Mitsubishi Electric MSZ-WR18NA User manual

Outdoor unit service manual
MUZ-WR•NA Series (OBH819)
PARTS CATALOG (OBB818)
MSZ-WR24NA
INDOOR UNIT
SERVICE MANUAL
INDOOR UNIT
Models
MSZ-WR09NA -U1
MSZ-WR12NA -U1
MSZ-WR18NA -U1
MSZ-WR24NA -U1
CONTENTS
1. TECHNICAL CHANGES································ 2
2. PART NAMES AND FUNCTIONS··················3
3. SPECIFICATION ········································5
4. OUTLINES AND DIMENSIONS·····················7
5. WIRING DIAGRAM·····································8
6. REFRIGERANT SYSTEM DIAGRAM·············9
7. SERVICE FUNCTIONS······························10
8. MICROPROCESSOR CONTROL ················12
9. TROUBLESHOOTING·······························16
10. DISASSEMBLY INSTRUCTIONS·················30
No. OBH818

2
1TECHNICAL CHANGES
MSZ-WR09NA - U1
MSZ-WR12NA - U1
MSZ-WR18NA - U1
MSZ-WR24NA - U1
1. New model
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.
OBH818

3
2PART NAMES AND FUNCTIONS
MSZ-WR09NA MSZ-WR12NA
Operation indicator lamp
Remote control receiving section
Emergency operation switch
Horizontal vane
Air outlet
Air ¿lter
Air inlet
Heat exchanger
Front panel
Air cleaning ¿lter
(Anti-Allergy Enzyme
Filter, option)
Display section Remote controller
ACCESSORIES
Installation plate 1
Attachment screws for the installation plate
4 × 25 mm 5
Battery (AAA) for remote controller 2
Wireless remote controller 1
Felt tape (For left or left-rear piping) 1
OBH818

4
MSZ-WR18NA MSZ-WR24NA
ACCESSORIES
Installation plate 1
Attachment screws for the installation
plate 4 × 25 mm 5
Wireless remote controller 1
Felt tape (For left or left-rear piping) 1
Battery (AAA) for remote controller 2
Remote controller
Operation indicator lamp
Remote control receiving section
Emergency operation switch
Horizontal vane
Air outlet
Air ¿lter
Air inlet
Heat exchanger
Front panel
Air cleaning ¿lter
(Anti-Allergy Enzyme
Filter, option)
Display section
OBH818

5
3SPECIFICATION
Indoor model MSZ-WR18NA MSZ-WR24NA
Power supply V, phase, Hz 208/230, 1, 60
Max. fuse size (time delay)/ Disconnect switch A15
Min. circuit ampacity A 1.0
Fan motor F.L.A 0.67
Airflow
Super High - High - Med. - Low
COOL Dry
(Wet)
CFM 625 - 530 - 431 - 328
(562 - 477 - 388 - 295)
702 - 530 - 431 - 353
(632 - 477 - 388 - 318)
HEAT Dry CFM 625 - 530 - 431 - 307 702 - 579 - 448 - 346
Moisture removal pt./h 2.1 2.3
Sound level
Super High - High - Med. - Low
Cooling dB(A) 47 - 42 - 37 - 30 50 - 44 - 38 - 33
Heating dB(A) 47 - 42 - 37 - 30 50 - 44 - 38 - 32
Fan speed
Super High - High - Med. - Low
Cooling rpm 1,140 - 1,000 - 850 - 690 1,250 - 1,000 - 850 - 730
Heating rpm 1,140 - 1,000 - 850 - 660 1,250 - 1,070 - 880 - 720
Cond. drain connection O.D. in. 5/8
Dimensions
W
in.
36-5/16
D 9-13/16
H12
Weight Ib. 28
External finish Munsell 1.0Y 9.2/0.2
Control voltage (by built-in transformer) 12 - 24 V DC
NOTE: Test conditions are based on AHRI 210/240.
Indoor model MSZ-WR09NA MSZ-WR12NA
Power supply V, phase, Hz 208/230, 1, 60
Max. fuse size (time delay)/ Disconnect switch A15
Min. circuit ampacity A 1.0
Fan motor F.L.A 0.76
Airflow
Super High - High - Med. - Low
COOL Dry
(Wet)
CFM 399 - 321 - 237 - 170
(364 - 286 - 201 - 134)
HEAT Dry CFM 406 - 321 - 237 - 170
Moisture removal pt./h 1.5 2.5
Sound level
Super High - High - Med. - Low
Cooling dB(A) 43 - 37 - 30 - 22 45 - 37 - 30 - 22
Heating dB(A) 43 - 37 - 30 - 22
Fan speed
Super High - High - Med. - Low
Cooling rpm 1,020 - 860 - 670 - 530
Heating rpm 1,040 - 860 - 670 - 530
Cond. drain connection O.D. in. 5/8
Dimensions
W
in.
31-7/16
D 9-1/8
H 11-5/8
Weight Ib. 22
External finish Munsell 1.0Y 9.2/0.2
Control voltage (by built-in transformer) 12 - 24 V DC
NOTE: Test conditions are based on AHRI 210/240.
OBH818

