Mitsubishi Electric Mr. Slim PLA-A12BA User manual

SERVICE MANUAL
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
SPLIT-TYPE, AIR CONDITIONERS
3 3 2 2 3
CONTENTS
1. TECHNICAL CHANGES.......................... 2
2. REFERENCE MANUAL........................... 2
3. SAFETY PRECAUTION........................ 3
4. PART NAMES AND FUNCTIONS ........ 5
5. SPECIFICATIONS................................. 8
6. NOISE CRITERION CURVES............. 10
7. OUTLINES AND DIMENSIONS............12
8.
WIRING DIAGRAM
................................ 13
9.
REFRIGERANT SYSTEM DIAGRAM
...... 15
10. TROUBLESHOOTING ........................ 16
11. SPECIAL FUNCTION.......................... 31
12. DISASSEMBLY PROCEDURE........... 34
NOTE:
• This manual describes only
service data of the indoor units.
• RoHS compliant products have
<G> mark on the spec name
plate.
PARTS CATALOG (OCB420)
WIRED REMOTE
CONTROLLER
WIRELESS REMOTE
CONTROLLER
ON/OFF TEMP
ON/OFF
TEMP.
INDOOR UNIT
Model name
indication
No. OCH420
REVISED EDITION-A
October 2007
PLA-A12BA PLA-A12BA1
PLA-A18BA PLA-A18BA1
PLA-A24BA PLA-A24BA1
PLA-A30BA PLA-A30BA1
PLA-A36BA PLA-A36BA1
PLA-A42BA PLA-A42BA1
PLA-A12BA
PLA-A18BA
PLA-A24BA
PLA-A30BA
PLA-A36BA
PLA-A42BA
Revision:
• PLA-A12/18/24/30/36/42BA1
are added in REVISED
EDITION-A.
• Some descriptions have been
modified.
•Please void OCH420.
Indoor unit
[Model names] [Service Ref.]

2
2REFERENCE MANUAL
Service Ref.
PUZ-A18/24/30/36/42NHA
PUZ-A18/24/30/36/42NHA-BS
PUY-A12/18/24/30/36/42NHA
(1)
PUY-A12/18/24/30/36/42NHA
(1)
-BS
Service Manual No.
OC367
PUZ-HA36NHA
OCH426
OCB426
2-1. OUTDOOR UNIT SERVICE MANUAL
Series (Outdoor unit)
PUZ-A·NHA(-BS)
PUY-A·NHA(-BS)
Data Book No.
OCS04
2-2. TECHNICAL DATA BOOK
1TECHNICAL CHANGES
PLA-A12BA PLA-A12BA1
PLA-A18BA PLA-A18BA1
PLA-A24BA PLA-A24BA1
PLA-A30BA PLA-A30BA1
PLA-A36BA PLA-A36BA1
PLA-A42BA PLA-A42BA1
INDOOR CONTROLLER BOARD(I.B) has been changed(11. SPECIAL FUNCTION is added).

3
SAFETY PRECAUTION
3
Cautions for units utilising refrigerant R410A
3-2. CAUTIONS RELATED TO NEW REFRIGERANT
Use new refrigerant pipes.
Make sure that the inside and outside of refrige-
rant piping is clean and it has no contamination
such as sulfur hazardous for use, oxides, dirt,
shaving particles, etc.
In addition, use pipes with specified thickness.
Store the piping to be used during installation
indoors and keep both ends of the piping sealed
until just before brazing. (Leave elbow joints, etc.
in their packaging.)
Use ester oil, ether oil or alkylbenzene oil (small
amount) as the refrigerant oil applied to flares
and flange connections.
Charge refrigerant from liquid phase of gas
cylinder.
If the refrigerant is charged from gas phase, composition
change may occur in refrigerant and the efficiency will be
lowered.
Do not use refrigerant other than R410A.
If other refrigerant (R22 etc.) is used, chlorine in refrige-
rant can cause deterioration of refrigerant oil etc.
Use a vacuum pump with a reverse flow check
valve.
Vacuum pump oil may flow back into refrigerant cycle and
that can cause deterioration of refrigerant oil etc.
Use the following tools specifically designed for
use with R410A refrigerant.
The following tools are necessary to use R410A refrigerant.
Keep the tools with care.
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
Do not use a charging cylinder.
If a charging cylinder is used, the composition of refrigera-
nt will change and the efficiency will be lowered.
Flare tool
Electronic refrigerant
charging scale
Vacuum pump adaptor
Size adjustment gauge
Gauge manifold
Torque wrench
Gas leak detector
Charge hose
Tools for R410A
Contamination inside refrigerant piping can cause deterio-
ration of refrigerant oil etc.
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
If large amount of mineral oil enters, that can cause deterio-
ration of refrigerant oil etc.
Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.
[1] Cautions for service
(1) Perform service after recovering the refrigerant left in the unit completely.
(2) Do not release refrigerant in the air.
(3) After completing service, charge the cycle with specified amount of refrigerant.
(4) When performing service, install a filter drier simultaneously.
Be sure to use a filter drier for new refrigerant.
3-1. ALWAYS OBSERVE FOR SAFTY
Before obtaining access to terminal, all supply
circuits must be disconnected.

