Mitsubishi Electric MUZ-WR-NA Series 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 ,U2
MSZ-WR12NA -U1 ,U2
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···········10
7. SERVICE FUNCTIONS······························11
8. MICROPROCESSOR CONTROL ················13
9. TROUBLESHOOTING·······························17
10. DISASSEMBLY INSTRUCTIONS·················32
No. OBH818
REVISED EDITION-C
OBH818 REVISED EDITION-B is void.
Revision C:
• MSZ-WR09/12NA - U2 have been added.

2
1TECHNICAL CHANGES
MSZ-WR09NA - U1
MSZ-WR12NA - U1
MSZ-WR18NA - U1
MSZ-WR24NA - U1
1. New model
MSZ-WR09NA - U1 MSZ-WR09NA - U2
MSZ-WR12NA - U1 MSZ-WR12NA - U2
1. Indoor electronic control P.C. board and indoor power P.C. board have been changed.
Revision A:
• 3. SPECIFICATION has been corrected.
Use the specied 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.
<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 and pull the power plug.
Discharge the capacitor 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 refrigeration 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.
WARNING
• When the refrigeration circuit has a leak, do not execute pump down with the compressor.
• When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes.
The compressor may burst if air etc. get into it.
• 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.
Revision B:
• 9-7. TEST POINT DIAGRAM AND VOLTAGE has been modified.
Revision C:
• MSZ-WR09/12NA - U2 have been added.
OBH818C

3
2PART NAMES AND FUNCTIONS
MSZ-WR09NA MSZ-WR12NA
Operation indicator lamp
Remote control receiving section
Emergency operation switch
Horizontal vane
Air outlet
Air filter
Air inlet
Heat exchanger
Front panel
Air cleaning filter
(Anti-Allergy Enzyme
Filter, option)
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
OBH818C

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 filter
Air inlet
Heat exchanger
Front panel
Air cleaning filter
(Anti-Allergy Enzyme
Filter, option)
OBH818C

5
3SPECIFICATION
Indoor model MSZ-WR18NA MSZ-WR24NA
Power supply V, phase, Hz 208/230, 1, 60
Max. fuse size (time delay)/ Disconnect switch A 15
Min. circuit ampacity A 1.0
Fan motor F.L.A 0.67
Airow
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 Win. 36-5/16 D 9-13/16
H 12
Weight Ib. 28
External nish 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 A 15
Min. circuit ampacity A 1.0
Fan motor F.L.A 0.76
Airow
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 Win. 31-7/16 D 9-1/8
H 11-5/8
Weight Ib. 22
External nish 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.
OBH818C

6
(2) OPERATION
Mode Condition Intake air temperature (°F)
DB WB
Cooling
Standard temperature 80 67
Maximum temperature 90 73
Minimum temperature 67 57
Maximum humidity 78%
Heating Standard temperature 70 60 Maximum temperature 80 67
Minimum temperature 70 60
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 Airow
(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
OBH818C

7
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
OBH818C

8
5WIRING DIAGRAM
MSZ-WR09NA -U1 MSZ-WR12NA -U1
MSZ-WR09NA -U2 MSZ-WR12NA -U2
OBH818C

9
MSZ-WR18NA MSZ-WR24NA
OBH818C

10
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)
(with heat insulator) ø5/8 (ø15.88) (MSZ-WR24NA)
Refrigerant pipe ø1/4 (ø6.35) (MSZ-WR18NA)
(with heat insulator) ø3/8 (ø9.52) (MSZ-WR24NA)
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
OBH818C