Mitsubishi Electric Mr.SLIM PUZ-HA24NHA User manual

SERVICE MANUAL
CONTENTS
1. REFERENCE MANUAL····························· 2
2. SAFETY PRECAUTION····························· 2
3. FEATURES ············································· 6
4. SPECIFICATIONS ···································· 7
5. DATA······················································ 8
6. OUTLINES AND DIMENSIONS················· 10
7. WIRING DIAGRAM································· 11
8. WIRING SPECIFICATIONS ······················ 12
9. REFRIGERANT SYSTEM DIAGRAM ············ 16
10. TROUBLESHOOTING ····························· 17
11. EASY MAINTENANCE FUNCTION ············ 70
12. FUNCTION SETTING ······························ 72
13. MONITORING THE OPERATION DATA BY THE REMOTE CONTROLLER ··········77
14. DISASSEMBLY PROCEDURE ·················· 87
R410A
Notes:
• This manual describes service
data of the outdoor units only.
[Model Name]
PUZ-HA24NHA
[Service Ref.]
PUZ-HA24NHA
PARTS CATALOG (OCB721)
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
No. OCH721
REVISED EDITION-A
October 2019
Revision:
• Some descriptions have
been modified
in REVISED EDITION-A.
OCH721 is void.

2
OCH721A
2SAFETY PRECAUTION
1REFERENCE MANUAL
Before obtaining access to terminal, all supply circuits must be disconnected.
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 beaker.
• 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.
2-1. ALWAYS OBSERVE FOR SAFETY
INDOOR UNIT
Model name Service Ref. Service manual No.
PLA-A24EA7 PLA-A24EA7 OCH640/OCB640
PKA-A24KA7 PKA-A24KA7.TH OCH639/OCB639
PCA-A24KA7 PCA-A24KA7.TH OCH638/OCB638
PEAD-A24AA7 PEAD-A24AA7 HWE1608A/BWE01629A
PVA-A24AA7 PVA-A24AA7 MD-1404-K011/MD-1404-K012

3
OCH721A
Cautions for units utilizing refrigerant R410A
2-2. 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 contaminants
such as sulfur, oxides, dirt, shaving particles, etc.
which are hazard to refrigerant cycle.
In addition, use pipes with specified thickness.
Store the piping indoors, and both ends of the
piping sealed until just before brazing.
(Leave elbow joints, etc. in their packaging.)
The refrigerant oil applied to flare and flange
connections must be ester oil, ether oil or
alkylbenzene oil in a small amount.
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.
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.
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
Use the specified refrigerant only.
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.
Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.

4
OCH721A
Electric weighing scale
Unit
[3] Service tools
Use the below service tools as exclusive tools for R410A refrigerant.
[1] Cautions for service
(1) Perform service after recovering the refrigerant left in 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.
[2] Additional refrigerant charge
When charging directly from cylinder
· Check that cylinder for R410A on the market is a syphon type.
· Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.)
No. Tool name Specifications
1Gauge manifold · Only for R410A
· Use the existing fitting specifications.
· Use high-tension side pressure of 5.3MPa·G or over.
2Charge hose · Only for R410A
· Use pressure performance of 5.09MPa·G or over.
3Electronic weighing scale —
4Gas leak detector · Use the detector for R134a, R407C or R410A.
5Adaptor for reverse flow check · Attach on vacuum pump.
6Refrigerant charge base —
7Refrigerant cylinder · Only for R410A · Top of cylinder (Pink)
· Cylinder with syphon
8Refrigerant recovery equipment —