4
Gravimeter
Unit
[3] Service tools
Use the below service tools as exclusive tools for R410A refrigerant.
No. Tool name Specifications
Gauge manifold ·Only for R410A
·Use the existing fitting specifications. (UNF1/2)
·Use high-tension side pressure of 5.3MPa·G or over.
Charge hose ·Only for R410A
·Use pressure performance of 5.09MPa·G or over.
Electronic scale
Gas leak detector ·Use the detector for R134a, R407C or R410A.
Adaptor for reverse flow check ·Attach on vacuum pump.
Refrigerant charge base
Refrigerant cylinder ·Only for R410A ·Top of cylinder (Pink)
·Cylinder with syphon
Refrigerant recovery equipment
[2] Additional refrigerant charge
When charging directly from cylinder
· Check that cylinder for R410A on the market is syphon type.
· Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.)

5
4PART NAMES AND FUNCTIONS
Drain pipe
Filter
Vane
Gas pipe
Liquid pipe
Air outlet
i-see sensor
(option)
Air intake
(Intake grille)

6
°F°C
°F°C
ERROR CODE
AFTER
TIMER
TIME SUN MON TUE WED THU FRI SAT
ON
OFF
Hr
AFTER
FILTER
FUNCTION
ONLY1Hr.
WEEKLY
SIMPLE
AUTO OFF
PAR-21MAA
ON/OFF
FILTER
CHECK
OPERATION
CLEAR
TEST
TEMP.
MENU
BACK DAY
MONITOR/SET
CLOCK
ON/OFF
•
•
Display Section
For purposes of this explanation,
all parts of the display are shown
as lit. During actual operation, only
the relevant items will be lit.
Identifies the current operation
Shows the operating mode, etc.
*Multilanguage display is available.
“Centrally Controlled” indicator
Indicates that operation from the
remote controller has been prohib-
ited by a master controller.
“Timer is Off” indicator
Indicates that the timer is off.
Temperature Setting
Shows the target temperature.
Day-of-Week
Shows the current day of the week.
Time/Timer Display
Shows the current time, unless the simple or Auto Off
timer is set.
If the simple or Auto Off timer is set, the time to be
switched off is shown.
“Sensor” indication
Displayed when the remote controller
sensor is used.
“Locked” indicator
Indicates that remote controller but-
tons have been locked.
“Clean The Filter” indicator
To be displayed on when it is time to
clean the filter.
Timer indicators
The indicator comes on if the corre-
sponding timer is set.
Up/Down Air Direction indica-
tor
The indicator shows the direc-
tion of the outcoming airflow.
“One Hour Only” indicator
Room Temperature display
Shows the room temperature. The room
temperature display range is 46–102˚F.
The display blinks if the temperature
is less than 46˚F or 102˚F or more.
Louver display
Indicates the action of the swing louver.
Does not appear if the louver is not
running.
(Power On indicator)
Indicates that the power is on.
Fan Speed indicator
Shows the selected fan speed.
Ventilation indicator
Appears when the unit is running in
Ventilation mode.
Operation Section
Temperature setting buttons
Down
Up
Timer Menu button
(Monitor/Set button)
Mode button (Return button)
Set Time buttons
Back
Ahead
Timer On/Off button
(Set Day button)
Opening the
lid
ON/OFF button
Fan Speed button
Filter button
(<Enter> button)
Test Run button
Check button (Clear button)
Airflow Up/Down button
Louver button
( Operation button)
To return operation
number
Ventilation button
( Operation button)
To go to next operation
number
Note:
“PLEASE WAIT” message
This message is displayed for approximately 3 minutes when power is supplied to the indoor unit or when the unit is recovering from a power failure.
“NOT AVAILABLE” message
This message is displayed if an invalid button is pressed (to operate a function that the indoor unit does not have).
If a single remote controller is used to operate multiple indoor units simultaneously that are different types, this message will not be displayed as
far as any of the indoor units is equipped with the function.
Built-in temperature sensor
Displayed if the airflow is set to
low or downward during COOL
or DRY mode. (Operation varies
according to model.)
The indicator goes off in 1 hour,
when the airflow direction
also changes.
LWiredremote controller

