OB297--1.qxp 04.2.4 4:19 PM Page 1 Revision A: ● Conditions of operation frequency have been added. SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS Please void OB297. No. OB297 REVISED EDITION-A SERVICE MANUAL Wireless type Models MSZ09UN MSZ12UN · MUZ09UN · MUZ12UN (W) (W) CONTENTS MSZ09UN INDOOR UNIT 1. FEATURES ·························································2 2. PART NAMES AND FUNCTIONS······················4 3. SPECIFICATION·················································6 4.
OB297--1.qxp 04.2.4 4:19 PM Page 2 Revision A: • Conditions of operation frequency have been added. • SPECIFICATION, DATA, WIRING DIAGRAM and PARTS LIST have been partially modified. FEATURES 1 Optimum comfort year-round High–speed cooling & heating Ideal and comforting performance is assured by controlling compressor rotation according to the cooling and heat load of a room.
OB297--1.qxp 04.2.4 4:19 PM Page 3 The height of indoor unit has been shortened. (in.) Model Size MSH09EW MSZ09UN 14-13/16 10-15/16 MSH12EN MSZ12UN 14-3/16 12-5/8 “I FEEL CONTROL” IN OUR LCD WIRELESS REMOTE CONTROLLER WITH ON/OFF PROGRAM TIMER Mitsubishi Electric’s new wireless remote controller incorporates a number of advanced features that provides even greater control and ease-to-use.
OB297--1.qxp 04.2.
OB297--1.qxp 04.2.4 4:19 PM Page 5 ACCESSORIES 1 2 3 4 5 6 7 MSZ09UN MSZ12UN 1 5 1 2 2 1 1 1 6 1 2 2 1 1 Installation plate Installation plate fixing screw 4 x 25 mm(0.16 x 0.98 in.) Remote controller mounting hardware Fixing screw for 3 3.5 x 16 mm(0.14 x 0.63 in.
OB297--1.qxp 3 04.2.4 4:19 PM Page 6 SPECIFICATION Model Item ❈1 Capacity Cooling Btu/h Rated(Minimum~Maximum) Heating 47 ❈1 Btu/h Capacity Rated Heating 17 ❈2 Btu/h Power consumption Cooling ❈1 W Rated(Minimum~Maximum) Heating 47 ❈1 W Power consumption Rated Heating 17 ❈2 W EER ❈1 [SEER] ❈3 Cooling HSPF IV(V) ❈4 Heating COP Heating ❈1 INDOOR UNIT MODEL External finish Power supply V, phase, Hz Max. fuse size (time delay)/ Disconnect switch A Min. circuit ampacity A Fan motor F.L.
OB297--1.qxp 04.2.4 4:19 PM Page 7 Test condition (Unit : [˚F]) ❈3, ❈4 Mode ARI Indoor air condition Test Outdoor air condition Dry bulb Wet bulb Dry bulb Wet bulb SEER "A" Cooling Steady State (Cooling) at rated compressor Speed 80 67 95 (75) "B-2" Cooling Steady State at rated compressor Speed 80 67 82 (65) "B-1" Cooling Steady State at minimum compressor Speed 80 67 82 (65) Low ambient Cooling Steady State at minimum compressor Speed 80 67 67 (53.
OB297--1.qxp 04.2.4 4:19 PM Page 8 DATA 4 MSZ09UN MSZ12UN MUZ09UN MUZ12UN 4-1. PERFORMANCE DATA 1) COOLING CAPACITY Indoor air Model IWB (˚F) MSZ09UN MSZ12UN Outdoor intake air DB temperature(˚F) 75 85 95 105 TC SHC TPC TC SHC TPC TC SHC TPC TC SHC 71 10.8 6.1 0.87 10.1 5.7 0.96 9.5 5.4 1.03 8.8 5.0 67 10.2 7.1 0.82 9.5 6.7 0.91 8.8 6.2 0.98 8.2 63 9.6 8.0 0.78 8.9 7.4 0.87 8.3 6.9 0.94 71 14.0 8.3 1.01 13.1 7.8 1.11 12.3 7.3 67 13.2 9.
OB297--1.qxp 04.2.4 4:19 PM Page 9 4-2. PERFORMANCE CURVE How to operate with fixed operational frequency of the compressor. 1. Press the EMERGENCY OPERATION switch on the front of the indoor unit, and select either EMERGENCY COOL mode or EMERGENCY HEAT mode before starting to operate the air conditioner. 2. The compressor starts up. The operational frequency of the compressor is 64Hz in EMERGENCY COOL mode and 58Hz in EMERGENCY HEAT mode. 3. The fan speed of the indoor unit is High. 4.
