Mitsubishi Electric PLA-A12EA8 User manual

1
TCH120A
SERVICE MANUAL
CONTENTS
1. REFERENCE MANUAL........................ 2
2. SAFETY PRECAUTION........................ 3
3. PARTS NAMES AND FUNCTIONS...... 6
4. SPECIFICATIONS................................. 7
5. NOISE CRITERION CURVES............. 10
6. OUTLINES AND DIMENSIONS............12
7. WIRING DIAGRAM ............................. 13
8. REFRIGERANT SYSTEM DIAGRAM
...... 14
9. TROUBLESHOOTING ........................ 15
10. FUNCTION SETTING ......................... 30
11. SPECIAL FUNCTION.......................... 31
12. DISASSEMBLY PROCEDURE........... 34
13. REMOTE CONTROLLER ................... 41
PARTS CATALOG (TCB120)
WIRED REMOTE
CONTROLLER
(Option)
INDOOR UNIT
Model name
indication for
MAIN UNIT
Model name
indication for GRILLE
PLA-A12EA8
PLA-A18EA8
PLA-A24EA8
PLA-A30EA8
PLA-A36EA8
PLA-A42EA8
PLA-A48EA8
PLA-A12EA8
PLA-A18EA8
PLA-A24EA8
PLA-A30EA8
PLA-A36EA8
PLA-A42EA8
PLA-A48EA8
Indoor unit
[Model Name] [Service Ref.]
SPLIT-SYSTEM HEAT PUMP
No. TCH120
August 2023
MENU ON
OFF
RETURN SELECT
HOLD
Grille model
[Model Name]
PLP-41EAEU
WIRELESS REMOTE
CONTROLLER
(Option)
REVISED EDITION-A
Revision:
• Some descriptions have been
revised in REVISED EDITION-A
TCH120 is void.

2 3
TCH120A
1REFERENCE MANUAL
OUTDOOR UNIT SERVICE MANUAL
Model Name Service Ref. Service Manual No./Parts Catalog No.
PUZ-A12/18/36/42NKA7
PUZ-A24/30NHA7
PUY-A12/18/36/42NKA7
PUY-A24/30NHA7
PUZ-A12/18/36/42NKA7
PUZ-A24/30NHA7
PUY-A12/18/36/42NKA7
PUY-A24/30NHA7
OCH636 / OCB636
PUZ-A12/18/36/42NKA8
PUZ-A24/30NHA8
PUY-A12/18/36/42NKA8
PUY-A24/30NHA8
PUZ-A12/18/36/42NKA8
PUZ-A24/30NHA8
PUY-A12/18/36/42NKA8
PUY-A24/30NHA8
OCH764 / OCB764
PUZ-HA24NHA1
PUZ-HA30/36NKA
PUZ-HA42NKA1
PUZ-HA24NHA1
PUZ-HA30/36NKA
PUZ-HA42NKA1
OCH750 / OCB750
MXZ-8C48/60NA2
MXZ-4C36NAHZ2
MXZ-5C42NAHZ2
MXZ-8C48NAHZ2
MXZ-8C48/60NA2(-U1)
MXZ-4C36NAHZ2(-U1)
MXZ-5C42NAHZ2(-U1)
MXZ-8C48NAHZ2(-U1)
OCH730 / OCB730
MXZ-3C24/30NA2
MXZ-4C36NA2
MXZ-5C42NA2
MXZ-3C24/30NAHZ2
MXZ-3C24/30NA3
MXZ-4C36NA3
MXZ-5C42NA3
MXZ-3C24/30NAHZ3
MXZ-3C24/30NA4
MXZ-4C36NA4
MXZ-5C42NA4
MXZ-3C24/30NAHZ4
MXZ-3C24/30NA2(-U1)
MXZ-4C36NA2(-U1)
MXZ-5C42NA2(-U1)
MXZ-3C24/30NAHZ2(-U1)
MXZ-3C24/30NA3(-U1)
MXZ-4C36NA3(-U1)
MXZ-5C42NA3(-U1)
MXZ-3C24/30NAHZ3(-U1)
MXZ-3C24/30NA4-U1
MXZ-4C36NA4-U1
MXZ-5C42NA4-U1
MXZ-3C24/30NAHZ4-U1
OBH702 / OBB702
MXZ-SM36/48/60NAM1
MXZ-SM36/42/48NAMHZ1
MXZ-SM36/48/60NAM1-U1
MXZ-SM36/42/48NAMHZ1-U1 OCH789 / OCB789
MXZ-SM72/96/120TAM1 MXZ-SM72/96/120TAM1-U1 OCH800 / OCB800
MXZ-SM36/48/60NAM2
MXZ-SM36/42/48NAMHZ2
MXZ-SM36/48/60NAM2-U1
MXZ-SM36/42/48NAMHZ2-U1 OCH810 / OCB810
PUMY-P36/48/60NKMU4
PUMY-HP36/42/48NKMU2
PUMY-P36/48/60NKMU4
PUMY-HP36/42/48NKMU2 OCH811 / OCB811
Remote controller (Optional parts)
Wired remote controller Wireless remote controller
MENU ON
OFF
RETURN SELECT
HOLD