5
OCH721A
2-3. CAUTIONS FOR REFRIGERANT PIPING WORK
New refrigerant R410A is adopted for replacement inverter series. Although the refrigerant piping work for R410A is same as
for R22, exclusive tools are necessary so as not to mix with different kind of refrigerant. Furthermore as the working pressure
of R410A is 1.6 time higher than that of R22, their sizes of flared sections and flare nuts are different.
1Thickness of pipes
Because the working pressure of R410A is higher compared to R22, be sure to use refrigerant piping with thickness shown
below. (Never use pipes of 7/256 in [0.7 mm] or below.)
Nominal
dimensions (in)
Outside
diameter (mm)
Thickness: in (mm)
R410A R22
1/4 6.35 1/32 [0.8] 1/32 [0.8]
3/8 9.52 1/32 [0.8] 1/32 [0.8]
1/2 12.70 1/32 [0.8] 1/32 [0.8]
5/8 15.88 5/128 [1.0] 5/128 [1.0]
3/4 19.05 — 5/128 [1.0]
2Dimensions of flare cutting and flare nut
The component molecules in HFC refrigerant are smaller compared to conventional refrigerants. In addition to that, R410A
is a refrigerant, which has higher risk of leakage because its working pressure is higher than that of other refrigerants.
Therefore, to enhance air tightness and strength, flare cutting dimension of copper pipe for R410A has been specified sep-
arately from the dimensions for other refrigerants as shown below. The dimension B of flare nut for R410A also has partly
been changed to increase strength as shown below. Set copper pipe correctly referring to copper pipe flaring dimensions
for R410A below. For 1/2 and 5/8 inch pipes, the dimension B changes.
Use torque wrench corresponding to each dimension.
Dimension A
Dimension B
3Tools for R410A (The following table shows whether conventional tools can be used or not.)
Tools and materials Use R410A tools Can R22 tools be used?
Gauge manifold Air purge, refrigerant charge and
operation check
Tool exclusive for R410A
Charge hose Tool exclusive for R410A
Gas leak detector Gas leak check Tool for HFC refrigerant
Refrigerant recovery equipment Refrigerant recovery Tool exclusive for R410A
Refrigerant cylinder Refrigerant charge Tool exclusive for R410A
Applied oil Apply to ared section Ester oil and alkylbenzene oil
(minimum amount)
Safety charger Prevent compressor malfunction when
charging refrigerant by spraying liquid
refrigerant
Tool exclusive for R410A
Charge valve Prevent gas from blowing out when
detaching charge hose
Tool exclusive for R410A
Vacuum pump Vacuum drying and air purge Tools for other refrigerants can be
used if equipped with adopter for
reverse ow check
(Usable if equipped with adopter for
reverse ow)
Flare tool Flaring work of piping Tools for other refrigerants can be
used by adjusting aring dimension
(Usable by adjusting aring
dimension)
Bender Bend the pipes
Tools for other refrigerants can be used
Pipe cutter Cut the pipes Tools for other refrigerants can be used
Welder and nitrogen gas cylinder Weld the pipes Tools for other refrigerants can be used
Refrigerant charging scale Refrigerant charge Tools for other refrigerants can be used
Vacuum gauge or thermistor vacuum
gauge and vacuum valve
Check the degree of vacuum. (Vacuum
valve prevents back ow of oil and
refrigerant to thermistor vacuum gauge)
Tools for other refrigerants can be
used
Charging cylinder Refrigerant charge Tool exclusive for R410A
: Prepare a new tool. (Use the new tool as the tool exclusive for R410A.)
: Tools for other refrigerants can be used under certain conditions.
: Tools for other refrigerants can be used.
Flare cutting dimensions
Nominal
dimensions (in)
Outside
diameter (mm)
Dimension A ( + 0
-0.4 )
R410A (in[mm]) R22 (mm)
1/4 6.35 11/32-23/64 [ 9.1] 9.0
3/8 9.52 1/2-33/64 [13.2] 13.0
1/2 12.70 41/64-21/32 [16.6] 16.2
5/8 15.88 49/64-25/32 [19.7] 19.4
3/4 19.05 — 23.3
Flare nut dimensions
Nominal
dimensions (in)
Outside
diameter (mm)
Dimension B
R410A (in[mm]) R22 (mm)
1/4 6.35 43/64 [17.0] 17.0
3/8 9.52 7/8 [22.0] 22.0
1/2 12.70 1-3/64 [26.0] 24.0
5/8 15.88 1-9/64 [29.0] 27.0
3/4 19.05 — 36.0

6
OCH721A
3 FEATURES
HIGH HEATING CAPACITY
High capacity compressor is equipped, which enables to keep
the equal capacity to the rating even when outside temperature
is 5°F [−15°C].
WIDE HEATING RANGE
The heating range is expanded to −13°F [−25°C] compared to
PUZ-A type which is up to 10°F [−12°C].
CHARGELESS SYSTEM
PRE-CHARGED REFRIGERANT IS SUPPLIED FOR PIPING LENGTH AT SHIPMENT.
Maximum 70 ft, 21m
The refrigerant circuit with LEV (Linear Expansion Valve) and power receiver always control the optimal refrigerant level
regardless of the length (maximum: 70 ft [21 m] and minimum: 16 ft [5 m]) of piping. The additional refrigerant charg-
ing work during installation often causes problems. It is completely eliminated by chargeless system. This unique system
improves the quality and reliability of the work done. It also helps to speed up the installation time.
PUZ-HA24NHA
Outdoor W.B. temp.
Heating capacity
-13°F
[-25°C]
-4°F
[-20°C]
5°F
[-15°C]
14°F
[-10°C]
23°F
[-5°C]
32°F
[0°C]
A24
HA24
30,000
(Btu/h)
20,000
16,500Btu/h
26,000Btu/h
0
Performance
about 60%UP
Expanded
Up to -13
°F
Outdoor wet-bulb temperature
A24 type
HA24 type
-13°F
10°F
-13°F
[-25°C]
-4°F
[-20°C]
5°F
[-15°C]
14°F
[-10°C]
23°F
[-5°C]
32°F
[0°C]