OB297--1.qxp 04.2.4 4:19 PM Page 10 How to operate with fixed operational frequency of the compressor. 1. Press the EMERGENCY OPERATION switch on the front of the indoor unit, and select either EMERGENCY COOL mode or EMERGENCY HEAT mode before starting to operate the air conditioner. 2. The compressor starts up. The operational frequency of the compressor is 70Hz in EMERGENCY COOL mode and 58Hz in EMERGENCY HEAT mode. 3. The fan speed of the indoor unit is High. 4. This operation continues for 30minutes.
OB297--1.qxp 04.2.4 4:19 PM Page 11 4-3. Condensing pressure How to operate with fixed operational frequency of the compressor. 1. Press the EMERGENCY OPERATION switch on the front of the indoor unit, and select either EMERGENCY COOL mode or EMERGENCY HEAT mode before starting to operate the air conditioner. 2. The compressor starts up. The operational frequency of the compressor is MSZ09UN: 64Hz, MSZ12UN: 70Hz in EMERGENCY COOL mode and 58Hz in EMERGENCY HEAT mode. 3.
OB297--1.qxp 04.2.4 4:19 PM Page 12 MSZ12UN (Cooling) Data is based on the condition of indoor humidity 50%. Air flow should be set to High speed.
OB297--1.qxp 04.2.4 4:20 PM Page 13 4-4. STANDARD OPERATION DATA Model Item Cooling Heating Cooling Heating Btu / h 8,800 12,300 11,400 16,000 SHF — 0.70 – 0.73 – Input kW 980 1,320 1,140 1,590 Rated frequency Hz 64 76 70 Unit Capacity Total 99 Indoor unit MSZ09UN MSZ12UN Power supply (V, phase, Hz) 115, 1, 60 115, 1, 60 kW 0.035 0.047 Fan motor current A 0.34 0.41 Aux.
OB297--1.qxp 04.2.4 4:20 PM Page 14 4-5. OPERATING RANGE (1) POWER SUPPLY Rated voltage Model Guaranteed Voltage Min. 103V Indoor unit MSZ09UN MSZ12UN 115V 1phase 60Hz Outdoor unit MUZ09UN MUZ12UN 208/230V 1phase 60Hz 115V Max. 127V Min. 198V 208V 230V Max.
OB297--1.qxp 04.2.4 4:20 PM MSZ09UN MUZ09UN Page 15 MSZ12UN MUZ12UN The standard data contained in these specifications apply only to the operation of the system under normal conditions. Since operating conditions vary according to the areas where these units are installed. The following information has been provided to clarify the operating characteristics of the system under the conditions indicated by the performance curve.
OB297--1.qxp 04.2.4 4:20 PM Page 16 Cooling capacity ✴ These values are under rated (frequency). 18.7 13.9 17.1 12.8 15.5 11.7 14.0 10.6 12.6 9.5 11.2 8.5 79 79 75 75 72 68 64 72 68 MSZ12UN MSZ09UN 64 80 85 90 95 100 105 110 80 85 Correction of Cooling capacity 100 105 110 Correction of total input 1.5 1.5 Input correction factors Capacity correction factors 95 MUZ09UN MUZ09UN 1.0 0.5 0.0 0 50 100 1.0 0.5 0.
OB297--1.qxp 04.2.4 4:20 PM Page 17 Heating capacity NOTE:The following curves are for the heating operation without any frost. ✴ These values are under rated (frequency). 43.2 1.4 46.6 39.8 1.3 42.7 36.5 1.2 38.9 33.1 1.1 34.9 30.0 1.0 31.0 26.5 0.9 27.2 23.2 0.8 23.2 20.0 0.7 MSZ12UN 0.6 14 59 68 79 79 68 59 30 20 40 60 50 14 Correction of Heating capacity 30 40 50 60 Correction of total input 1.5 Input correction factors 1.