2 3
TCH120A
SAFETY PRECAUTION
2
Cautions for units utilising refrigerant R410A
2-2. CAUTIONS RELATED TO NEW REFRIGERANT
2-1. ALWAYS OBSERVE FOR SAFETY
Before obtaining access to terminal, all supply circuits must be disconnected.
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.
In case of using the existing pipes for R22, be careful with
the following:
· Be sure to clean the pipes and make sure that the insides
of the pipes are clean.
· Change flare nut to the one provided with this product.
Use a newly flared pipe.
· Avoid using thin pipes.
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.
Handle 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.
· In case of reconnecting the refrigerant pipes after
detaching, make the flared part of pipe re-fabricated.
Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.
Store the piping indoors, and keep both ends
of the piping sealed until just before brazing.
(Leave elbow joints, etc. in their packaging.)
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of compressor.
The refrigerant oil applied to flare and flange
connections must be ester oil, ether oil or
alkylbenzene oil in a small amount.
If large amount of mineral oil enters, that can cause deterio-
ration of refrigerant oil, etc.
Never use any refrigerant other than that specified.
Doing so may cause a burst, an explosion, or fire when the
unit is being used, serviced, or disposed of.
Correct refrigerant is specified in the manuals and on the
spec labels provided with our products.
We will not be held responsible for mechanical failure,
system malfunction, unit breakdown or accidents caused
by failure to follow the instructions.
Use the specified refrigerant only.
Preparation before the repair service.
• Prepare the proper tools.
• Prepare the proper protectors.
• Provide adequate ventilation.
• After stopping the operation of the air conditioner, turn off
the power-supply breaker.
• Discharge the condenser before the work involving the
electric parts.
Precautions during the repair service.
• Do not perform the work involving the electric parts
with wet hands.
• Do not pour water into the electric parts.
• Do not touch the refrigerant.
• Do not touch the hot or cold areas in the refrigerating cycle.
• When the repair or the inspection of the circuit needs to be
done without turning off the power, exercise great caution
not to touch the live parts.
• When opening or closing the valve below freezing
temperatures, refrigerant may spurt out from the gap
between the valve stem and the valve body, resulting in
injuries.

4 5
TCH120A
[1] Warning for service
(1) Do not alter the unit.
(2) For installation and relocation work, follow the instructions in the Installation Manual and use tools and pipe
components specifically made for use with refrigerant specified in the outdoor unit installation manual.
(3) Ask a dealer or an authorized technician to install, relocate and repair the unit.
(4) This unit should be installed in rooms which exceed the floor space specified in outdoor unit installation manual.
Refer to outdoor unit installation manual.
(5) Install the indoor unit at least 2.5 m above floor or grade level.
For appliances not accessible to the general public.
(6) Refrigerant pipes connection shall be accessible for maintenance purposes.
(7) If the air conditioner is installed in a small room or closed room, measures must be taken to prevent the refri-
gerant concentration in the room from exceeding the safety limit in the event of refrigerant leakage. Should the
refrigerant leak and cause the concentration limit to be exceeded, hazards due to lack of oxygen in the room may
result.
(8) Keep gas-burning appliances, electric heaters, and other fire sources (ignition sources) away from the location
where installation, repair, and other air conditioner work will be performed.
If refrigerant comes into contact with a flame, poisonous gases will be released.
(9) When installing or relocating, or servicing the air conditioner, use only the specified refrigerant written on out-
door unit to charge the refrigerant lines.
Do not mix it with any other refrigerant and do not allow air to remain in the lines.
If air is mixed with the refrigerant, then it can be the cause of abnormal high pressure in the refrigerant line, and
may result in an explosion and other hazards.
(10) After installation has been completed, check for refrigerant leaks. If refrigerant leaks into the room and comes
into contact with the flame of a heater or portable cooking range, poisonous gases will be released.
(11) Do not use low temperature solder alloy in case of brazing the refrigerant pipes.
(12) When performing brazing work, be sure to ventilate the room sufficiently. Make sure that there are no hazardous
or flammable materials nearby.
When performing the work in a closed room, small room, or similar location, make sure that there are no refrige-
rant leaks before performing the work.
If refrigerant leaks and accumulates, it may ignite or poisonous gases may be released.
(13) Do not install the unit in places where refrigerant may build-up or places with poor ventilation such as a semi-
basement or a sunken place in outdoor: Refrigerant is heavier than air, and inclined to fall away from the leak
source.
(14) Do not use means to accelerate the defrosting process or to clean, other than those recommended by the manu-
facturer.
(15) The appliance shall be stored in a room without continuously operating ignition sources (for example: open
flames, an operating gas appliance or an operating electric heater).
(16) Do not pierce or burn.
(17) Be aware that refrigerants may not contain an odour.
(18) Pipe-work shall be protected from physical damage.
(19) The installation of pipe-work shall be kept to a minimum.
(20) Compliance with national gas regulations shall be observed.
(21) Keep any required ventilation openings clear of obstruction.
(22) Servicing shall be performed only as recommended by the manufacturer.
(23) The appliance shall be stored in a well-ventilated area where the room size corresponds to the room area as
specified for operation.
(24) Maintenance, service and repair operations shall be performed by authorized technician with required qualifica-
tion.

