Mitsubishi Electric MSZ-WR NA Series Service Manual
  1. Manuals
  2. Brands
  3. Mitsubishi Electric Manuals
  4. Air Conditioner
  5. MSZ-WR NA Series
  6. Service manual

Mitsubishi Electric MSZ-WR NA Series Service Manual

Hide thumbs

Advertisement

Table of Contents

OUTDOOR UNIT
SERVICE MANUAL
Models
MUZ-WR09NA
MUZ-WR12NA
MUZ-WR18NA
MUZ-WR24NA
MUZ-WR24NA
HFC
utilized
R410A
-
U1
-
U1
-
U1
-
U1
CONTENTS
1. TECHNICAL CHANGES ······························2
2. PART NAMES AND FUNCTIONS ··················3
3. SPECIFICATION ········································4
4. OUTLINES AND DIMENSIONS ·····················7
5. WIRING DIAGRAM ·····································9
6. REFRIGERANT SYSTEM DIAGRAM ··········· 11
7. DATA······················································ 14
8. ACTUATOR CONTROL ····························· 24
9. SERVICE FUNCTIONS ······························ 25
10. TROUBLESHOOTING ······························· 26
11. DISASSEMBLY INSTRUCTIONS ················· 50
PARTS CATALOG (OBB819)
Revision A:
• 7. DATA has been corrected.
OBH819 is void.
No. OBH819
REVISED EDITION-A
Indoor unit service manual
MSZ-WR•NA Series (OBH818)

Advertisement

Table of Contents
loading

Related Manuals for Mitsubishi Electric MSZ-WR NA Series

Summary of Contents for Mitsubishi Electric MSZ-WR NA Series

  • Page 1: Table Of Contents

    Revision A: • 7. DATA has been corrected. OBH819 is void. OUTDOOR UNIT No. OBH819 REVISED EDITION-A utilized SERVICE MANUAL R410A Models MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA MUZ-WR24NA Indoor unit service manual MSZ-WR•NA Series (OBH818) CONTENTS 1. TECHNICAL CHANGES ······························2 2. PART NAMES AND FUNCTIONS ··················3 3.

  • Page 2: Technical Changes

    Use the specifi 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.

  • Page 3: Part Names And Functions

    PART NAMES AND FUNCTIONS MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA Air inlet (back and side) Piping Air outlet Drain hose Drain outlet MUZ-WR24NA Air inlet (back and side) Piping Drain hose Air outlet Drain outlet OBH819A...

  • Page 4: Specification

    SPECIFICATION Outdoor unit model MUZ-WR09NA MUZ-WR12NA Btu/h 9,000 ( 3,800 - 10,000 ) 12,000 ( 3,800 - 12,200 ) Cooling 1 Capacity Rated (Minimum~Maximum) Btu/h 10,900 ( 4,500 - 11,800 ) 12,200 ( 4,500 - 14,500 ) Heating 47 1 Capacity Btu/h 6,700 (7,200)
  • Page 5 Outdoor unit model MUZ-WR18NA MUZ-WR24NA Btu/h 17,200 (5,800 - 18,000) 22,500 (5,800 - 22,500) Cooling 1 Capacity Rated (Minimum~Maximum) Btu/h 18,000 (5,400 - 20,900) 26,000 (5,400 - 26,000) Heating 47 1 Capacity Btu/h 11,500 (15,000) 18,500 (18,500) Heating 17 2 Rated (Maximum) 1,720 (350 - 2,170) 2,810 (330 - 2,810)
  • Page 6 Test condition 3, 4 Indoor air condition (°F) Outdoor air condition (°F) Mode Test Dry bulb Wet bulb Dry bulb Wet bulb "A-2" Cooling steady tate (75) at rated compressor speed "B-2" Cooling steady state (65) at rated compressor speed SEER "B-1"...

  • Page 7: Outlines And Dimensions

    OUTLINES AND DIMENSIONS MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA Unit: inch REQUIRED SPACE 4 in. (100 mm) or more when front and sides of the unit are clear When any 2 sides of left, right and rear of the unit are clear holes Liquid refrigerant pipe joint Refrigerant pipe (flared) Ø...
  • Page 8 MUZ-WR24NA Unit: inch REQUIRED SPACE *1 20 in. (500 mm) or more when front and sides of the unit are clear 16-7/16 Air in 1-9/16 Air in Air out 2-holes 13/32 13/16 19-11/16 6-7/8 *2 When any 2 sides of left, right and rear of the unit are clear 3-3/16 33-1/16...