OB297--1.qxp 04.2.4 4:20 PM 5 Page 18 OUTLINES AND DIMENSIONS Unit: inch 3-1/4 3/16 INDOOR UNIT 6-5/8 9-1/8 Installation plate Indoor unit 10-11/16 MSZ09UN 3-1/4 12-13/16 33-1/2 3/4 2-5/8 Air out 3-1/16 Liquid line [1/4 19-11/16 Gas line [3/8 16-15/16 Insulation [1-7/16 O.D [13/16 I.D Drain hose [5/8 (Connected part O.
04.2.4 4:20 PM Page 19 MUZ09UN MUZ12UN OUTDOOR UNIT Even if the right/left sides or back side are vacant, the top has to be at least 4 in. unobstructed. 4 in . or Drainage holes [1-3/32 1-9/32 1-9/16 Air out . or 4 in e mor re ly ical ted Bas bstruc uno 14 in. o rm Even if the right/left sides or back side ore are vacant, the front has to be at least 4 in. unobstructed. WA In case of poorly-ventilated place, the front or the back has to be at least 8 in. unobstructed.
OB297--1.qxp 04.2.4 4:20 PM 6 Page 20 WIRING DIAGRAM MSZ09UN INDOOR UNIT ( TO OUTDOOR UNIT CONNECTING WIRES 12V DC FROM OUTDOOR UNIT CONNECTING WIRES POWER SUPPLY 115V 1 phase 60Hz TO OUTDOOR UNIT CONNECTING WIRE MODEL WIRING DIAGRAM TB ORN 3+ ) N BLK L1 RED 5 POWER MONITOR, RECEIVER P.C.
OB297--1.qxp 04.2.4 4:20 PM Page 21 MUZ09UN MUZ12UN MODELS WIRING DIAGRAM OUTDOOR UNIT LDE2 BLK L1 RED CN721 1 2 CN771 6 5 4 3 2 1 TB1 N RED BLK L2 BLU FROM INDOOR UNIT RED L1 RELAY P.C.
OB297--1.qxp 7 04.2.4 4:20 PM Page 22 REFRIGERANT SYSTEM DIAGRAM Unit:inch MUZ09UN MSZ09UN OUTDOOR UNIT INDOOR UNIT Refrigerant pipe {3/8 (with heat insulator) Indoor heat exchanger Main indoor coil thermistor RT12 Flared connection 4-way valve Muffler Stop valve (with service port) Fusible plug Service port Discharge temperature thermistor RT62 Service port Sub indoor coil thermistor Room RT13 Temperature thermistor RT11 Muffler Compressor Defrost thermistor RT61 Capillary tube O.D.0.12OI.
OB297--1.qxp 04.2.4 4:20 PM 8 Page 23 MICROPROCESSOR CONTROL MSZ09UN MSZ12UN MUZ09UN MUZ12UN Once the operation mode are set, the same operation mode can be repeated by simply turning the OPERATE/STOP(ON/OFF) button ON. Indoor unit receives the signal with a beep tone. When the system turns off, 3-minute time delay will operate to protect system from overload and compressor will not restart for 3 minutes.
OB297--1.qxp 04.2.4 4:20 PM Page 24 8-1. “I FEEL CONTROL” OPERATION (1) Press OPERATE/STOP(ON/OFF) button on the remote controller. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Press OPERATION SELECT button to set “I FEEL CONTROL”. Then a beep tone is heard. (3) The operation mode is determined by the room temperature at start-up of the operation.
OB297--1.qxp 04.2.4 4:20 PM Page 25 (5) TEMPERATURE buttons In “I FEEL CONTROL” mode, set temperature is decided by the microprocessor based on the room temperature. In addition, set temperature can be controlled by TOO WARM or TOO COOL buttons when you feel too cool or too warm. Each time the TOO WARM or TOO COOL button is pressed, the indoor unit receives the signal and emits a beep tone.
OB297--1.qxp 04.2.4 4:20 PM Page 26 ON ON Compressor and Outdoor fan motor OFF OFF ON Indoor fan motor (continuously at set speed) 8-1-2. DRY mode of “I FEEL CONTROL” The system for dry operation uses the same refrigerant circuit as the cooling circuit. The compressor and the indoor fan are controlled by the temperature. By such controls, amount of air flow of indoor unit will be reduced in order to lower humidity without much room temperature drop. MSZ09UN 1.