4 5
TCH120A
Electronic weighing scale
Unit
[4] Service tools
Use the below service tools as exclusive tools for R410A refrigerant.
[3] Additional refrigerant charge
When charging directly from cylinder
(1) Check that cylinder for R410A on the market is a syphon type.
(2) Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.)
[2] 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.
No. Tool name Specifications
1Gauge manifold · Use the existing fitting specifications. (UNF1/2)
· Use high-tension side pressure of 768.7 PSIG [5.3MPa·G] or over.
2Charge hose · Use pressure performance of 738.2 PSIG [5.09MPa·G] or over.
3Electronic weighing scale —
4Gas leak detector · Use the detector for R410A.
5Adaptor for reverse flow check · Attach on vacuum pump.
6Refrigerant charge base —
7Refrigerant cylinder · Top of cylinder (R410A refrigerant)
· Cylinder with syphon
8Refrigerant recovery equipment —

6 7
TCH120A
3PARTS NAMES AND FUNCTIONS
Drain pipe
Filter
Vane
Gas pipe
Liquid pipe
Air outlet
Air intake
(Intake grille)
i-see Sensor
(Option)
Signal receiver
(Option)
Model name
indication for
MAIN UNIT
Model name
indication for GRILLE

6 7
TCH120A
SPECIFICATIONS
4
INDOOR UNIT
Service Ref. PLA-A12EA8
Power supply (phase, cycle, voltage) Single phase, 60 Hz, 208/230 V
Max. Fuse Size A 15
Min Circuit Ampacity A 1
External nish (Panel) PLP-41EAEU: Munsell 1.0Y 9.2/0.2
Heat exchanger Plate n coil
Fan Fan (drive) × No. Turbo fan (direct) × 1
Fan motor output kW 0.05
Fan motor F.L.A. 0.28
Airow (Low-Medium2-Medium1-High) CFM (m³/min) 370-460-490-530 (10.5-13-14-15)
External static pressure
Pa (mmAq) 0 (direct blow)
Booster heater kW –
Operation control & Thermostat Remote controller & built-in
Noise level (Low-Medium2-Medium1-High) dB 26-27-29-30
Field drain pipe O.D. inch (mm) 1-1/4 (32)
Dimensions W inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
D inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
H inch (mm) MAIN UNIT: 10-3/16 (258) PANEL: 1-9/16 (40)
Weight lb (kg) MAIN UNIT: 46 (21) PANEL: 11 (5)
INDOOR UNIT
Service Ref. PLA-A18EA8
Power supply (phase, cycle, voltage) Single phase, 60 Hz, 208/230 V
Max. Fuse Size A 15
Min Circuit Ampacity A 1
External nish (Panel) PLP-41EAEU: Munsell 1.0Y 9.2/0.2
Heat exchanger Plate n coil
Fan Fan (drive) × No. Turbo fan (direct) × 1
Fan motor output kW 0.05
Fan motor F.L.A. 0.28
Airow (Low-Medium2-Medium1-High) CFM (m³/min) 460-490-570-600 (13-14-16-17)
External static pressure
Pa (mmAq) 0 (direct blow)
Booster heater kW –
Operation control & Thermostat Remote controller & built-in
Noise level (Low-Medium2-Medium1-High) dB 28-29-31-32
Field drain pipe O.D. inch (mm) 1-1/4 (32)
Dimensions W inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
D inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
H inch (mm) MAIN UNIT: 10-3/16 (258) PANEL: 1-9/16 (40)
Weight lb (kg) MAIN UNIT: 46 (21) PANEL: 11 (5)
INDOOR UNIT
Service Ref. PLA-A24EA8
Power supply (phase, cycle, voltage) Single phase, 60 Hz, 208/230 V
Max. Fuse Size A 15
Min Circuit Ampacity A 1
External nish (Panel) PLP-41EAEU: Munsell 1.0Y 9.2/0.2
Heat exchanger Plate n coil
Fan Fan (drive) × No. Turbo fan (direct) × 1
Fan motor output kW 0.12
Fan motor F.L.A. 0.56
Airow (Low-Medium2-Medium1-High) CFM (m³/min) 530-640-710-810 (15-18-20-23)
External static pressure
Pa (mmAq) 0 (direct blow)
Booster heater kW –
Operation control & Thermostat Remote controller & built-in
Noise level (Low-Medium2-Medium1-High) dB 28-30-33-36
Field drain pipe O.D. inch (mm) 1-1/4 (32)
Dimensions W inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
D inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
H inch (mm) MAIN UNIT: 11-3/4 (298) PANEL: 1-9/16 (40)
Weight lb (kg) MAIN UNIT: 57 (26) PANEL: 11 (5)