7
OCH721A
4 SPECIFICATIONS
Service Ref. PUZ-HA24NHA
Power supply Phase Single
Cycle 60 Hz
Voltage 208/230 V
MCA A 19
MOCP A 26
Breaker size A 25
External nish Munsell 3Y 7.8/1.1
Heat exchanger Plate n coil
Defrost method Reverse cycle
Crankcase heater kW —
Compressor Hermetic
Model DNB28FBAMT
Motor output kW 4.7
R.L.A. 9
L.R.A. 18
Starter type Inverter
Fan Fan(drive) × No. Propeller fan x 1
Fan motor output kW 0.086
Fan motor F.L.A. 0.40
Airow m3/min 55
CFM 1940
Sound pressure level (SPL) Cooling dB 52
Heating dB 53
Protection devices HP switch
Comp. Surface thermistor
Dimensions W mm 950
D mm 330 + 30
H mm 943
W in 37 - 13/32
D in 13 + 1-3/16
H in 37 - 1/8
Weight kg 85
lb 188
Refrigerant R410A
Charged kg 3.5
lb 7 + 11/16
Control Linear expansion valve
Oil Charged Model FVC68D
L 1.0
oz 33
Refrigerant piping Pipe size O.D.
Liquid
mm 9.52
in 3/8
Pipe size O.D.
Gas
mm 15.88
in 5/8
Connection method Indoor Flared
Connection method Outdoor Flared
Height difference
IU-OU
m Maximum 30
ft Maximum 100
Piping length m Maximum 50
ft Maximum 165

8
OCH721A
5-1. REFILLING REFRIGERANT CHARGE (R410A: oz, kg)
Service Ref. Piping length (one way)
PUZ-HA24NHA 50 ft 60 ft 70 ft 80 ft 90 ft 100 ft 110 ft 120 ft 130 ft 140 ft 150 ft 160 ft 165 ft Factory
charged
15 m 18 m 21 m 24 m 27 m 30 m 34 m 37 m 40 m 43 m 46 m 49 m 50 m
123 oz 123 oz 123 oz 130 oz 137 oz 144 oz 151 oz 158 oz 165 oz 172 oz 179 oz 186 oz 190 oz 123 oz
3.5 kg 3.5 kg 3.5 kg 3.7 kg 3.9 kg 4.1 kg 4.3 kg 4.5 kg 4.7 kg 4.9 kg 5.1 kg 5.3 kg 5.4 kg 3.5 kg
5-2. COMPRESSOR TECHNICAL DATA
(Winding resistance at 68°F [20°C])
Service Ref. PUZ-HA24NHA
Compressor model DNB28FBAMT
Winding resistance
(Ω)
U-V 0.74
U-W 0.74
W-V 0.74
5DATA
5-3. NOISE CRITERION CURVES
PUZ-HA24NHA
10
20
30
40
50
60
70
80
90
63 125 250 500 1000 2000 4000 8000
COOLING
MODE
HEATING
52
SPL(dB)
53
LINE
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
5 ft
3.3 ft
MICROPHONE
UNIT
GROUND
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
Additional charge is required for pipes longer than 70 ft.

9
OCH721A
5-4. STANDARD OPERATION DATA
Representative matching PLA-A24EA7
Mode COOLING HEATING
Total Capacity Btu/h 24,000 26,000
Input W 1,710 1,700
Electrical circuit
Indoor unit model PLA-A24EA7
Phase Single
Cycle 60 Hz
Voltage 208/230 V
Current 0.49 A
Outdoor unit model PUZ-HA24NHA
Phase Single
Cycle 60 Hz
Voltage 208/230 V
Current 7.40 A
Refrigerant circuit
Discharge pressure PSIG 383 325
Suction pressure PSIG 145 101
Discharge temperature °F 146 141
Condensing temperature °F 114 98
Suction temperature °F 57 40
Ref. Pipe length ft 25 25
Discharge pressure Mpa 2.64 2.24
Suction pressure Mpa 1 0.7
Discharge temperature °C 63.5 60.5
Condensing temperature °C 45.3 36.7
Suction temperature °C 14 4.4
Ref. Pipe length m 7.6 7.6
Indoor
side
Intake air temperature D.B. °F 80 70
Intake air temperature W.B. °F 67 60
Discharge air temperature D.B. °F 58 100
Outoor
side
Intake air temperature D.B. °F 95 47
Intake air temperature W.B. °F 75 43
Indoor
side
Intake air temperature D.B. °C 26.7 21.1
Intake air temperature W.B. °C 19.4 15.6
Discharge air temperature D.B. °C 14.3 37.5
Outoor
side
Intake air temperature D.B. °C 35 8.3
Intake air temperature W.B. °C 23.9 6.1
SHF 0.86 ―
BF 0.05 ―