OB297--1.qxp 04.2.4 4:20 PM Page 27 Operation time chart Example Thermostat ON ON OFF OFF Indoor fan OFF OFF ON Outdoor fan Compressor 8 min. OFF ON OFF OFF ON ON ON ON OFF 3 min. 4 min. 1 min. 3. Coil frost prevention • The operation is as same as coil frost prevention during COOL mode of “I FEEL CONTROL”. • Indoor fan operates at the set speed and the compressor stops for 5 minutes, because protection (Coil frost prevention) has the priority.
OB297--1.qxp 04.2.4 4:20 PM Page 28 (3) Warm air control. When any condition of 1(a. ~ d.) and the condition of 2 as follows are satisfied at the same time, warm air control works. 1 a.) when the operation mode has been changed to HEAT mode b.) when cold air prevention has been released c.) when defrosting has been finished d.) when the compressor starts in HEAT mode 2 When the temperature of indoor coil thermistor RT12 is less than 99°F.
OB297--1.qxp 04.2.4 4:20 PM Page 29 Time chart of defrosting in HEAT mode (reverse type) Horizontal vane horizontal set position set position Indoor fan set speed Very Low (temperature of indoor coil thermistor > 64°F) OFF 30 seconds MAX. Hz MAX. 79Hz (MSZ12UN) MAX. 80Hz (MSZ09UN) MAX. Hz Compressor normal OFF 30 seconds 1second OFF 30 seconds 5 seconds 1second 5 seconds ON ON Outdoor fan OFF R.V. coil (21S4) ON ON OFF 5. R.V.
OB297--1.qxp 04.2.4 4:20 PM Page 30 6. 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. ON 5 sec. 15 sec. Compressor OFF ON Outdoor fan OFF 8-2. COOL OPERATION (1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
OB297--2.qxp 04.2.4 4:21 PM Page 31 8-5. FAN MOTOR CONTROL (1) Rotational frequency feedback control The indoor fan motor is equipped with a rotational frequency sensor, and outputs signal to the microprocessor to feedback the rotational frequency. Comparing the current rotational frequency with the target rotational frequency (High, Med.
OB297--2.qxp 04.2.4 4:21 PM Page 32 (7) SWING MODE By selecting SWING mode with the VANE CONTROL button, the horizontal vane swings vertically. The remote controller displays “ ”. (8) Cold air prevention in HEAT operation. When any of the following conditions occurs in HEAT operation, the horizontal vane angle changes to Angle 1 automatically to prevent cold air blowing on users. ① Compressor is not operating. ➁ Defrosting is performed. ➂ Indoor coil thermistor RT12 reads 75˚F or below.
OB297--2.qxp 04.2.4 4:21 PM Page 33 8-8. EMERGENCY-TEST OPERATION In case of test run operation or emergency operation, use the EMERGENCY OPERATION switch on the front of the indoor unit. Emergency operation is available when the remote controller is missing, has failed or the batteries of remote controller run down. The unit will start and the OPERATION INDICATOR lamp will light. The first 30 minutes of operation is the test run operation. This operation is for servicing.
OB297--2.qxp 04.2.4 4:21 PM Page 34 (2) At normal operation Alternating current supplied from power supply is eliminated of any noise by L62(Common mode choke coil) and L63 (Common mode choke coil). Then DS61(Diode stack) performs full-wave rectification of alternating current and the alternating current is converted to direct current. C63(Smoothing capacitor) stabilizes the power supply converted to direct current from alternating current and supplies it to IPM(Intelligent power module).
OB297--2.qxp 04.2.4 4:21 PM Page 35 8-10. Operational frequency control of outdoor unit 1. Outline The operational frequency is as following: First, the target operational frequency is set based on the difference between the room temperature and the set temperature. Second, the target operational frequency is regulated by discharge temperature protection, high pressure protection, electric current protection and overload protection and also by the maximum/minimum frequency.
OB297--2.qxp 04.2.4 4:21 PM Page 36 3. Frequency control by estimated discharge temperature (for protecting the discharge temperature in case the estimated discharge temperature is 212 °F or higher) By calculating the difference between the current discharge temperature and the discharge temperature 15 seconds before, a discharge temperature in one minutes is estimated. As a result, the frequency and LEV are controlled as shown the table below.
OB297--2.qxp 04.2.4 4:21 PM Page 37 8-12. Expansion valve control (LEV control) general operation standard specification (1) Outline of LEV control The LEV basic control is comprised of setting LEV opening degree to the standard opening degrees set for each operational frequency of the compressor.
