit for the details of display
such as F, U, and other E.
Error Code Abnormal point and detection method Cause Countermeasure
P1
Room temperature
thermistor (TH1)
1The unit is in three-minute resume
prevention mode if short/open of
thermistor is detected. Abnormal if the
unit does not reset normally after three
minutes. (The unit returns to normal
operation, if it has normally reset.)
2Constantly detected during cooling,
drying and heating operation
Short: 90˚C[194˚F] or more
Open: -40˚C[-40˚F] or less
1Defective thermistor
characteristics
2Contact failure of connector
(CN20) on the indoor controller
board (Insert failure)
3Breaking of wire or contact
failure of thermistor wiring
4Defective indoor controller
board
1–3Check resistance value of thermistor.
0:[32˚F].......15.0k"
10:[50˚F].....9.6k"
20:[68˚F].....6.3k"
30:[86˚F].....4.3k"
40:[104˚F]...3.0k"
If you put force on (draw or bend) the lead wire
with measuring resistance value of thermistor
breaking of wire or contact failure can be
detected.
2Check contact failure of connector (CN20) on
the indoor controller board. Refer to 7-5.
Turn the power on again and check restart
after inserting connector again.
4Check room temperature display on remote
controller.
Replace indoor controller board if there is
abnormal difference with actual room
temperature.
Turn the power off, and on again to operate
after check.
P2
Pipe temperature
thermistor/Liquid (TH2)
1The unit is in three-minute resume
prevention mode if short/open of
thermistor is detected. Abnormal if the
unit does not reset normally after three
minutes. (The unit returns to normal
operation, if it has normally reset.)
2Constantly detected during cooling,
drying, and heating (except defrosting)
operation.
Short: 90˚C[194˚F] or more
Open: -40˚C[-40˚F] or less
1Defective thermistor
characteristics
2Contact failure of connector
(CN44) on the indoor controller
board (Insert failure)
3Breaking of wire or contact
failure of thermistor wiring
4Defective refrigerant circuit is
causing thermistor temperature
of 90˚C[194˚F] or more or
-40˚C[-40˚F] or less.
5Defective indoor controller board
1–3Check resistance value of thermistor.
For characteristics, refer to (P1) above.
2Check contact failure of connector (CN44) on
the indoor controller board. Refer to 7-5. Turn
the power on again and check restart after
inserting connector again.
4Check pipe <liquid> temperature with remote
controller in test run mode. If pipe <liquid>
temperature is extremely low (in cooling
mode) or high (in heating mode), refrigerant
circuit may have defective.
5Check pipe <liquid> temperature with remote
controller in test run mode. If there is extreme
difference with actual pipe <liquid> temperature,
replace indoor controller board.
Turn the power off, and on again to operate
after check.
P4
(5701)
Contact failure of drain float switch (CN4F)
1Extract when the connector of drain float
switch is disconnected.
(3and 4of connector CN4F is not
short-circuited.)
2Constantly detected during operation.
1Contact failure of connector
(Insert failure)
2Defective indoor controller
board
1Check contact failure of float switch connec-
tor.
Turn the power on again and check after
inserting connector again.
2Operate with connector (CN4F) short-circuited.
Replace indoor controller board if abnormali-
ty reappears.
P5
Drain overflow protection operation
1Suspensive abnormality, if drain float
switch is detected to be underwater for 1
minute and 30 seconds continuously
with drain pump on.
Turn off compressor and indoor fan.
2Drain pump is abnormal if the condition
above is detected during suspensive
abnormality.
3Constantly detected during drain pump
operation.
1Malfunction of drain pump
2Defective drain
Clogged drain pump
Clogged drain pipe
3Defective drain float switch
Catch of drain float switch or
malfunction of moving parts
cause drain float switch to be
detected under water (Switch
On)
4Defective indoor-controller
board
1Check if drain-up machine works.
2Check drain function.
3Remove drain float switch connector CN4F
and check if it is short (Switch On) with the
moving part of float switch UP, or OPEN with
the moving part of float switch down.
Replace float switch if it is short with the
moving part of float switch down.
4Replace indoor controller board if it is short-
circuited between 3-4of the drain float
switch connector CN4F and abnormality
reappears.
It is not abnormal if there is no problem about
the above-mentioned 1~4
Turn the power off, and on again to operate
after check.