10
OCH721A
6OUTLINES AND DIMENSIONS
PUZ-HA24NHA Unit: mm<inch>

11
OCH721A
7WIRING DIAGRAM
PUZ-HA24NHA

12
OCH721A
8WIRING SPECIFICATIONS
8-1. INDOOR UNIT POWER SUPPLIED FROM OUTDOOR UNIT
The following connection patterns are available.
The outdoor unit power supply patterns vary on models.
1:1 System
AOutdoor unit power supply
BEarth leakage breaker
CWiring circuit breaker or isolating switch
DOutdoor unit
EIndoor unit/outdoor unit connecting cords
FRemote controller
GIndoor unit
HIndoor unit earth
S1
S2
L1
L2
GR
1
2
S1
S2
S3
S3
Warning:
In the case of A-control wiring, there is high voltage potential on the S3 terminal caused by electrical circuit design that has no electrical insulation between power
line and communication signal line. Therefore, please turn off the main power supply when servicing. And do not touch the S1, S2, S3 terminals when the power
isenergized. If isolator should be used between indoor unit and outdoor unit, please use 3-pole type.
Affix a label A that is included with the manuals near each wiring diagram for the indoor and outdoor units.
A
D
C
B
E
F
G
H
*1
Maximum 147 ft [45 m]
If AWG13 is used, maximum 164 ft [50 m].
If AWG13 is used and S3 is separated, maximum 262 ft [80 m].
*2
The 30 ft [10 m] wire is attached in the remote controller accessory. Maximum 1500 ft
*3
The figures are NOT always against the ground.
S3 terminal has 24 VDC against S2 terminal. However between S3 and S1, these terminals are NOT electrically insulated by the transformer or other device.
*4
Use earth leakage breaker (NV)
1. Wiring size must comply with the applicable local and national code.
2. Use copper supply wires.
3. Use wires rated 600V or more for the power supply cables and the indoor/outdoor unit connecting cables.
4. Install an earth line longer than power cables.
Notes:
Outdoor unit model
Outdoor unit power supply
Breaker size
Minimum circuit ampacity
Maximum rating of overcurrent protective device
Outdoor unit power supply
Outdoor unit power supply earth
Indoor unit-Outdoor unit
*1
Indoor unit earth
Remote controller-Indoor unit
*2
Outdoor unit L1-L2
*3
Indoor unit-Outdoor unit S1-S2
*3
Indoor unit-Outdoor unit S2-S3
*3
Remote controller-Indoor unit
*3
HA24
Single, 208/230 V, 60 Hz
25 A
19 A
26 A
2 oMin AWG 12
1 oMin AWG 12
3 oAWG 14 (polar)
1 oMin AWG 14
2 o AWG 22 (Non-polar)
208/230 VAC
24 VDC
Wiring
Wire No. o
size
Circuit
rating
S1
S2
S3
S1
S2
S3
A-Control
Outdoor Unit
3 poles isolator
208/230 V
Single phase
Isolator
A-Control
Indoor Unit
*4
• Turn on the main power when the ambient temperature is −4°F [−20°C] or higher.
• In below −4°F [−20°C] condition, it needs at least 4 hr standby to operate in order to warm the electrical parts.
208/230 VAC
12 VDC

13
OCH721A
8-2. SEPARATE INDOOR UNIT/OUTDOOR UNIT POWER SUPPLIES
The following connection patterns are available.
The outdoor unit power supply patterns vary on models.
1:1 System
S1
S2
1
2
S1
S2
S3
S3
Affix a label B that is included with the manuals near each wiring diagram for the indoor and outdoor units.
The optional indoor power supply terminal kit is required. Outdoor unit power supply
Wiring circuit breaker or isolating switch
Outdoor unit
Indoor unit/outdoor unit connecting cords
Remote controller
Indoor unit
Indoor unit power supply
A
Earth leakage breaker
B
C
D
E
F
G
H
Option
J
AJ
D
C
B
E
F
G
HC
B
L1
L2
GR
L1
L2
GR
8-3. INDOOR – OUTDOOR CONNECTING CABLE
Note: The Maximum cable length may vary depending on the condition of installation, humidity or materials, etc.
Indoor unit-Outdoor unit
Outdoor power supply Max. 147 ft [45 m]
3 oAWG15(polar)
Max. 164 ft [50 m]
3 oAWG13(polar)
Max. 262 ft [80 m]
3 oAWG13(polar) and S3 separated
Wire No. oSize
Be sure to connect the indoor-outdoor connecting cables directly to the units (no intermediate connections).
Intermediate connections can lead to communication errors if water enters the cables and causes insufficient
insulation to ground or a poor electrical contact at the intermediate connection point.
Indoor unit-Outdoor unit
Indoor/Outdoor separate
power supply Max. 393 ft [120 m]
2 oMin. AWG22
Wire No. oSize
Note: The optional indoor power supply terminal kit is necessary.