OB297--2.qxp 04.2.4 4:21 PM Page 38 (2) Time chart Air conditioner ON Air conditioner OFF (thermostat off) LEV opening degree Positioning Opening degree is corrected according to discharge temperature.
OB297--2.qxp 04.2.4 4:21 PM 9 Page 39 SERVICE FUNCTIONS MSZ09UN MSZ12UN MUZ09UN MUZ12UN 9-1. CHANGE IN DEFROST SETTING When the JS wire of the outdoor electronic control P.C. board is cut, the defrost temperature will be changed. (Refer to page 58.) Jumper wire Change point JS Deforst finish temperature changes from 55°F to 59°F. 9-2. TIMER SHORT MODE For service, set time can be shortened by short circuit of JPG and JPS the indoor electronic control P.C. board.
OB297--2.qxp 04.2.4 4:21 PM Page 40 9-4. AUTO RESTART FUNCTION When the indoor unit is operated with the remote controller, the signals of the operation mode, the set temperature, and the fan speed are sent from the indoor electronic control P.C. board and memorized in the auto restart assembly. When the main power is turned off and then turned back on, the unit restarts automatically in the memorized set conditions approximately after 3 minutes.
OB297--2.qxp 04.2.4 4:21 PM 10 Page 41 TROUBLESHOOTING MSZ09UN MSZ12UN MUZ09UN MUZ12UN 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 mis-wiring. 2. Take care the following during servicing.
OB297--2.qxp 04.2.4 4:21 PM Page 42 10-2. Troubleshooting procedure The following procedure facilitates identifying defective points. Details of OPERATION INDICATOR lamp flashing are located on page 43. Start Indoor unit operates. Outdoor unit doesn't operate. Indoor unit does'nt receive the signal from remote controller. Outdoor unit operates in only Test Run operation. Outdoor unit does'nt operate even in Test Run operation. Indoor unit operates, when the EMERGENCY OPERATION switch is pressed.
OB297--2.qxp 04.2.4 4:21 PM Page 43 1. Troubleshooting check table • The following indication applies regardless of shape of the indicatior. flashing · Flashing of the OPERATION INDICATOR lamp (on the left-hand side) indicates possible abnormalities. · The OPERATION INDICATOR lamp (on the left-hand side) is lighted during normal operation. · Flashing of the operation indicator lamp (on the left-hand side) indicates possible abnormalities.
OB297--2.qxp 04.2.4 4:21 PM Page 44 (Outdoor LED indication table) MUZ09UN MUZ12UN NOTE 1. The location of LED is illustrated at the right figure. 2. LED lights up during normal operation. LED Transistor module Hybrid IC flashing transformer No. 1 Symptom LED indication Outdoor unit does not operate 1-time flash every 2.5 seconds NOTE: For abnormality location, refer to 'Indoor troubleshooting check table' on page 43.
OB297--2.qxp 04.2.4 4:21 PM Page 45 2. Trouble criterion of main parts Check method and criterion Part name Figure Room temperature thermistor(RT11) Measure the resistance with a tester. (Part temperature 50°F ~ 86°F) Main indoor coil thermistor(RT12) Normal 8kΩ ~ 20kΩ Sub indoor coil thermistor(RT13) Abnormal Open or short-circuit Measure the resistance with a tester.
OB297--2.qxp 04.2.4 4:21 PM Page 46 Check method and criterion Part name Outdoor fan motor(MF61) INNER PROTECTOR 266I 14°F OPEN 174I 30°F CLOSE Figure Measure the resistance between the terminals with a tester. (Part temperature14°F ~ 104°F) BLK Color of lead wire WHT-BLK BLK-RED Normal 169~208Ω 246~301Ω Abnormal Open or short-circuit Measure the resistance between the terminals with a tester. (Part temperature 50°F ~ 86°F) P AUX.
OB297--2.qxp 04.2.4 4:21 PM Page 47 When OPERATION INDICATOR lamp flashes 5-time. Outdoor unit does not operate. A How to check inverter/ compressor Disconnect the connector between compressor and IPM. Check the voltage between terminals. Are voltages balanced? Refer to B “Check of open phase” on page 47. No Replace the outdoor electronic control P.C. board. Yes Check the compressor. Refer to D “Check of compressor” on page 48.