18
Error Code Abnormal point and detection method Cause Countermeasure
P6
Freezing/overheating protection is
working
1Freezing protection (Cooling mode)
The unit is in six-minute resume prevention
mode if pipe <liquid or condenser/evap-
orator> temperature stays under
-15˚C[5˚F] for three minutes after the
compressor started. Abnormal if it stays
under -15˚C[5˚F] for three minutes again
within 16 minutes after six-minute
resume prevention mode.
2Overheating protection (Heating mode)
The units is in six-minute resume
prevention mode if pipe <Liquid or con-
denser / evaporator> temperature is
detected as over 70˚C[158˚F] after the
compressor started. Abnormal if the
temperature of over 70˚C[158˚F] is
detected again within 10 minutes after
six-minute resume prevention mode.
P8
1Slight temperature difference
between indoor room
temperature and pipe <liquid
or condenser / evaporator>
temperature thermistor
• Shortage of refrigerant
• Disconnected holder of pipe
<liquid or condenser /
evaporator> thermistor
• Defective refrigerant circuit
2Converse connection of
extension pipe (on plural units
connection)
3Converse wiring of indoor/
outdoor unit connecting wire
(on plural units connection)
4Defective detection of indoor
room temperature and pipe
<condenser / evaporator>
temperature thermistor
5Stop valve is not opened
completely.
(Cooling or drying mode)
1Clogged filter (reduced airflow)
2Short cycle of air path
3Low-load (low temperature)
operation beyond the tolerance
range
4Defective indoor fan motor
• Fan motor is defective.
• Indoor controller board is
defective.
5Defective outdoor fan control
6Overcharge of refrigerant
7Defective refrigerant circuit
(clogs)
(Heating mode)
1Clogged filter (reduced airflow)
2Short cycle of air path
3Over-load (high temperature)
operation beyond the tolerance
range
4Defective indoor fan motor
• Fan motor is defective.
• Indoor controller board is
defective.
5Defective outdoor fan control
6Overcharge of refrigerant
7Defective refrigerant circuit
(clogs)
8Bypass circuit of outdoor unit
is defective.
(Cooling or drying mode)
1Check clogging of the filter.
2Remove shields.
4Refer to 7-7. DC Fan motor (FAN MOTOR/
INDOOR CONTROLLER BOARD)
5Check outdoor fan motor.
67 Check operating condition of refrigerant
circuit.
(Heating mode)
1Check clogs of the filter.
2Remove shields.
4Refer to 7-7. DC Fan motor (FAN MOTOR/
INDOOR CONTROLLER BOARD)
5Check outdoor fan motor.
6~8Check operating condition of refrigerant
circuit.
Pipe temperature
<Cooling mode>
Detected as abnormal when the pipe tem-
perature is not in the cooling range 3 min-
utes after compressor start and 6 minutes
after the liquid or condenser/evaporator pipe
is out of cooling range.
Note 1) It takes at least 9 minutes. to
detect.
Note 2) Abnormality P8 is not detected in
drying mode.
Cooling range :
-3 deg˚C(-5.4deg˚F) ] (TH-TH1)
TH: Lower temperature between: liquid
pipe temperature (TH2) and con-
denser/evaporator temperature (TH5)
TH1: Intake temperature
<Heating mode>
When 10 seconds have passed after the
compressor starts operation and the hot
adjustment mode has finished, the unit is
detected as abnormal when
condenser/evaporator pipe temperature is
not in heating range within 20 minutes.
Note 3) It takes at least 27 minutes to
detect abnormality.
Note 4) It excludes the period of defrosting
(Detection restarts when defrost-
ing mode is over)
Heating range :
3 deg˚C(5.4deg˚F) [ (TH5-TH1)
1~4Check pipe <liquid or condenser /
evaporator> temperature with room
temperature display on remote
controller and outdoor controller circuit
board.
Pipe <liquid or condenser / evaporator>
temperature display is indicated by
setting SW2 of outdoor controller circuit
board as follows.
23Check converse connection of extension
pipe or converse wiring of indoor/outdoor
unit connecting wire.
Conduct temperature check with outdoor
controller circuit board after connecting
‘A-Control Service Tool(PAC-SK52ST)’.