  • Page 9: Wiring Diagram

    WIRING DIAGRAM MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA OBH819A...
  • Page 10 MUZ-WR24NA OBH819A...

  • Page 11: Refrigerant System Diagram

    REFRIGERANT SYSTEM DIAGRAM MUZ-WR09NA MUZ-WR12NA Unit: Inch (mm) Refrigerant pipe ø3/8 (ø9.52) 4-way valve (with heat insulator) Muffler Outdoor heat exchanger Stop valve temperature (with service port) thermistor Outdoor Muffler Discharge RT68 heat Flared connection temperature exchanger thermistor Service port RT62 Ambient Compressor...
  • Page 12 MUZ-WR24NA Unit: Inch (mm) Muffler 4-way with #100 mesh strainer Refrigerant pipe ø5/8 ( ø 15.88) valve (with heat insulator) Service port Outdoor heat Stop valve exchanger (with service port) temperature Outdoor Flared connection Discharge heat thermistor temperature exchanger RT68 Service thermistor port...
  • Page 13 MAX. REFRIGERANT PIPING LENGTH and MAX. HEIGHT DIFFERENCE Refrigerant piping: ft. Piping size O.D: in. Model Max. Length Max. Height difference Liquid MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA MUZ-WR24NA Indoor unit Max. Height difference Max. Length Outdoor unit ADDITIONAL REFRIGERANT CHARGE (R410A: oz.) NOTE: Refrigerant piping exceeding 25 ft.

  • Page 14: Data

    DATA MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA MUZ-WR24NA 7-1. PERFORMANCE DATA 1) COOLING CAPACITY Indoor air Outdoor intake air DB temperature (˚F) Model IWB (˚F) SHC TPC SHC TPC SHC TPC SHC TPC SHC TPC 11.0 0.73 10.3 0.80 0.86 0.91 0.94 MUZ-WR09NA 10.4 0.69 0.76...
  • Page 15 3) HEATING CAPACITY CORRECTIONS Refrigerant piping length (one way: ft.) Model 25 (std.) MUZ-WR09NA 0.997 0.993 — MUZ-WR12NA MUZ-WR18NA 0.997 0.993 0.987 MUZ-WR24NA 4) HEATING CAPACITY Indoor air Outdoor intake air WB temperature (˚F) Model IDB (˚F) 0.58 0.73 0.86 0.96 10.6 1.00...
  • Page 16 7-2. PERFORMANCE CURVE Cooling Cooling capacity (at Rated frequency) Indoor intake air Wet-bulb temperature( F) Outdoor intake air DB temperature(°F) MUZ-WR09NA MUZ-WR12NA SHF at rating condition = 0.82 SHF at rating condition = 0.77 = 399 CFM = 399 CFM Airflow Airflow Outdoor intake air DB temperature (°F)
  • Page 17 Heating Heating capacity (at Rated frequency) Outdoor intake air WB temperature (°F) MUZ-WR09NA MUZ-WR12NA = 406 CFM = 406 CFM Airflow Airflow Outdoor intake air WB temperature (°F) Outdoor intake air WB temperature (°F) MUZ-WR18NA MUZ-WR24NA = 625 CFM = 702 CFM Airflow Airflow Outdoor intake air WB temperature (°F)
  • Page 18 7-3. CONDENSING PRESSURE Cooling Data is based on the condition of indoor humidity 50 %. Air flow should be set to High speed. MUZ-WR09NA (PSIG) (PSIG) 68 70 100 105 (°F) 68 70 100 105 (°F) Outdoor ambient temperature Outdoor ambient temperature MUZ-WR12NA (PSIG) (PSIG)
  • Page 19 MUZ-WR18NA (PSIG) (PSIG) (°F) (°F) 100 105 Outdoor ambient temperature Outdoor ambient temperature MUZ-WR24NA (PSIG) (PSIG) (°F) (°F) Outdoor ambient temperature Outdoor ambient temperature Heating Data is based on the condition of outdoor humidity 75%. Air flow should be set to High speed. Data is for heating operation without any frost.
  • Page 20 MUZ-WR09NA MUZ-WR12NA (PSIG) (PSIG) 58Hz 58Hz 75 (°F) 75 (°F) Outdoor ambient temperature Outdoor ambient temperature MUZ-WR18NA (PSIG) (PSIG) 58Hz 58Hz (°F) (°F) Outdoor ambient temperature Outdoor ambient temperature MUZ-WR24NA (PSIG) (PSIG) 81Hz 81Hz (°F) (°F) Outdoor ambient temperature Outdoor ambient temperature OBH819A...
  • Page 21 7-4. STANDARD OPERATION DATA Model MSZ-WR09NA MSZ-WR12NA Item Unit Cooling Heating Cooling Heating Capacity Btu/h 9,000 10,900 12,000 12,200 — 0.82 — 0.77 — Input 0.750 0.900 1.210 0.990 Rated frequency 59.5 79.0 89.0 90.0 Indoor unit MSZ-WR09NA MSZ-WR12NA Power supply V, phase, Hz 208/230, 1, 60 Input...
  • Page 22 7-4. STANDARD OPERATION DATA Model MSZ-WR18NA MSZ-WR24NA Item Unit Cooling Heating Cooling Heating Capacity Btu/h 17,200 18,000 22,500 26,000 — 0.86 — 0.89 — Input 1.64 1.59 2.63 Rated frequency Indoor unit MSZ-WR18NA MSZ-WR24NA Power supply phase, 208/230, 1, 60 Input 0.042 0.042...
  • Page 23 7-5. CAPACITY AND INPUT CORRECTION BY INVERTER OUTPUT FREQUENCY MUZ-WR09NA Correction of Cooling capacity Correction of Cooling total input Correction of Heating total input Correction of Heating capacity The operational frequency of compressor The operational frequency of compressor The operational frequency of compressor The operational frequency of compressor MUZ-WR12NA Correction of Cooling capacity...