OB297--2.qxp 04.2.4 4:21 PM Page 48 D Check of compressor Start E 'Check of compressor winding' on page 48. Is compressor normal? No Replace the compressor. Yes F 'Check of compressor operation time' on page 48. Does the compressor operate continuously? Yes No Ok Is the compressor operation time more than 10 seconds? No Replace the compressor. Yes Check the refrigerant circuit.
OB297--2.qxp 04.2.4 4:21 PM Page 49 When OPERATION INDICATOR lamp flashes 3-time. Indoor fan does not operate. G Check of indoor fan motor Turn OFF the power supply. Check connector (Fan motor) visually. No Are lead wires connected? Yes Is soldered point of the connector correctly soldered? Yes Re-connect the lead wires. Disconnect lead wires from connector (Fan motor). Measure resistance between lead wires No.1 and No.3 and then No.2 and No.3 (MSZ09UN). No.1 and No.4 and then No.3 and No.
OB297--2.qxp 04.2.4 4:21 PM Page 50 Indoor unit operates by pressing the EMERGENCY OPERATION switch, but does not operate with the remote controller. H Check of remote controller and receiver P.C. board wCheck if the remote controller is exclusive for this air conditioner. wIn case of replacing the receiver P.C. board of MSZ09UN, replace the indoor electronic control P.C. board with it because they are unified. Switch on the remote controller.
OB297--2.qxp 04.2.4 4:21 PM Page 51 The unit doesn’t operate with the remote controller. Also, the OPERATION INDICATOR lamp doesn’t light up by pressing the EMERGENCY OPERATION switch. I Check of indoor electronic control P.C. board Check the both “parts side” and “pattern side” of indoor electronic control P.C. board visually. Turn OFF the power supply. Disconnect indoor fan motor connector CN211(MSZ09UN) and vane motor connector CN151 from the indoor electronic control P.C.
OB297--2.qxp 04.2.4 4:21 PM Page 52 Cooling operates when heating is expected. K Check of R.V. coil Measure resistance of the R.V. coil to check if it is defective or not. If the connector CN 721 is not connected or the R.V. coil is open, the voltage occurs between the terminals even when the control is OFF. R.V. coil 208/230V AC 1 2 CN721 Relay P.C. board Disconnect the connector between the compressor and transistor module.
OB297--2.qxp 04.2.4 4:21 PM Page 53 Inverter does not work. M Check of power supply Star Check the connecting of main circuit part, and connector. Turn on power supply. Is there 208-230V AC between terminal block L1 and L2 on the outdoor unit? No Check the power supply cable. Yes Is there 290-330V DC to smoothing capacitor (C61)? No No Is there 208-230V AC between terminal TAB69 and X64 (terminal 4)? Yes Check the current-limiting resistor (R64). Yes Replace the outdoor electronic control P.
OB297--2.qxp 04.2.4 4:21 PM Page 54 Heating/Cooling does not operate. O Check of expansion valve (LEV) 1Turn OFF the outdoor unit power supply. 2Turn ON the outdoor unit power supply. With remote controller set toward the indoor unit, press OPERATE/ STOP(ON/ OFF) button and confirm one beep tone. LEV operates in full-opening direction.
OB297--2.qxp 04.2.4 4:21 PM Page 55 When OPERATION INDICATOR lamp flashes once. Outdoor unit doesn’t operate. P How to check mis-wiring and serial signal error Start Turn OFF the power supply. Turn ON the power supply. No Rectify the wiring. Is the power voltage to terminal blocks of indoor/outdoor units normal? Yes Turn ON the EMERGENCY OPERATION switch.
OB297--2.qxp 04.2.4 4:21 PM Page 56 TEST POINT DIAGRAM AND VOLTAGE MSZ09UN Indoor electronic control P.C. board Varistor(NR11) Fuse(F11) 250V AC 3.0A Fan motor Power supply input 115V AC -+ } 12V DC Room temperature thermistor(RT11) Timer short mode point (JPS, JPG) (Refer to page 39.
OB297--2.qxp 04.2.4 4:21 PM Page 57 TEST POINT DIAGRAM AND VOLTAGE MSZ12UN Indoor electronic control P.C. board Fan motor 8 7 5 6 4 C11 } Very Med. Low High Low 3 2 1 Varistor(NR11) Fuse(F11) 250V AC 3.0A CN201 } Power supply input 115V AC JP17 + JP16 -- JP11 + JP24 -- CN104 JHA } } } 12V DC 5V DC Auto restart function Disconnect the AUTO RESTART ASSY from CN104, and solder the Jumper wire to JHA.(Refer to page 40.