()

19
Error Code Abnormal point and detection method Cause Countermeasure
P9
Abnormality of pipe temperature ther-
mistor / Condenser-Evaporator (TH5)
1The unit is in three-minute resume pro-
tection mode if short/open of thermistor
is detected. Abnormal if the unit does
not get back to normal within three min-
utes. (The unit returns to normal opera-
tion, if it has normally reset.)
2Constantly detected during cooling, dry-
ing, and heating operation (except
defrosting)
Short: 90˚C[194˚F] or more
Open: -40˚C[-40˚F] or less
1Defective thermistor
characteristics
2Contact failure of connector
(CN44) on the indoor controller
board (Insert failure)
3Breaking of wire or contact
failure of thermistor wiring
4Temperature of thermistor is
90˚C[194˚F] or more or
-40˚C[-40˚F] or less caused by
defective refrigerant circuit.
5Defective indoor controller
board
1–3Check resistance value of thermistor.
For characteristics, refer to (P1) above.
2Check contact failure of connector (CN44)
on the indoor controller board.
Refer to 7-5.
Turn the power on and check restart after
inserting connector again.
4Operate in test run mode and check pipe
<condenser / evaporator> temperature.
If pipe <condenser / evaporator> tempera-
ture is extremely low (in cooling mode) or
high (in heating mode), refrigerant circuit
may have defect.
5When no problems are found in 1-4above,
replace the indoor unit control board.
E0
or
E4
Remote controller transmission
error(E0)/signal receiving error(E4)
1Abnormal if main or sub remote con-
troller can not receive normally any
transmission from indoor unit of refriger-
ant address “0” for three minutes.
(Error code : E0)
2Abnormal if sub remote controller could
not receive for any signal for two min-
utes. (Error code: E0)
1Abnormal if indoor controller board can
not receive normally any data from
remote controller board or from other
indoor controller board for three minutes.
(Error code: E4)
2Indoor controller board cannot receive
any signal from remote controller for two
minutes. (Error code: E4)
1Check disconnection or looseness of indoor
unit or transmission wire of remote controller.
2Set one of the remote controllers “main”.
If there is no problem with the action above.
3Check wiring of remote controller.
• Total wiring length: max.500m
(Do not use cable ✕3 or more)
• The number of connecting indoor units:
max.16units
• The number of connecting remote con-
troller: max.2units
When it is not the above-mentioned problem of
1~3
4Diagnose remote controllers.
a) When “RC OK” is displayed,
Remote controllers have no problem.
Turn the power off, and on again to check.
If abnormality generates again, replace
indoor controller board.
b) When “RC NG” is displayed,
Replace remote controller.
c) When “RC E3” is displayed,
d) When “ERC 00-06” is displayed,
[ c),d)→Noise may be causing abnormality. ]
∗If the unit is not normal after replacing
indoor controller board in group control,
indoor controller board of address “0”
may be abnormal.
E3
or
E5
Remote controller transmission
error(E3)/signal receiving error(E5)
1Abnormal if remote controller could not
find blank of transmission path for six
seconds and could not transmit.
(Error code: E3)
2Remote controller receives transmitted
data at the same time, compares the
data, and when detecting it, judges
different data to be abnormal 30
continuous times. (Error code: E3)
1Abnormal if indoor controller board could
not find blank of transmission path.
(Error code: E5)
2Indoor controller board receives trans-
mitted data at the same time, compares
the data,and when detecting it, judges
different data to be abnormal 30
continuous times. (Error code: E5)
1Set a remote controller to main, and the
other to sub.
2Remote controller is connected with only one
indoor unit.
3The address changes to a separate setting.
4~6 Diagnose remote controller.
a) When “RC OK”is displayed, remote con-
trollers have no problem.
Turn the power off,and on again to check.
When becoming abnormal again, replace
indoor controller board.
b)When “RC NG”is displayed, replace
remote controller.
c)When “RC E3”or “ERC 00-66”is displayed,
noise may be causing abnormality.
1Contact failure at transmission
wire of remote controller
2All remote controllers are set
as “sub” remote controller. In
this case, E0 is displayed on
remote controller, and E4 is
displayed at LED (LED1, LED2)
on the outdoor controller circuit
board.