14
OCH721A
8-4. M-NET WIRING METHOD
Points to notice:
(1)
Outside the unit, transmission wires should stay away from electric wires in order to prevent electromagnetic noise from making
an influence on the signal communication. Place them at intervals of more than 5cm. Do not put them in the same conduit tube.
(2) Terminal block (TB7) for transmission wires should never be connected to 208/230 V power supply. If it is connected,
electronic parts on M-NET P.C. board may be burnt out.
(3) Use 2-core x AWG16 [1.25 mm2] shield wire (CVVS, CPEVS) for the transmission wire. Transmission signals may not be
sent or received normally if different types of transmission wires are put together in the same multi-conductor cable. Never
do this because this may cause a malfunction.
It is acceptable if M-NET wire (non-polar, 2-cores) is arranged in addition to the wiring for A-control.
(4) Ground only one of any appliances through M-NET transmission wire (shield wire). Communication error may occur due to
the influence of electromagnetic noise.
“Ed” error will appear on the LED display of outdoor unit.
“0403” error will appear on the centralized remote controller.
If there are more than 2 grounding spots on the shield wire, noise may enter into the shield wire because the ground wire and shield
wire form one circuit and the electric potential difference occurs due to the impedance difference among grounding spots. In the case
of single spot grounding, noise does not enter into the shield wire because the ground wire and shield wire do not form 1 circuit.
To avoid communication errors caused by noise, make sure to observe the single spot grounding method described in the
installation manual.
Centralized
controller
Refrigerant
address 00
M-NET
address 01
A-control
remote
controller
A-control
remote
controller
A-control
remote
controller
Refrigerant
address 00
M-NET
address 02
Refrigerant
address 00
M-NET
address 03
Power
supply unit
Centralized
controller
M-NET transmission wire
O Bad example (Multi spot grounding of shield wire)
Good example 1 (Single spot grounding of shield wire)
Power
supply unit
M-NET type
outdoor unit
M-NET type
outdoor unit
M-NET type
outdoor unit M-NET type outdoor unit
M-NET transmission wire
M-NET type
outdoor unit M-NET type outdoor unit
M-NET type
outdoor unit
M-NET transmission wire
M-NET type
outdoor unit M-NET type outdoor unit
Good example 2 (Single spot grounding of shield wire)
Centralized
controller
Centralized
controller
Power
supply unit
Power
supply unit
●M-NET wiring
(1) Use 2-core x AWG16 [1.25 mm2] shield wire for electric wires.
(Excluding the case connecting to system controller.)
(2) Connect the wire to the M-NET terminal block. Connect one core of the
transmission wire (non-polar) to A terminal and the other to B. Peel the
shield wire, twist the shield part to a string and connect it to S terminal.
(3) In the system which several outdoor units are being connected, the terminal
(A(M1), B(M2), S) on M-NET terminal block should be individually wired to the other
outdoor unit’s terminal, i.e. A to A, B to B and S to S. In this case, choose one of those outdoor units and drive a screw
to fix an ground wire on the plate as shown on the right figure.
Transmission
wire Shield part
M-NET
terminal
block Ground
wire
A B S