OB297--2.qxp 04.2.4 4:21 PM Page 58 MUZ09UN MUZ12UN Outdoor electronic control P.C.
OB297--2.qxp 04.2.4 4:21 PM Page 59 MUZ09UN MUZ12UN Noise filter P.C. board Current -limiting relay (X64) Surge absorber (DSA61) } Varistor (NR61) MUZ09UN MUZ12UN Relay P.C. board 208/230V AC F901 R.V.
OB297--2.qxp 04.2.4 4:21 PM Page 60 RELAY OPERATION MSZ09UN MSZ12UN MODE THERMOSTAT X64 COOL & COOL mode of I FEEL CONTROL ON ON INDOOR FAN SPEED OUTDOOR FAN SPEED ON AUTO or set speed DRY & DRY mode of I FEEL CONTROL OFF ON ON OFF ON ON ON ON OFF MSZ09UN AUTO(=Low) or set speed Very Low speed MSZ12UN When the compressor operates. AUTO(=Low) or set speed When the compressor stops.
OB297--3.qxp 04.2.4 4:22 PM 11 Page 61 DISASSEMBLY INSTRUCTIONS <"Terminal with lock mechanism" Detaching points> In case of terminal with lock mechanism, detach the terminal as shown below. There are two types ( Refer to (1) and (2)) of the terminal with lock mechanism. The terminal with no lock mechanism can be removed by pulling it out. Check the shape of the terminal and work. (1) Slide the sleeve and check if there is a locking lever or not.
OB297--3.qxp 04.2.4 4:22 PM Page 62 OPERATING PROCEDURE PHOTOS Photo 3 3. Removing the electrical box (1) Remove the front panel. (Refer to 1.) (2) Remove the electrical cover. (Refer to 2.) (3) Disconnect the connector of the indoor coil thermistor(CN112). (4) Disconnect the motor connector (CN211 and CN121) and the vane motor connector (CN151) on the electronic control P.C. board. (5) Remove the screw of ground wire.
OB297--3.qxp 04.2.4 4:22 PM Page 63 OPERATING PROCEDURE PHOTOS 5. Removing the line flow fan and the indoor fan motor (1) Remove the front panel. (Refer to 1.) (2) Remove the electrical box. (Refer to 3.) (3) Pull out the drain hose from the nozzle assembly, remove the nozzle assembly. (4) Remove the hexagon socket set screw from the line flow fan. (5) Remove the screws fixing the fan motor, remove the fan motor. (6) Remove the screws fixing the left side of the heat exchanger.
OB297--3.qxp 04.2.4 4:22 PM Page 64 11-2. MSZ12UN INDOOR UNIT OPERATING PROCEDURE PHOTOS 1. Removing the front panel Photo 1 (1) Remove the screw caps at the bottom of the front panel. Remove the screws. (2) Pull the panel down to your side slightly and unhook the catches at the top. Front panel Screws Photo 2 2. Removing the electronic control P.C. board, the receiver P.C. board and the display P.C. board (1) (2) (3) (4) (5) (6) (7) (8) Remove the front panel. (Refer to 1.
OB297--3.qxp 04.2.4 4:22 PM Page 65 OPERATING PROCEDURE PHOTOS 3. Removing the electrical box (1) (2) (3) (4) Remove the front panel. (Refer to 1.) Remove the electrical cover. Remove the connector of the indoor coil thermistor (CN112). Remove the motor connector and the vane motor connector (CN151) on the electronic control P.C. board. (5) Remove the screw of the electrical box, remove the electrical box. Photo 3 Screws of the vane motor 4. Removing the vane motor (1) Remove the front panel.
OB297--3.qxp 04.2.4 4:22 PM Page 66 11-3. MUZ09UN MUZ12UN OUTDOOR UNIT OPERATING PROCEDURE PHOTOS 1. Removing the cabinet (1) Remove the screw fixing the service panel. (2) Pull down the service panel and remove it from the cabinet. (3) Remove the screws fixing the top panel and remove the top panel. (4) Remove the screws fixing the cabinet and remove the cabinet. Photo 1 Screws of the top panel Screw of the service panel Photo 2 Screws of the cabinet Hooks 2.