7
LWirelessremote controller
ON/OFF TEMP
FAN
VANE
TEST RUN
AUTO STOP
AUTO START
h
min
LOUVER
MODE
CHECK
RESETSET CLOCK
MODEL
SELECT
NOT AVAILABLE
SWING
CHECK
FAN
TEST
RUN
°F
°C
AMPMSTOP
START
AMPM
COOL
DRY
AUTO
FAN
HEAT
VANE CONTROL button
Changes the air flow direction.
CLOCK button
RESET button
SET button
ON/OFF button
The unit is turned ON and OFF alternately
each time the button is pressed.
LOUVER button
Changes left / right airflow direction.
(Not available for this model.)
MODE SELECT button
Switches the operation mode between
COOLING/DRY/FAN/HEATING and AUTO
mode.
+In case the outdoor unit is cooling only
type, the heating and auto mode are not
available.
CHECK-TEST RUN button
Performs an inspection check or test
operation. Do not use it for normal
operation.
FAN SPEED SELECT button
Changes the fan speed.
TIMER display
Displays when in timer operation or when
setting timer.
button
Sets any desired room temperature.
CLOCK display
Displays the current time.
“” “ ” display
Displays the order of timer operation.
“ ” “ ” display
Displays whether timer is on or off.
Buttons used to set the “hour and minute” of
the current time and timer settings.
"h" and "min" buttons
Temperature setting display
Indicates the desired temperature setting
which is set.
display
Displays selected fan speed.
display
The vertical direction of airflow is indicated.
display
Blinks when model is selected.
display
Lights up while the signal is transmitted to
the indoor unit when the button is pressed.
display
Indicate that the unit is being checked or
test-run.
OPERATION MODE display
OPERATION MODE display
Indicates which operation mode is in effect.
TIMER CONTROL buttons
AUTO STOP (OFF timer): when this switch
is set, the air conditioner will be
automatically stopped at the preset time.
AUTO START (ON timer): when this switch is
set, the air conditioner will be automatically
started at the preset time.
MODEL SELECT
CHECK TEST RUN

8
Service Ref.
Power supply (phase, cycle, voltage)
Max. Fuse Size
Min. Circuit Ampacity
External finish (Panel)
Heat exchanger
Fan Fan (drive) %No.
Fan motor output
Fan motor
Airflow (Low-Medium2-Medium1-High)
External static pressure
Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions
Weight
Single phase,60Hz, 208/230V
15
1
Munsell 6.4Y 8.9/0.4
Plate fin coil
Turbo fan (direct) %1
0.05
0.51
Dry: 12-14-16-18(420-490-570-640)
Wet:11-13-15-17(390-460-530-600)
0(direct blow)
–
Remote controller & built-in
28-29-31-32
32 (1-1/4)
PLA-A18BA, PLA-A18BA1
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 258 (10-3/16) PANEL : 35 (1-3/8)
UNIT : 22 (49) PANEL: 6 (13)
A
A
kW
F.L.A.
*/min(CFM)
Pa(mmAq)
kW
dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)
kg(lbs)
W
D
H
INDOOR UNIT
Single phase,60Hz, 208/230V
15
1
Munsell 6.4Y 8.9/0.4
Plate fin coil
Turbo fan (direct) %1
0.05
0.51
Dry: 11-12-13-15(390-420-460-530)
Wet: 10-11-12-14(350-390-420-490)
0(direct blow)
–
Remote controller & built-in
27-28-29-31
32 (1-1/4)
A
A
kW
F.L.A.
*/min(CFM)
Pa(mmAq)
kW
dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)
kg(lbs)
Service Ref.
Power supply (phase, cycle, voltage)
Max. Fuse Size
Min. Circuit Ampacity
External finish (Panel)
Heat exchanger
Fan Fan (drive) %No.
Fan motor output
Fan motor
Airflow (Low-Medium2-Medium1-High)
External static pressure
Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions
Weight
W
D
H
INDOOR UNIT
PLA-A12BA, PLA-A12BA1
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 258 (10-3/16) PANEL : 35 (1-3/8)
UNIT : 22 (49) PANEL: 6 (13)
SPECIFICATIONS
5
PLA-A24BA, PLA-A24BA1
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 258 (10-3/16) PANEL : 35 (1-3/8)
UNIT : 23 (51) PANEL: 6 (13)
Single phase,60Hz, 208/230V
15
1
Munsell 6.4Y 8.9/0.4
Plate fin coil
Turbo fan (direct) %1
0.05
0.51
Dry: 12-14-16-18(420-490-570-640)
Wet: 11-13-15-17(390-460-530-600)
0(direct blow)
–
Remote controller & built-in
28-29-31-32
32(1-1/4)
A
A
kW
F.L.A.
*/min(CFM)
Pa(mmAq)
kW
dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)
kg(lbs)
W
D
H
INDOOR UNIT
Service Ref.
Power supply (phase, cycle, voltage)
Max. Fuse Size
Min. Circuit Ampacity
External finish (Panel)
Heat exchanger
Fan Fan (drive) %No.
Fan motor output
Fan motor
Airflow (Low-Medium2-Medium1-High)
External static pressure
Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions
Weight