8 9
TCH120A 8
INDOOR UNIT
Service Ref. PLA-A30EA8
Power supply (phase, cycle, voltage) Single phase, 60 Hz, 208/230 V
Max. Fuse Size A 15
Min Circuit Ampacity A 1
External nish (Panel) PLP-41EAEU: Munsell 1.0Y 9.2/0.2
Heat exchanger Plate n coil
Fan Fan (drive) × No. Turbo fan (direct) × 1
Fan motor output kW 0.12
Fan motor F.L.A. 0.56
Airow (Low-Medium2-Medium1-High) CFM (m³/min) 570-670-780-880 (16-19-22-25)
External static pressure
Pa (mmAq) 0 (direct blow)
Booster heater kW –
Operation control & Thermostat Remote controller & built-in
Noise level (Low-Medium2-Medium1-High) dB 28-32-35-38
Field drain pipe O.D. inch (mm) 1-1/4 (32)
Dimensions W inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
D inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
H inch (mm) MAIN UNIT: 11-3/4 (298) PANEL: 1-9/16 (40)
Weight lb (kg) MAIN UNIT: 57 (26) PANEL: 11 (5)
INDOOR UNIT
Service Ref. PLA-A36EA8
Power supply (phase, cycle, voltage) Single phase, 60 Hz, 208/230 V
Max. Fuse Size A 15
Min Circuit Ampacity A 2
External nish (Panel) PLP-41EAEU: Munsell 1.0Y 9.2/0.2
Heat exchanger Plate n coil
Fan Fan (drive) × No. Turbo fan (direct) × 1
Fan motor output kW 0.12
Fan motor F.L.A. 0.56
Airow (Low-Medium2-Medium1-High) CFM (m³/min) 670-850-1020-1200 (19-24-29-34)
External static pressure
Pa (mmAq) 0 (direct blow)
Booster heater kW –
Operation control & Thermostat Remote controller & built-in
Noise level (Low-Medium2-Medium1-High) dB 32-37-41-44
Field drain pipe O.D. inch (mm) 1-1/4 (32)
Dimensions W inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
D inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
H inch (mm) MAIN UNIT: 11-3/4 (298) PANEL: 1-9/16 (40)
Weight lb (kg) MAIN UNIT: 57 (26) PANEL: 11 (5)
INDOOR UNIT
Service Ref. PLA-A42EA8
Power supply (phase, cycle, voltage) Single phase, 60 Hz, 208/230 V
Max. Fuse Size A 15
Min Circuit Ampacity A 2
External nish (Panel) PLP-41EAEU: Munsell 1.0Y 9.2/0.2
Heat exchanger Plate n coil
Fan Fan (drive) × No. Turbo fan (direct) × 1
Fan motor output kW 0.12
Fan motor F.L.A. 0.56
Airow (Low-Medium2-Medium1-High) CFM (m³/min) 740-920-1060-1200 (21-26-30-34)
External static pressure
Pa (mmAq) 0 (direct blow)
Booster heater kW –
Operation control & Thermostat Remote controller & built-in
Noise level (Low-Medium2-Medium1-High) dB 34-38-42-45
Field drain pipe O.D. inch (mm) 1-1/4 (32)
Dimensions W inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
D inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
H inch (mm) MAIN UNIT: 11-3/4 (298) PANEL: 1-9/16 (40)
Weight lb (kg) MAIN UNIT: 57 (26) PANEL: 11 (5)