6
(2) OPERATION
Mode Condition
Intake air temperature (°F)
Indoor Outdoor
DB WB DB WB
Cooling
Standard temperature 80 67 95 —
Maximum temperature 90 73 115 —
Minimum temperature 67 57 14 —
Maximum humidity 78% —
Heating
Standard temperature 70 60 47 43
Maximum temperature 80 67 75 65
Minimum temperature 70 60 -4 -5
3-1. OPERATING RANGE
(1) POWER SUPPLY
Rated voltage Guaranteed voltage (V)
Indoor unit
208/230 V
1 phase
60 Hz
Min. 187 208 230 Max. 253
3-2. OUTLET AIR SPEED AND COVERAGE
●The air coverage is the figure up to the
position where the air speed is 1 ft./s.,
when air is blown out horizontally from
the unit properly at the High speed posi-
tion.
The coverage should be used only as a
general guideline since it varies accord-
ing to the size of the room and furniture
arranged inside the room.
Model Mode Function Airflow
(CFM)
Air speed
(ft./s.)
Coverage
(ft.)
MSZ-WR09NA
HEAT Dry 406 20.6 29.5
COOL Dry 321 16.3 23.5
Wet 286 14.5 21.0
MSZ-WR12NA
HEAT Dry 406 20.6 29.5
COOL Dry 321 16.3 23.5
Wet 286 14.5 21.0
MSZ-WR18NA
HEAT Dry 625 28.5 42.6
COOL Dry 625 28.5 42.6
Wet 562 25.6 38.4
MSZ-WR24NA
HEAT Dry 702 32.0 47.7
COOL Dry 702 32.0 47.7
Wet 632 28.8 43.1
OBH818

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Unit: inch
MSZ-WR09NA MSZ-WR12NA
MSZ-WR18NA MSZ-WR24NA
4OUTLINES AND DIMENSIONS
Piping
Insulation
MSZ-WR24NA
Ø2 O.D
Liquid line Ø5/16 15-3/8 (Flared connection Ø3/8)
Gas line Ø15/32 13-3/8 (Flared connection Ø5/8)
Drain hose Insulation Ø1-1/8 Connected part Ø5/8 O.D
Piping
Insulation
MSZ-WR18NA
Ø2 O.D
Liquid line Ø5/16 15-3/8 (Flared connection Ø1/4)
Gas line Ø15/32 13-3/8 (Flared connection Ø1/2)
Drain hose Insulation Ø1-1/8 Connected part Ø5/8 O.D
11/16
5-1/2
2-1/4
2-1/4
2-1/2
9-13/16
3/16
35-13/16
36-5/16
1/4
27-15/16 6-5/16
2-1/16
12
2-9/16
2-13/16
2-1/2
2-9/16
3-11/16
2-1/16
9-7/16
10-5/16
1/8
8-7/8 8-7/8 3-11/16
8-3/4
10-3/8
2-5/16 15-7/8
8-11/16
3-11/16
7/8
1×7/16 Oblong hole
7/16×13/16
Oblong hole
Installation plate
Indoor unit
Wall hole Ø3
Air in
Installation plate
8-1/16
15-3/16
1-5/8
8-11/16
3
1-11/16
2-9/16
2-9/16
4-1/2
5-3/4
1/4
Air out
Piping
Drain hose
3-15/16
11/16
5-1/2
2-1/4
Piping
Insulation ø1 - 3/8 O.D
Liquid line ø1/4 19 - 11/16 (Flared connection ø1/4)
Gas line ø3/8 16 - 15/16
(Flared connection: ø3/8
Drain hose Insulation ø1-1/8 O.D Connected part ø5/8 O.D
OBH818