9
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 298 (11-3/4) PANEL : 35 (1-3/8)
UNIT : 25 (55) PANEL : 6 (13)
PLA-A36BA, PLA-A36BA1
Single phase,60Hz, 208/230V
15
2
Munsell 6.4Y 8.9/0.4
Plate fin coil
Turbo fan (direct) %1
0.12
1.00
Dry: 20-23-26-30(710-810-920-1060)
Wet: 19-22-25-29(670-770-880-1030)
0(direct blow)
–
Remote controller & built-in
32-34-37-40
32(1-4)
A
A
kW
F.L.A.
*/min(CFM)
Pa(mmAq)
kW
dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)
kg(lbs)
Service Ref.
Power supply (phase, cycle, voltage)
Max. Fuse Size
Min. Circuit Ampacity
External finish (Panel)
Heat exchanger
Fan Fan (drive) %No.
Fan motor output
Fan motor
Airflow (Low-Medium2-Medium1-High)
External static pressure
Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions
Weight
W
D
H
INDOOR UNIT
Service Ref.
Power supply (phase, cycle, voltage)
Max. Fuse Size
Min. Circuit Ampacity
External finish (Panel)
Heat exchanger
Fan Fan (drive) %No.
Fan motor output
Fan motor
Airflow (Low-Medium2-Medium1-High)
External static pressure
Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions
Weight
PLA-A30BA, PLA-A30BA1
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 258 (10-3/16) PANEL : 35 (1-3/8)
UNIT : 23 (51) PANEL: 6 (13)
Single phase,60Hz, 208/230V
15
1
Munsell 6.4Y 8.9/0.4
Plate fin coil
Turbo fan (direct) %1
0.05
0.51
Dry: 14-16-18-21(490-570-640-740)
Wet: 13-15-17-20(460-530-600-710)
0(direct blow)
–
Remote controller & built-in
28-30-32-34
32(1-1/4)
A
A
kW
F.L.A.
*/min(CFM)
Pa(mmAq)
kW
dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)
kg(lbs)
W
D
H
INDOOR UNIT
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 298 (11-3/4) PANEL : 35 (1-3/8)
UNIT : 25 (55) PANEL : 6 (13)
PLA-A42BA, PLA-A42BA1
Single phase,60Hz, 208/230V
15
2
Munsell 6.4Y 8.9/0.4
Plate fin coil
Turbo fan (direct) %1
0.12
1.00
Dry: 22-25-28-31(780-880-990-1090)
Wet: 21-24-27-30(740-850-950-1060)
0(direct blow)
–
Remote controller & built-in
34-36-39-41
32(1-1/4)
A
A
kW
F.L.A.
*/min(CFM)
Pa(mmAq)
kW
dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)
kg(lbs)
W
D
H
INDOOR UNIT
Service Ref.
Power supply (phase, cycle, voltage)
Max. Fuse Size
Min. Circuit Ampacity
External finish (Panel)
Heat exchanger
Fan Fan (drive) o No.
Fan motor output
Fan motor
Airflow (Low-Medium2-Medium1-High)
External static pressure
Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions
Weight

10
6NOISE CRITERION CURVES
PLA-A12BA
PLA-A12BA1
PLA-A18BA
PLA-A18BA1
NOTCH SPL(dB) LINE
High 31
Medium1 29
Medium2 28
Low 27
NOTCH SPL(dB) LINE
High 32
Medium1 31
Medium2 29
Low 28
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD 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 bar) OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 bar)
BAND CENTER FREQUENCIES, Hz
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
PLA-A24BA
PLA-A24BA1
PLA-A30BA
PLA-A30BA1
NOTCH SPL(dB) LINE
High 32
Medium1 31
Medium2 29
Low 28
NOTCH SPL(dB) LINE
High 34
Medium1 32
Medium2 30
Low 28
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 bar) OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 bar)