8 9
TCH120A
8
INDOOR UNIT
Service Ref. PLA-A48EA8
Power supply (phase, cycle, voltage) Single phase, 60 Hz, 208/230 V
Max. Fuse Size A 15
Min Circuit Ampacity A 2
External nish (Panel) PLP-41EAEU: Munsell 1.0Y 9.2/0.2
Heat exchanger Plate n coil
Fan Fan (drive) × No. Turbo fan (direct) × 1
Fan motor output kW 0.12
Fan motor F.L.A. 0.56
Airow (Low-Medium2-Medium1-High) CFM (m³/min) 740-920-1060-1200 (21-26-30-34)
External static pressure
Pa (mmAq) 0 (direct blow)
Booster heater kW –
Operation control & Thermostat Remote controller & built-in
Noise level (Low-Medium2-Medium1-High) dB 34-38-42-45
Field drain pipe O.D. inch (mm) 1-1/4 (32)
Dimensions W inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
D inch (mm) MAIN UNIT: 33-1/16 (840) PANEL: 37-13/32 (950)
H inch (mm) MAIN UNIT: 11-3/4 (298) PANEL: 1-9/16 (40)
Weight lb (kg) MAIN UNIT: 57 (26) PANEL: 11 (5)

1110 11
TCH120A
5NOISE CRITERION CURVES
PLA-A12EA8 PLA-A18EA8
NOTCH SPL(dB) LINE
High 30
Medium1 29
Medium2 27
Low 26
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-A24EA8 PLA-A30EA8
NOTCH SPL(dB) LINE
High 36
Medium1 33
Medium2 30
Low 28
NOTCH SPL(dB) LINE
High 38
Medium1 35
Medium2 32
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)

11
TCH120A
10 11
PLA-A36EA8 PLA-A42EA8
PLA-A48EA8
NOTCH SPL(dB) LINE
High 44
Medium1 41
Medium2 37
Low 32
NOTCH SPL(dB) LINE
High 45
Medium1 42
Medium2 38
Low 34
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)
MAIN UNIT
5 ft
MICROPHONE
CEILING

12 13
TCH120A
PLA-A12EA8 PLA-A18EA8 PLA-A24EA8 PLA-A30EA8
PLA-A36EA8 PLA-A42EA8 PLA-A48EA8
6OUTLINES AND DIMENSIONS
Unit: inch (mm)
16-9/16(420)
16-9/16(420)
PLA-A12/18EA8 PLA-A24~48EA8

12 13
TCH120A
PLA-A12EA8 PLA-A18EA8 PLA-A24EA8 PLA-A30EA8
PLA-A36EA8 PLA-A42EA8 PLA-A48EA8
7WIRING DIAGRAM

14 15
TCH120A
Pipe temperature
thermistor/liquid (TH2)
Distributor
with strainer (#50)
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)
8REFRIGERANT SYSTEM DIAGRAM
PLA-A12EA8 PLA-A18EA8 PLA-A24EA8 PLA-A30EA8
PLA-A36EA8 PLA-A42EA8 PLA-A48EA8

14 15
TCH120A
9 TROUBLESHOOTING
<Check code displayed by self-diagnosis and actions to be taken for service (summary)>
Present and past check codes are logged, and they can be displayed on the wired remote controller and control board of out-
door unit. Actions to be taken for service, which depends on whether or not the trouble is reoccurring in the field, are summa-
rized in the table below. Check the contents below before investigating details.
9-1. TROUBLESHOOTING
Unit conditions at service Check code Actions to be taken for service (summary)
The trouble is reoccurring.
Displayed Judge the problem and take a corrective action according
to “9-3. SELF-DIAGNOSIS ACTION TABLE”.
Not displayed
Conduct troubleshooting and ascertain the cause of the
trouble according to “9-4. TROUBLESHOOTING OF
PROBLEMS”.
The trouble is not reoccurring.
Logged
Consider the temporary defects such as the work of
protection devices in the refrigerant circuit including
compressor, poor connection of wiring, noise, etc.
Re-check the symptom, and check the installation
environment, refrigerant amount, weather when the
trouble occurred, matters related to wiring, etc.
Reset check code logs and restart the unit after finishing
service.
There is no abnormality in electrical component,
controller board, remote controller, etc.
Not logged
Re-check the abnormal symptom.
Conduct troubleshooting and ascertain the cause of the
trouble according to “9-4. TROUBLESHOOTING OF
PROBLEMS”.
Continue to operate unit for the time being if the cause
is not ascertained.
There is no abnormality concerning of parts such as
electrical component, controller board, remote controller,
etc.