15
OCH721A
8-4-3. Regulations in address settings
In the case of multiple grouping system, M-NET and refrigerant address settings should be done as explained in the above
section. Set the lowest number in the group for the outdoor unit whose refrigerant address is “00” as its M-NET address.
Note: Refrigerant addresses can be overlapped if they are in the different group.
Note: In group B, M-NET address of the outdoor unit whose refrigerant address is “00” is not set to the minimum in the
group. As “03” is right for this situation, the setting is wrong. Taking group A as a good sample, set the minimum M-NET
address in the group for the outdoor unit whose refrigerant address is “00”.
8-4-1. M-NET address setting
In A-control models, M-NET address and refrigerant address should be set only for the outdoor unit. Similar to CITY MULTI
series, there is no need to set the address of outdoor unit and remote controller. To construct a central control system, the
setting of M-NET address should be conducted only upon the outdoor unit. The setting range should be 1 to 50 (the same as
that of the indoor unit in CITY MULTI system), and the address number should be consecutively set in a same group.
Address number can be set by using rotary switches
(SW11 for ones digit and SW12 for tens digit), which
is located on the M-NET board of outdoor unit.
(Initial setting: all addresses are set to “0”.)
8-4-2. Refrigerant address setting
In the case of multiple grouping system (multiple refrigerant circuits in one group), indoor units should be connected by
remote controller wiring (TB5) and the refrigerant address needs to be set. Leave the refrigerant addresses to “00” if the
group setting is not conducted. Set the refrigerant address by using DIP SW1-3 to 1-6 on the outdoor controller board. [Initial
setting: all switches are OFF. (All refrigerant addresses are “00”.)]
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1 2
–
50
M-NET Address No. <Setting example>
Switching
setting
SW11
ones
digit
SW12
tens
digit
OFF
ON
123456123456123456123456123456123456123456123456
123456 123456 123456 123456 123456 123456 123456 123456
0
Refrigerant
address
OFF
ON
8
OFF
ON
1
OFF
ON
9
OFF
ON
10
OFF
ON
11
OFF
ON
12
OFF
ON
13
OFF
ON
14
OFF
ON
15
OFF
ON
2
OFF
ON
3
OFF
ON
4
OFF
ON
5
OFF
ON
6
OFF
ON
7
A-control
remote
controller
Group A Group B Group C
A-control
remote
controller
TB5
A-control
remote
controller
Refrigerant
address 00
M-NET
address 01
Refrigerant
address 00
M-NET
address 02
Refrigerant
address 01
M-NET
address 03
Refrigerant
address 00
M-NET
address 04
Power
supply unit
Centralized
controller
Power
supply unit
A-control
remote
controller
A-control
remote
controller
TB5
Group A Group B
Refrigerant
address 00
M-NET
address 01
Refrigerant
address 01
M-NET
address 02
Refrigerant
address 00
M-NET
address 04
Refrigerant
address 01
M-NET
address 03
Refrigerant
address 02
M-NET
address 05
Centralized
controller

16
OCH721A
9REFRIGERANT SYSTEM DIAGRAM
PUZ-HA24NHA Unit: mm (in)
Distributor
Thermistor TH7
(Ambient)
Heat exchanger
Refrigerant
GAS pipe
connection
[15.88(5/8)
Refrigerant
LIQUID pipe
connection
[9.52
(3/8) Stop valve
(with service port)
Strainer
(#100)
Power
receiver
Linear
expansion valve-B
Linear expansion valve-A
Thermistor
TH6
(2-phase pipe)
Thermistor TH3
(Liquid)
Charge plug
(Low pressure)
Charge plug
(High pressure)
Thermistor TH4
(Discharge)
Compressor
Strainer
(#50)
Solenoid valve
(4-way valve)
Strainer
(#100)
Strainer
(#100)
Strainer
(#100)
Muffler
Ball valve
Thermistor TH33
(Comp. surface)
High pressure
switch 63H
Refrigerant flow in cooling
Refrigerant flow in heating
Thermistor TH8
(Heat sink)
Power circuit board
REFRIGERANT COLLECTING (PUMP DOWN)
When relocating or disposing of the indoor/outdoor unit, pump down the system following the procedures below so that no refrig-
erant is released into the atmosphere.
1 Turn o󰀨 the power supply (circuit breaker).
2Connect the low pressure valve on the gauge manifold to the charge plug (low pressure side) on the outdoor unit.
3Close the liquid stop valve completely.
4Supply power (circuit breaker).
• When power is supplied, make sure that “CENTRALLY CONTROLLED” is not displayed on the remote controller. If “CEN-
TRALLY CONTROLLED” is displayed, the refrigerant collecting (pump down) cannot be completed normally.
• Startup of the indoor-outdoor communication takes about 3 minutes after the power (circuit breaker) is turned on. Start the
pump-down operation 3 to 4 minutes after the power (circuit breaker) is turned on.
5Perform the refrigerant collecting operation (cooling test run).
• Push the pump-down SWP switch (push-button type) on the control board of the outdoor unit. The compressor and ventilators
(indoor and outdoor units) start operating (refrigerant collecting operation begins). (LED1 and LED2 on the control board of
the outdoor unit are lit.)
• Only push the pump-down SWP switch if the unit is stopped. However, even if the unit is stopped and the pump-down SWP
switch is pushed less than 3 minutes after the compressor stops, the refrigerant collecting operation cannot be performed.
Wait until the compressor has been stopped for 3 minutes and then push the pump-down SWP switch again.
6Fully close the ball valve on the gas pipe side of the outdoor unit when the pressure gauge on the gauge manifold shows 0.05
to 0 MPa [Gauge] (approx. 0.5 to 0 kgf/cm²) and quickly stop the air conditioner.
• Because the unit stops automatically in about 3 minutes when the refrigerant collecting operation is completed (LED1 o󰀨,
LED2 lit), be sure to quickly close the gas ball valve. However, if LED1 is lit, LED2 is o󰀨, and the unit is stopped, open the
liquid stop valve completely, close the valve completely after 3 minutes or more have passed, and then repeat step 5. (Open
the gas ball valve completely.)
• If the refrigerant collecting operation has been completed normally (LED1 o󰀨, LED2 lit), the unit will remain stopped until the
power supply is turned o󰀨.
• Note that when the extension piping is very long with a large refrigerant amount, it may not be possible to perform a pump-
down operation. In this case, use refrigerant recovery equipment to collect all of the refrigerant in the system.
7 Turn o󰀨 the power supply (circuit breaker), remove the gauge manifold, and then disconnect the refrigerant pipes.
Warning:
When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes.
•
If the refrigerant pipes are disconnected while the compressor is operating and the stop valve (ball valve) is open, the pressure
in the refrigeration cycle could become extremely high if air is drawn in, causing the pipes to burst, personal injury, etc.