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MSZ-WR18NA MSZ-WR24NA
5WIRING DIAGRAM
MSZ-WR09NA MSZ-WR12NA
OBH818

9
MSZ-WR18NA MSZ-WR24NA
Unit: inch (mm)
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Flared connection
Refrigerant pipe ø1/2 (ø12.7) (MSZ-WR18NA)
ø5/8 (ø15.88) (MSZ-WR24NA)
(with heat insulator)
Refrigerant pipe ø1/4 (ø6.35) (MSZ-WR18NA)
ø3/8 (ø9.52) (MSZ-WR24NA)
(with heat insulator)
Indoor coil
thermistor
RT12 (main)
Indoor coil
thermistor
RT13 (sub)
Refrigerant flow in cooling
Refrigerant flow in heating
6REFRIGERANT SYSTEM DIAGRAM
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Flared connection
Refrigerant pipe ø3/8 (ø9.52)
(with heat insulator)
Refrigerant pipe ø1/4 (ø6.35)
(with heat insulator)
Indoor coil
thermistor
RT12 (main)
Indoor coil
thermistor
RT13 (sub)
Refrigerant flow in cooling
Refrigerant flow in heating
MSZ-WR09NA MSZ-WR12NA
OBH818

10
7-1. TIMER SHORT MODE
For service, the set time can be shortened by bridging of the timer short point on the indoor electronic control P.C. board.
The time will be shortened as follows. (Refer to 9-7.)
• The set time for the ON/OFF timer can be reduced to 1 second for each minute.
• After the breaker is turned on, the time for starting the compressor, which normally takes 3 minutes, can be reduced to
3 seconds. Restarting the compressor, which takes 3 minutes, cannot be reduced.
7-2. REMOTE CONTROLLER P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION
A maximum of 4 indoor units with wireless remote controllers can be used in a room.
In this case, to operate each indoor unit individually by each remote controller, the remote controller P.C. boards must be
modified according to the number of the indoor unit.
How to modify the remote controller P.C. board
Remove batteries before modification.
The board has a print as shown below:
7SERVICE FUNCTIONS
MSZ-WR09NA MSZ-WR12NA MSZ-WR18NA MSZ-WR24NA
J2
J1
The remote controller P.C. board has the print “J1” and “J2”. Solder “J1” and “J2” according to the number of indoor unit as
shown in Table 1.
After modification, press the RESET button.
NOTE: For modification, take out the
batteries and press the STOP/
OPERATE (OFF/ON) button 2
or 3 times at first.
After finish modification, put
back the batteries then press
the RESET button.
Table 1
1 unit operation 2 units operation 3 units operation 4 units operation
No. 1 unit No modification Same as at left Same as at left Same as at left
No. 2 unit — Solder J1 Same as at left Same as at left
No. 3 unit — — Solder J2 Same as at left
No. 4 unit — — — Solder both J1 and J2
How to set the remote controller exclusively for particular indoor unit
After you turn the breaker ON, the first remote controller that sends the signal to the indoor unit will be regarded as the remote
controller for the indoor unit.
The indoor unit will only accept the signal from the remote controller that has been assigned to the indoor unit once they are
set.
The setting will be cancelled if the breaker is turned OFF, or the power supply is shut down.
Please conduct the above setting once again after the power has been restored.
OBH818