16 17
TCH120A
OPERATION
INDICATOR
lamp blink
pattern
peeBpeeBpeeBpeeBpeeB Beep Beep
Off
Approx. 2.5 s
On
Approx. 3 s
On
0.5 s
On
0.5 s
On
0.5 s
On
0.5 s
Off
Approx. 2.5 s
On
Approx. 3 s
On
0.5 s
On
0.5 s
· · · Repeated
Number of blinks/beeps in pattern indicates the check
code in the following table (i.e., n=5 for “U2”)
Number of blinks/beeps in pattern indicates
the check code in the following table
n
th
1
st
2
nd
3
rd
1
st
2
nd
Self-check
starts
(Start signal
received)
Beeper sounds
[Output pattern B]
OPERATION
INDICATOR
lamp blink
pattern
Beep Beep Beep Beep Beep Beep Beep
Off
Approx. 2.5 s
On
0.5 s
On
0.5 s
On
0.5 s
On
0.5 s
Off
Approx. 2.5 s
On
0.5 s
On
0.5 s
· · · Repeated
Number of blinks/beeps in pattern indicates the check
code in the following table (i.e., n=5 for “P5”)
Number of blinks/beeps in pattern indicates
the check code in the following table
n
th
1
st
2
nd
3
rd
1
st
2
nd
Self-check
starts
(Start signal
received)
Beeper sounds
• Refer to “13-7. SELF-DIAGNOSIS” to search for the error history.
[Output pattern A]
[Output pattern B] Errors detected by unit other than indoor unit (outdoor unit, etc.)
Wireless remote controller Wired remote controller
Symptom Remarks
Beeper sounds/OPERATION
INDICATOR lamp blinks
(Number of times)
Check code
1 E9 Indoor/outdoor unit communication error
(Transmitting error) (Outdoor unit)
For details, check the LED
display of the outdoor
controller board.
As for outdoor unit, refer
to outdoor unit's service
manual.
2 UP Compressor overcurrent interruption
3 U3,U4 Open/short of outdoor unit thermistors
4 UF Compressor overcurrent interruption (When compressor locked)
5 U2 Abnormal high discharge temperature/49C operated/
insu󰀩cient refrigerant
6 U1,Ud (UD)* Abnormal high pressure (63H operated)/Overheating
protection operation
7 U5 Abnormal temperature of heat sink
8 U8 Outdoor unit fan protection stop
9 U6 Compressor overcurrent interruption/Abnormal of power module
10 U7 Abnormality of super heat due to low discharge temperature
11 U9,UH Abnormality such as overvoltage or voltage shortage and abnormal
synchronous signal to main circuit/Current sensor error
12 - -
13 - -
14 Others Other errors (Refer to the technical manual for the outdoor unit.)
Notes:
1. If the beeper does not sound again after the initial 2 beeps to conrm 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 3 times continuously “beep, beep, beep (0.4 + 0.4 + 0.4 seconds)” after the initial 2 beeps to conrm the self-check start signal
was received, the specied refrigerant address is incorrect.
[Output pattern A] Errors detected by indoor unit
Wireless remote controller Wired remote controller
Symptom Remarks
Beeper sounds/OPERATION
INDICATOR lamp blinks
(Number of times)
Check code
1 P1 Intake sensor error
2P2 Pipe (TH2) sensor error
P9 Pipe (TH5) sensor error
3 E6,E7 Indoor/outdoor unit communication error
4 P4 Drain sensor error/Float switch connector (CN4F) open
5P5 Drain pump error
PA Forced compressor stop(due to water leakage abnormality)
6 P6 Freezing/Overheating protection operation
7 EE Combination error between indoor and outdoor units
8 P8 Pipe temperature error
9 E4, E5 Remote controller signal receiving error
10 – –
11 Pb Indoor unit fan motor error
12 Fb (FB)* Indoor unit control system error (memory error, etc.)
14 PL Abnormal refrigerant circuit
No sound E0, E3 Remote controller transmission error
No sound E1, E2 Remote controller control board error
No sound – – – – No corresponding