  • Page 24: Actuator Control

    ACTUATOR CONTROL MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA MUZ-WR24NA 8-1. OUTDOOR FAN MOTOR CONTROL The fan motor turns ON/OFF, interlocking with the compressor. [ON] The fan motor turns ON 5 seconds before the compressor starts up. [OFF] The fan motor turns OFF 15 seconds after the compressor has stopped running. 5 seconds 15 seconds Compressor...

  • Page 25: Service Functions

    SERVICE FUNCTIONS MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA MUZ-WR24NA 9-1. CHANGE IN DEFROST SETTING Changing defrost finish temperature <JS> To change the defrost finish temperature, cut/solder the JS wire of the outdoor inverter P.C. board (Refer to 10-6.1.). Defrost fi nish temperature Jumper MUZ-WR09/12 MUZ-WR18 MUZ-WR24...

  • Page 26: Troubleshooting

    TROUBLESHOOTING MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA MUZ-WR24NA 10-1. CAUTIONS ON TROUBLESHOOTING 1. Before troubleshooting, check the following 1) Check the power supply voltage. 2) Check the indoor/outdoor connecting wire for miswiring. 2. Take care of the following during servicing 1) Before servicing the air conditioner, be sure to turn OFF the main unit first with the remote controller, then after con- firming the horizontal vane is closed, turn off the breaker and/or disconnect the power plug.
  • Page 27 10-2. FAILURE MODE RECALL FUNCTION Outline of the function This air conditioner can memorize the abnormal condition which has occurred once. Even though LED indication listed on the troubleshooting check table (10-3.) disappears, the memorized failure details can be recalled. 1.
  • Page 28 2. Flow chart of the detailed outdoor unit failure mode recall function Operational procedure The outdoor unit might be abnormal. Check if outdoor unit is abnormal according to the following procedures. Make sure that the remote controller is set to the failure mode recall function. 1.
  • Page 29 3. Table of outdoor unit failure mode recall function NOTE: Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (10-3.). MUZ-WR09NA MUZ-WR12NA OPERATION Indoor/ Outdoor unit INDICATOR Abnormal point LED indication outdoor unit Condition Remedy failure mode upper lamp (Failure mode / protection) (Outdoor P.C.
  • Page 30 NOTE: Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (10-3.). OPERATION Indoor/ Outdoor unit INDICATOR Abnormal point LED indication outdoor unit Condition Remedy failure mode upper lamp (Failure mode / protection) (Outdoor P.C. board) failure mode recall function (Indoor unit) recall function...
  • Page 31 NOTE: Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (10-3.). MUZ-WR18NA MUZ-WR24NA The upper lamp of the Indoor/outdoor Outdoor unit OPERATION Abnormal point LED indication unit failure Condition Remedy failure mode INDICATOR (Failure mode/protection) (Outdoor P.C. board) mode recall recall function lamp...
  • Page 32 NOTE: Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (10-3.). The upper lamp of the Indoor/outdoor Outdoor unit OPERATION Abnormal point LED indication unit failure Condition Remedy failure mode INDICATOR (Failure mode/protection) (Outdoor P.C. board) mode recall recall function lamp...
  • Page 33 10-3. TROUBLESHOOTING CHECK TABLE Abnormal point/ Symptom LED indication Condition Remedy Condition Outdoor unit 1-time blink every Outdoor power sys- Overcurrent protection cut-out operates 3 consecutive times • Reconnect connector of compres- does not op- 2.5 seconds within 1 minute after the compressor gets started. sor.
  • Page 34 Abnormal point/ Symptom LED indication Condition Remedy Condition Outdoor unit 1-time blink Frequency drop by MUZ-WR Current from power outlet is nearing Max. fuse The unit is normal, but check the operates. 2.5 seconds OFF current protection 09/12NA size. following. •...
  • Page 35 10-4. TROUBLE CRITERION OF MAIN PARTS MUZ-WR09NA MUZ-WR12NA MUZ-WR18NA MUZ-WR24NA Part name Check method and criterion Figure Defrost thermistor (RT61) Fin temperature thermistor (RT64) Measure the resistance with a tester. Ambient temperature thermis- Refer to 10-6. “Test point diagram and voltage”, 1. “Inverter P.C. tor (RT65) board”, for the chart of thermistor.