17
OCH721A
10 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.
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 “10-4. SELF-DIAGNOSIS ACTION TABLE”.
Not displayed
Conduct troubleshooting and ascertain the cause of the
trouble according to “10-5. TROUBLESHOOTING BY
INFERIOR PHENOMENA”.
The trouble is not reoccurring.
Logged
1 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.
2 Reset check code logs and restart the unit after finishing
service.
3 There is no abnormality in electrical component, controller
board, remote controller, etc.
Not logged
1Re-check the abnormal symptom.
2 Conduct troubleshooting and ascertain the cause of the
trouble according to “10-5. TROUBLESHOOTING BY
INFERIOR PHENOMENA”.
3 Continue to operate unit for the time being if the cause is
not ascertained.
4 There is no abnormality concerning of parts such as
electrical component, controller board, remote controller,
etc.
10-1. TROUBLESHOOTING
10-2. CHECK POINT UNDER TEST RUN
(1) Before test run
• After installation of indoor and outdoor units, piping work and electric wiring work, re-check that there is no refrigerant leak-
age, loosened connections and incorrect polarity.
• Measure impedance between the ground and the power supply terminal block (L1, L2) on the outdoor unit by 500 V Megger
and check that it is 1.0 M"or over.
Note: Do not use 500 V Megger to indoor/outdoor connecting wire terminal block (S1, S2, S3) and remote controller terminal
block (1, 2). This may cause malfunction.
• Make sure that test run switch (SW4) is set to OFF before turning on power supply.
• Turn on power supply 12 hours before test run in order to protect compressor.
• For specific models which requires higher ceiling settings or auto-recovery feature from power failure, make proper changes
of settings referring to the description of “12. FUNCTION SETTING".
Make sure to read operation manual before test run. (Especially items to secure safety.)

18
OCH721A
F1 F2 F3 F4
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Test run
Input maintenance info.
Function setting
Check
Self check
10-2-1. Test run for wired remote controller <PAR-4xMAA, PAR-3xMAA ("x" represents 0 or later)>
PAR-4xMAA
PAR-4x/3xMAA
PAR-3xMAA
PAR-4x/3xMAA
PAR-4x/3xMAA
MENU ON
OFF
RETURN SELECT
HOLD
F1 F2 F3 F4
Test run menu
Cursor
Service menu: MENU
Test run
Drain pump test run
1Select "Service" from the Main menu, and press the [SELECT] button.
2Select "Test run" with the F1 or F2 button, and press the [SELECT] button.
Select "Test run" with the
F1
or
F2
button, and press
the [
SELECT] button.
F1 F2 F3 F4
Cool
Pipe
Auto
Switch disp.
Mode Fan
RemainTest run
Remain
Vane
Test run
F1 F2 F3 F4
MENU
ON
OFF
RETURN SELECT
HOLD
Cool mode: Check the cold air blows out.
Heat mode: Check the heat blows out.
Press the F1 button to go through the operation modes in the order of "Cool
and Heat".
Check the auto vane with the F1 F2 buttons.
Press the [RETURN] button to return to “Test run operation”.
Press the [ON/OFF] button.
When the test run is completed, the “Test run menu” screen will appear.
The test run will automatically stop after 2 hours.
Test run operation
Auto vane check
Press the [SELECT] button and open the Vane setting screen.
Function buttons
F1 F2 F3 F4
MENU RETURN SELECT ON/OFF
Check the operation of the outdoor unit’s fan.
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Test run
Input maintenance info.
Settings
Check
Others
F1 F2 F3 F4
MENU
ON
OFF
RETURN SELECT
HOLD
F1 F2 F3 F4
MENU
ON
OFF
RETURN SELECT
HOLD
F1 F2 F3 F4
MENU
ON
OFF
RETURN SELECT
HOLD