16 17
TCH120A
• On wireless remote controller
The continuous buzzer sounds from receiving section of indoor unit.
Blink of operation lamp
• On wired remote controller
Check code displayed in the LCD.
* The check code in the parenthesis indicates PAR-41MAA model.
● If the unit cannot be operated properly after test run, refer to the following table to nd the cause.
Symptom Cause
Wired remote controller LED 1, 2 (PCB in outdoor unit)
Please Wait For about 3
minutes after
power-on
After LED 1, 2 are lit, LED 2 is turned
o󰀨, then only LED 1 is lit.
(Correct operation)
• For about 3 minutes following power-on, operation
of the remote controller is not possible due to
system startup. (Correct operation)
Please Wait → Check code
Subsequent to
about 3 minutes
after power-on
Only LED 1 is lit.
→ LED 1, 2 blink.
• 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, GR).
Display messages do not
appear even when operation
switch is turned ON (operation
lamp does not light up).
Only LED 1 is lit.
→ LED 1 blinks twice,
LED 2 blinks once.
• Incorrect wiring between indoor and outdoor units
(incorrect polarity of S1, S2, S3)
• Remote controller wire short
On the wireless remote controller with condition above, following phenomena take place.
• No signals from the remote controller can be received.
• Operation 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)
For description of each LED (LED1, 2, 3) provided on the indoor controller, refer to the following table.
LED1 (power for microprocessor) Indicates whether control power is supplied. Make sure that this LED is
always lit.
LED2 (power for remote controller) 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 addresses “0”.
LED3 (communication between indoor and outdoor units) Indicates state of communication between the indoor and outdoor units.
Make sure that this LED is always blinking.

18 19
TCH120A
9-3. SELF-DIAGNOSIS ACTION TABLE
Note:
Errors to be detected in outdoor unit, such as codes starting with F, U or E (excluding E0 to E7),
are not covered in this document. Please refer to the outdoor unit service manual for the details.
Check code Abnormal point and detection method Cause Countermeasure
P1
Room temperature thermistor (TH1)
1The unit is in 3-minute resume
prevention mode if short/open of
thermistor is detected. Abnormal if the
unit does not reset normally after 3 min-
utes. (The unit returns to normal opera-
tion, if it has been reset normally.)
2Constantly detected during cooling,
drying, and heating operation.
Short: 194°F [90:] or more
Open: −40°F [−40:] 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.
32°F [0:]....15.0 k"
50°F [10:]......9.6 k"
68°F [20:]......6.3 k"
86°F [30:]......4.3 k"
104°F [40:]......3.0 k"
If you put force on (draw or bend) the lead
wire with measuring resistance value of
thermistor, breaking of wire or contact fail-
ure can be detected.
2Check contact failure of connector (CN20)
on the indoor controller board. Refer to
"9-7. TEST POINT DIAGRAM".
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 3-minute resume
prevention mode if short/open of
thermistor is detected. Abnormal if the
unit does not reset normally after 3 min-
utes. (The unit returns to normal opera-
tion, if it has been reset normally.)
2Constantly detected during cooling,
drying, and heating (except defrosting)
operation
Short: 194°F [90:] or more
Open: −40°F [−40:] 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 194°F [90:] or more, or
−40°F [−40:] 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
"9-7. TEST POINT DIAGRAM".
Turn the power on 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 extremely difference with actual
pipe <liquid> temperature, replace indoor
controller board.
Turn the power off, and on again to operate
after check.
P4
Contact failure of drain float switch
(CN4F)
• Extract when the connector of drain float
switch is disconnected.
(3and 4of connector CN4F is not
short-circuited.)
• Constantly detected during operation
1Contact failure of connector
(Insert failure)
2Defective indoor controller
board
1Check contact failure of float switch con-
nector.
Turn the power on again and check after
inserting connector again.
2
Operate with connector (CN4F) short-circuited.
Replace indoor controller board if abnormality reap-
pears.