  • Page 36 10-5. TROUBLESHOOTING FLOW A How to check inverter/compressor Disconnect the connector between the compressor and the power module (IC700). Check the voltage between terminals. See 10-5. “Check of open phase”. Are the voltages balanced? Replace the inverter P.C. board. Check the compressor. See 10-5.
  • Page 37 D Check of compressor winding ●Disconnect the connector between the compressor and the power module (IC700), and measure the resistance between the compressor terminals. <<Measurement point>> At 3 points BLK-WHT Measure the resistance between the lead wires at 3 points. BLK-RED WHT-RED <<Judgement>>...
  • Page 38 G Check of outdoor thermistors Disconnect the connector of thermistor in the inverter P.C. board (see below table), and measure the resistance of thermistor. Replace the thermistor except RT64. Is the resistance of thermistor normal? When RT64 is abnormal, replace the inverter P.C. (Refer to 10-6.1.) board.
  • Page 39 I Check of outdoor fan motor Check the connection between the connector CN931 and CN932. Disconnect the connectors CN931 and CN932 from the inverter P.C. board. Is the resistance between each ter- minal of outdoor fan motor normal? (Refer to 10-4.) Disconnect CN932 from the inverter P.C.
  • Page 40 J Check of power supply Disconnect the connector between the compressor and the power module (IC700) Turn ON power supply and press Rectify indoor/outdoor EMERGENCY OPERATION switch. connecting wire. Does the upper lamp of the Is there voltage 208/230 V AC Replace the indoor OPERATION INDICATOR lamp on between the indoor terminal...
  • Page 41 K Check of LEV (Expansion valve) Turn ON the power supply. <Preparation of the remote controller> While pressing both OPERATION SELECT button and TOO COOL button on the remote controller at the same time, press RESET button. First, release RESET button. Hold down the other 2 buttons for another 3 seconds.
  • Page 42 L Check of inverter P.C. board Check the outdoor fan motor. (Refer to 10-5. .) Is the fuse (F901) blown on the in- verter P.C. board? Check the connection of the connectors (CN931, CN932) of the outdoor fan motor. If the connection is poor, make it correct. Operate the outdoor unit by starting EMERGENCY OPERATION.
  • Page 43 M How to check miswiring and serial signal error MUZ-WR09/12NA Turn OFF the power supply. Is there rated voltage in the power supply? Check the power supply. Turn ON the power supply. Is there rated voltage between outdoor terminal block S1 and S2? Check the wiring.
  • Page 44 MUZ-WR18/24NA Turn OFF the power supply. NOTE: Refer to the indoor unit service manual. Is there rated voltage in the power supply? Check the power supply. Turn ON the power supply. Is there rated voltage between outdoor terminal block S1 and S2? Check the wiring.
  • Page 45 N Check of defrost heater (Optional parts) Check the following points before checking electric continuity. 1. Does the resistance of ambient temperature thermistor have the characteristics? Refer to 10-6.1. 2. Is the resistance of defrost heater normal? Refer to 10-4. 3.
  • Page 46 P Electromagnetic noise enters into TV sets or radios Is the unit grounded? Ground the unit. Is the distance between the antennas Extend the distance between the antennas and and the indoor unit within 9.91 ft. (3m), the indoor unit, and/or the antennas and the or is the distance between the antennas outdoor unit.
  • Page 47 10-6. TEST POINT DIAGRAM AND VOLTAGE 1. Inverter P.C. board R.V.coil/21S4 Heater con- MUZ-WR09NA MUZ-WR12NA (CN721) nector (CN722) 208/230 V AC (Optional part) Smoothing Smoothing DB61 Back side of unit capacitor (C62) capacitor (C61) 260 - 370 V DC Fuse (F701) Fuse (F801) 208/230 V AC T3.15AL250V...
  • Page 48 1. Inverter P.C. board MUZ-WR18NA Smoothing capacitor (C63) R.V.coil/21S4 Smoothing Heater connector (CN721) Smoothing DB61 capacitor (C61) Back side of unit (CN722) 208/230 V AC capacitor (C62) 260 - 370 V DC (Optional parts) Fuse (F701) Fuse (F801) 208/230 V AC T3.15AL250V T3.15AL250V Fuse (F901)
  • Page 49 1. Inverter P.C. board MUZ-WR24NA Smoothing R.V.coil/21S4 capacitor (C63) (CN721) Smoothing Smoothing Back side of unit DB61 Heater connector 208/230 V AC capacitor (C62) capacitor (C61) 260 - 370 V DC (CN722) (Optional parts) Fuse (F701) Fuse (F801) 208/230 V AC T3.15AL250V T3.15AL250V Fuse (F901)