3Mis-wiring of remote controller
4Defective transmitting receiving
circuit of remote controller
5Defective transmitting receiving
circuit of indoor controller board
of refrigerant address “0”
6Noise has entered into the
transmission wire of remote
controller.
1Two remote controller are set
as “main.”
(In case of 2 remote con-
trollers)
2Remote controller is connected
with two indoor units or more.
3Repetition of refrigerant
address
4Defective transmitting receiving
circuit of remote controller
5Defective transmitting receiving
circuit of indoor controller
board
6Noise has entered into trans-
mission wire of remote con-
troller.

20
E6
1Contact failure, short circuit or,
mis-wiring (converse wiring) of
indoor/outdoor unit connecting
wire
2Defective transmitting receiving
circuit of indoor controller board
3Defective transmitting receiving
circuit of indoor controller board
4Noise has entered into indoor/
outdoor unit connecting wire.
∗Check LED display on the outdoor control cir-
cuit board. (Connect A-control service tool,
PAC-SK52ST.)
Refer to EA-EC item if LED displays EA-EC.
1Check disconnection or looseness of indoor/
outdoor unit connecting wire of indoor unit or
outdoor unit.
Check all the units in case of twin triple
indoor unit system.
2-4Turn the power off, and on again to check.
If abnormality generates again, replace
indoor controller board or outdoor
controller circuit board.
∗Other indoor controller board may have
defect in case of twin triple indoor unit
system.
E7
Indoor/outdoor unit communication
error (Transmitting error)
Abnormal if “1” receiving is detected 30
times continuously though indoor controller
board has transmitted “0”.
1Defective transmitting receiving
circuit of indoor controller board
2Noise has entered into power
supply.
3Noise has entered into outdoor
control wire.
1-3Turn the power off, and on again to check.
If abnormality generates again, replace
indoor controller board.
Indoor/outdoor unit communication
error (Signal receiving error)
1Abnormal if indoor controller board
cannot receive any signal normally for
six minutes after turning the power on.
2Abnormal if indoor controller board
cannot receive any signal normally for
three minutes.
3Consider the unit as abnormal under the
following condition: When two or more
indoor units are connected to an
outdoor unit, indoor controller board
cannot receive a signal for three minutes
from outdoor controller circuit board, a
signal which allows outdoor controller
circuit board to transmit signals.
Error Code Abnormal point and detection method Cause Countermeasure
Fb
Indoor controller board
Abnormal if data cannot be read normally
from the nonvolatile memory of the indoor
controller board.
1Defective indoor controller
board
1Replace indoor controller board.
E1
or
E2
Remote controller control board
1Abnormal if data cannot be read normal-
ly from the nonvolatile memory of the
remote controller control board.
(Error code: E1)
2Abnormal if the clock function of remote
controller cannot be operated normally.
(Error code: E2)
1Defective remote controller 1Replace remote controller.
PA
(2500)
Water leakage
This detection is performed during the
operation (stop, heating, fan, or error stop
mode etc.) other than cooling and dry.
1When a) and b) are found, water leakage
occurs.
a) Pipe <liquid> temperature - inlet tem-
perature < -10˚C[14˚F] for 30 minutes
b) When drain float switch is detected to
be soaked in the water for 15 minutes
or more.
* When drain float switch is detected to
be NOT soaked in the water, each
counting of a) and b) is cleared.
*When this error is detected, the error
will not be reset until the main power is
reset.
1Mis-piping of extension pipes
(When connected with multiple
units)
2Mis-wiring of indoor/outdoor
unit connecting wire (When
connected with multiple units)
3Detection failure of the indoor
unit inlet/ pipe <liquid> ther-
mistor
4Drain pump failure
5Drainage failure
· Clogged drain pump
· Clogged drain pipe
6Drain float switch failure
· Drain float switch is detected
to be soaked in the water (ON
status) due to the operation
failure of the moving parts.
· Contact failure of drain float
switch connector
(Loose connector)
1Check the extension pipes for mis-piping.
2Check the Indoor/outdoor unit connecting
wire for mis-wiring.
3Check room temperature display on remote
controller and indoor pipe <liquid> tempera-
ture. (Refer to the countermeasure on P2.)
4Check if drain-up machine works.
5Check drain function.
6Check drain float switch. (Refer to the coun-
termeasure on P4 and P5.)