OB297--3.qxp 04.2.4 4:22 PM Page 67 OPERATING PROCEDURE PHOTOS 6. Removing the propeller and the outdoor fan motor Photo 5 (1) Remove the cabinet. (Refer to 1.) (2) Remove the propeller nut. (3) Remove the propeller. NOTE : Loose the propeller in the rotating direction for removal. When attaching the propeller, align the mark on the propeller and the motor shaft cut section. Set the propeller in position by using the cut on the shaft and the mark on the propeller.
OB297--3.qxp 12 04.2.4 4:22 PM Page 68 PARTS LIST MSZ09UN (W) 12-1. INDOOR UNIT STRUCTURAL PARTS 12-2. ACCESSORY AND REMOTE CONTROLLER 10 1 11 2 3 4 9 5 Optional parts (See page 74.) 6 7 8 12-1. INDOOR UNIT STRUCTURAL PARTS NO. Part No.
OB297--3.qxp 04.2.4 4:22 PM Page 69 MSZ09UN (W) 12-3. INDOOR UNIT ELECTRICAL PARTS AND FUNCTIONAL PARTS 1 18 12-4. INDOOR UNIT HEAT EXCHANGER 20 17 2 3 16 SLEEVE BEARING 4 ROOM TEMPERATURE THERMISTOR 19 5 13 6 11 12 7 FUSE 8 VARISTOR 9 10 15 14 21 22 12-3. INDOOR UNIT ELECTRICAL PARTS AND FUNCTIONAL PARTS NO. Part No.
OB297--3.qxp 04.2.4 4:22 PM Page 70 MSZ12UN (W) 12-5. INDOOR UNIT STRUCTURAL PARTS 12-6. ACCESSORY AND REMOTE CONTROLLER 8 1 9 2 3 Optional parts (See page 74.) 4 5 6 12-5. INDOOR UNIT STRUCTURAL PARTS Part number that is circled is not shown in the illustration. NO. Part No.
OB297--3.qxp 04.2.4 4:22 PM Page 71 MSZ12UN (W) 12-7. INDOOR UNIT ELECTRICAL PARTS AND FUNCTIONAL PARTS 2 1 12-8. INDOOR UNIT HEAT EXCHANGER 14 15 23 SLEEVE BEARING 3 18 4 5 13 10 17 6 16 12 INDOOR COIL THERMISTOR 7 8 9 11 ROOM TEMPERATURE THERMISTOR 25 24 12-7. INDOOR UNIT ELECTRICAL PARTS AND FUNCTIONAL PARTS Part numbers that are circled are not shown in the illustration. NO. Part No.
OB297--3.qxp 04.2.4 4:23 PM Page 72 MUZ09UN MUZ12UN 12-9. OUTDOOR UNIT STRUCTURAL PARTS AND FUNCTIONAL PARTS 15 17 16 14 12 13 11 10 1 2 9 8 3 4 5 7 6 Part numbers that are circled are not shown in the illustration. Symbol NO. Part No.
OB297--3.qxp 04.2.4 4:23 PM Page 73 MUZ09UN MUZ12UN 12-10. OUTDOOR UNIT ELECTRICAL PARTS 12 11 10 9 1 8 7 6 2 5 3 4 Part numbers that are circled are not shown in the illustration. NO. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Part No.
OB297--3.qxp 13 04.2.4 4:23 PM Page 74 OPTIONAL PARTS 13-1. REFRIGERANT PIPES , The air conditioner has flared connections its on indoor and outdoor sides. Please use the optional extension pipe as follows. Model MSZ09UN MUZ09UN MSZ12UN MUZ12UN Part No. Pipe length MAC-645PI MAC-646PI MAC-647PI MAC-648PI MAC-649PI MAC-660PI-US MAC-661PI-US MAC-662PI-US MAC-663PI-US MAC-664PI-US 10ft. 16ft. 23ft. 33ft. 49ft. 10ft. 16ft. 23ft. 33ft. 49ft. 13-2.
OB297--3.qxp 04.2.
OB297--3.qxp 04.2.4 4:23 PM Page 76 TM C Copyright 2002 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD Distributed in Feb. 2004. No.OB297 REVISED EDITION-A 7 Distributed in May 2002. No.OB297 23 New publication, effective Feb. 2004 Specifications subject to change without notice.
3400 Lawrenceville Suwanee Road ● Suwanee, Georgia 30024 Toll Free: 800-433-4822 ● Toll Free Fax: 800-889-9904 www.mrslim.com Specifications are subject to change without notice.