18 19
TCH120A
Check code Abnormal point and detection method Cause Countermeasure
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.
Compressor and indoor fan will be turned
off.
2Drain pump is abnormal if the condition
above is detected during suspensive
abnormality.
3Constantly detected during drain pump
operation
Drain pump lock protection operation
1Error postponement, if drain pump stops
for 5 seconds continuously while drain
pump is operating.
2Drain pump is abnormal if above condi-
tion is repeated 4 times after error post-
ponement is detected.
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
1Malfunction of drain pump
2Clogged drain pump
3Contact failure of connector
4Defective indoor controller
board
1Check if drain-up machine works.
2Check drain function.
3
Remove 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.
4
Replace indoor controller board if it is short-circuit-
ed between 3–4of the drain float switch connec-
tor 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.
1Check if drain pump works.
2Check if drain pump works.
3Check contact failure of connector CNP
4Press the indoor emergency switch
(SWE) to check the voltage between
CNP1-3.
• If
13 V DC, replace the drain pump.
• If not 13 V DC, replace the indoor con-
troller board.
P6
Freezing/overheating protection is work-
ing
1Freezing protection (Cooling mode)
The unit is in 6-minute resume preven-
tion mode if pipe <liquid or condenser/
evaporator> temperature stays under
−5°F [−15:] for 3 minutes, 3 minutes
after the compressor started.
Abnormal if it stays under −5°F [−15:]
for 3 minutes again within 16 minutes
after 6-minute resume prevention mode.
2Overheating protection (Heating mode)
The unit is in 6-minute resume
prevention mode if pipe <liquid or con-
denser/evaporator> temperature is
detected as over 158°F [70:] after the
compressor started. Abnormal if the tem-
perature of over 158°F [70:] is detected
again within 30 minutes after 6-minute
resume prevention mode.
(Cooling or drying mode)
1Clogged filter (reduced airflow)
2Short cycle of air path
3Low-load (low temperature)
operation out of the tolerance
range
4Defective indoor fan motor
• Fan motor is defective.
• Indoor controller board is defec-
tive.
5Defective outdoor fan control
6Overcharge of refrigerant
7Defective refrigerant circuit
(clogs)
(Heating mode)
1Clogged filter (reduced airflow)
2Short cycle of air path
3Overload (high temperature)
operation out of the tolerance
range
4Defective indoor fan motor
• Fan motor is defective.
• Indoor controller board is defec-
tive.
5Defective outdoor fan control
6Overcharge of refrigerant
7Defective refrigerant circuit
(clogs)
8Bypass circuit of outdoor unit is
defective.
(Cooling or drying mode)
1Check clogs of the filter.
2Remove shields.
4Refer to "9-6. HOW TO CHECK THE
PARTS".
5Check outdoor fan motor.
67 Check operating condition of refriger-
ant circuit.
(Heating mode)
1Check clogs of the filter.
2Remove shields.
4Refer to "9-6. HOW TO CHECK THE
PARTS".
5Check outdoor fan motor.
6–8Check operating condition of refriger-
ant circuit.
( (

20 21
TCH120A
Check code Abnormal point and detection method Cause Countermeasure
P8
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: −5.4°F [−3°C] ] (TH−TH1)
TH: Lower temperature between liquid pipe
temperature (TH2) and condenser/
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 heat-
ing 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 defrosting
mode is over.)
Heating range: 5.4°F [3°C] [ (TH5−TH1)
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.
1–4 Check pipe <liquid or condenser/
evaporator> temperature with room
temperature display on remote con-
troller and outdoor controller circuit
board.
Pipe <liquid or condenser/evapora-
tor> temperature display is indicated
by setting SW2 of outdoor controller
circuit board as follows.
Conduct temperature check with outdoor
controller circuit board after connecting
‘A-Control Service Tool(PAC-SK52ST)’.
23Check converse connection of exten-
sion pipe or converse wiring of indoor/
outdoor unit connecting wire.
P9
Pipe temperature thermistor/Condensor-
Evaporator (TH5)
1The unit is in 3-minute resume protec-
tion mode if short/open of thermistor is
detected. Abnormal if the unit does not
get back to normal within 3 minutes. (The
unit returns to normal operation, if it has
been reset normally.)
2Constantly detected during cooling,
drying, and heating operation (except
defrosting)
Short: 194°F [90:] or more
Open: −40°F [−40:] 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
194°F [90:] or more or −40°F
[−40:] or less caused by
defective refrigerant circuit.
5Defective indoor controller
board
1–3
Check resistance value of thermistor.
For characteristics, refer to (P1).
2Check contact failure of connector (CN44)
on the indoor controller board.
Refer to "9-7. TEST POINT DIAGRAM".
Turn the power on and check restart
after inserting connector again.
4 Operate in test run mode and check pipe
<condenser/evaporator> temperature with
outdoor controller circuit board. If pipe
<condenser/evaporator> temperature is
extremely low (in cooling mode) or high (in
heating mode), refrigerant circuit may have
defect.
5 Operate in test run mode and check pipe
<condenser/evaporator> temperature with
outdoor control circuit board. If there is
extreme difference with actual pipe
<condenser/evaporator> temperature,
replace indoor controller board.
There is no abnormality if none of above
comes within the unit.
Turn the power off and on again to operate.
In case of checking pipe temperature with outdoor
controller circuit board, be sure to
connect A-control service tool (PAC-SK52ST).
( (
( (