  • Page 50: Disassembly Instructions

    DISASSEMBLY INSTRUCTIONS <Detaching method of the terminal with locking mechanism> The terminal which has the locking mechanism can be detached as shown below. There are 2 types of terminals with locking mechanism. The terminal without locking mechanism can be detached by pulling it out. Check the shape of the terminal before detaching.
  • Page 51 OPERATING PROCEDURE PHOTOS/FIGURES Photo 4 Photo 5 Screws of the Screw of the conduit cover conduit plate 2. Removing the inverter assembly, inverter P.C. board Photo 6 (1) Remove the cabinet and panels. (Refer to section 1.) Screws of the heat sink (2) Disconnect the lead wire to the reactor and the following support and the separator connectors:...
  • Page 52 OPERATING PROCEDURE PHOTOS/FIGURES 4. Removing the discharge temperature thermistor, Photo 8 defrost thermistor, outdoor heat exchanger tempera- ture thermistor and ambient temperature thermistor (1) Remove the cabinet and panels. (Refer to section 1.) (2) Disconnect the lead wire to the reactor and the following connectors: <Inverter P.C.
  • Page 53 OPERATING PROCEDURE PHOTOS/FIGURES 5. Removing outdoor fan motor Photo 10 Screws of the outdoor fan motor (1) Remove the cabinet and panels. (Refer to section 1.) (2) Disconnect the following connectors: <Inverter P.C. board> CN931, CN932 (Fan motor) (3) Remove the propeller fan nut. (4) Remove the propeller fan.
  • Page 54 11-2. MUZ-WR24NA NOTE: Turn OFF the power supply before disassembly. OPERATING PROCEDURE PHOTOS/FIGURES 1. Removing the cabinet Photo 1 Screws of the top panel (1) Remove all the screws of the service panel. (2) Remove all the screws of the top panel. (3) Remove the screw of the valve cover.
  • Page 55 OPERATING PROCEDURE PHOTOS/FIGURES 2. Removing the inverter assembly, inverter P.C. board Photo 5 Screws of the terminal (1) Remove the cabinet and panels. (Refer to section 1.) Screw of the heat sink block support and the (2) Disconnect the lead wire to the reactor and the following con- support and the separator back panel nectors:...
  • Page 56 OPERATING PROCEDURE PHOTOS/FIGURES Outdoor heat 4. Removing the discharge temperature thermistor, Photo 8 exchanger tempera- Ambient tem- defrost thermistor, outdoor heat exchanger tempera- ture thermistor perature ture thermistor and ambient temperature thermistor thermistor (1) Remove the cabinet and panels. (Refer to section 1.) (2) Disconnect the lead wire to the reactor and the following connectors: <Inverter P.C.
  • Page 57 OBH819A...
  • Page 58 HEAD OFFICE: TOKYO BUILDING, 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN © Copyright 2018 MITSUBISHI ELECTRIC CORPORATION Issued: Jan. 2019. No. OBH819 REVISED EDITION-A Published: Sep. 2018. No. OBH819 Made in Japan Specifications are subject to change without notice.

This manual is also suitable for:

Muz-wr09naMuz-wr12naMuz-wr18naMuz-wr24na

Table of Contents