19
OCH721A
Error information
Error code
Error unit IU
Ref. address Unt#
Model name
Serial No.
ResetPage
Reset error: Reset button
Error information
Error code
Error unit IU
Ref. address Unt#
Model name
Serial No.
ResetPage
Reset error: Reset button
PAR-4xMAA PAR-3xMAA
PAR-4xMAA PAR-3xMAA
PAR-4x/3xMAA
PAR-4x/3xMAA
PAR-4x/3xMAA
Error information
Error code A3
Error unit IU
Time Occurred
Model name
Serial No.
ResetPage
2 / 1
Unit#1
4:48
Reset error: Reset button
Error information
Error code A3
Error unit IU
Time Occurred
Model name
Serial No.
ResetPage
2 / 1
Unit#1
4:48
Reset error: Reset button
Error information
Contact information
Dealer
Tel
ResetPage
Reset error: Reset button
Error reset
Error reset
Main menu: MENU
Error reset
Reset current error?
OKCancel
F1 F2 F3 F4
1Check code, error unit, refrigerant address, unit model name, and
serial number will appear. (Date and time of occurrence of the er-
ror will also appear on PAR-4xMAA.)
The model name and serial number will appear only if the informa-
tion has been registered.
Press the F1 or F2 button to go to the next page.
When an error occurs, the following screen will appear.
Check the error status, stop the operation, and consult your dealer.
Contact information (dealer's phone number) will appear if
the information has been registered.
2Press the F4 button or the [ON/OFF] button to reset the
error that is occurring.
Errors cannot be reset while the ON/OFF operation is prohibited.
Select "OK" with the F4 button.
Navigating through the screens
• To go back to the Main menu .......... [MENU] button
<Error information>
blinks
F1 F2 F3 F4
MENU
ON
OFF
RETURN SELECT
HOLD
blinks
F1 F2 F3 F4
MENU
ON
OFF
RETURN SELECT
HOLD

20
OCH721A
Main
Main display:
Cursor Page
Main menu
Restriction
Energy saving
Night setback
Filter information
Error information
F1 F2 F3 F4
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Test run
Input maintenance info.
Function setting
Check
Self check
F1 F2 F3 F4
Check menu
Cursor
Service menu:
Error history
Refrigerant volume check
Refrigerant leak check
Smooth maintenance
Request code
PAR-4xMAA
PAR-4xMAA
PAR-4xMAA
PAR-3xMAA
PAR-3xMAA
PAR-3xMAA
PAR-4x/3xMAA
PAR-4x/3xMAA
Main menu: RETURN
Cursor
Maintenance menu
Error information
Filter information
Cleaning
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Test run
Input maintenance info.
Settings
Check
Others
While no errors are occurring, page 2/2 of the error information
can be viewed by selecting "Error information" from the Mainte-
nance menu (PAR-4xMAA) or Main menu (PAR-3xMAA).
Errors cannot be reset from this screen.
<Checking the error information>
<Error history>
F1 F2 F3 F4
Check menu
Cursor
Service menu: MENU
Error history
Diagnosis
Smooth maintenance
Request code
F1 F2 F3 F4
Error history
Page Delete
Check menu: RETURN
Error Unt# dd/ mm /yy
Error history
Cancel OK
Delete error history?
Error history
Check menu: RETURN
Error history deleted
2Select "Error history" with the F1 or F2 button, and press
the [SELECT] button.
Select "Check" with the F1 or F2 button, and press the
[SELECT] button.
3Select "Error history" from the Check menu, and press the [SELECT] button to
view up to 16 error history records.
4 records are shown per page, and the top record on the rst page indicates
the latest error record.
Error history
4To delete the error history, press the F4 button (Delete) on the screen that
shows error history.
A conrmation screen will appear asking if you want to delete the error history.
Press the F4 button (OK) to delete the history.
"Error history deleted" will appear on the screen.
Press the [RETURN] button to go back to the Check menu screen.
Deleting the error history
1Select "Service" from the Main menu, and press the
[SELECT] button.
F1 F2 F3 F4
MENU
ON
OFF
RETURN SELECT
HOLD
F1 F2 F3 F4
MENU
ON
OFF
RETURN SELECT
HOLD
F1 F2 F3 F4
MENU
ON
OFF
RETURN SELECT
HOLD