Revision A: • MUZ-FE18NA has been added. TECHNICAL CHANGES MUZ-FE09NA MUZ-FE12NA MUZ-FE18NA 1. New model PART NAMES AND FUNCTIONS MUZ-FE09NA MUZ-FE12NA Air inlet (back and side) Piping Drain hose Air outlet Drain outlet MUZ-FE18NA Air inlet (back and side) Piping...
OUTLINES AND DIMENSIONS MUZ-FE09NA MUZ-FE12NA Unit: inch REQUIRED SPACE Basically open 4 inch or more without any obstruction in front 15-3/4 Drain hole 1-5/8 and on both sides of the unit. Air in Air in 1-9/16 Air out 2- 3/8...
7-2. PERFORMANCE CURVE Cooling Cooling capacity (at Rated frequency) Indoor intake air Wet-bulb temperature( F) Outdoor intake air Dry-bulb temperature(°F) MUZ-FE09NA MUZ-FE12NA SHF at rating condition = 0.76 SHF at rating condition = 0.73 = 350 CFM Airflow = 307 CFM Airflow Outdoor intake air DB temperature (°F)
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Heating Heating capacity (at Rated frequency) Outdoor intake air Wet-bulb temperature (°F) MUZ-FE12NA MUZ-FE09NA Airflow = 420 CFM Airflow = 381 CFM Outdoor intake air WB temperature (°F) Outdoor intake air WB temperature (°F) MUZ-FE18NA = 738 CFM Airflow Outdoor intake air WB temperature (°F) This value of frequency is not the same as the actual frequency in operating.
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7-3. CONDENSING PRESSURE Cooling Data is based on the condition of indoor humidity 50 %. Air flow should be set to High speed. MUZ-FE09NA (PSIG) (PSIG) 68 70 105(°F) 68 70 105(°F) Outdoor ambient temperature Outdoor ambient temperature MUZ-FE12NA (PSIG)
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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. MUZ-FE09NA (PSIG) (PSIG) 58Hz 58Hz 15 20 25 30 35 40 45 50 55 60 65 70(°F) 20 25 30 35 40 45 50 55 60 65 70(°F)
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208/230, 1, 60 Input 0.018 0.024 0.024 0.030 0.058 Fan motor current 0.19/0.17 0.25/0.23 0.25/0.23 0.32/0.29 0.56/0.51 Outdoor unit MUZ-FE09NA MUZ-FE12NA MUZ-FE18NA Power supply phase, 208/230, 1, 60 Input 0.562 0.686 0.906 0.920 1.212 1.482 Comp. current 2.38/2.15 2.98/2.70 4.05/3.66...
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7-5. CAPACITY AND INPUT CORRECTION BY INVERTER OUTPUT FREQUENCY MUZ-FE09NA Correction of Cooling capacity Correction of Cooling total input Correction of Heating total input Correction of Heating capacity (Hz) (Hz) (Hz) (Hz) The operational frequency of compressor The operational frequency of compressor...
ACTUATOR CONTROL MUZ-FE09NA MUZ-FE12NA MUZ-FE18NA 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.
SERVICE FUNCTIONS MUZ-FE09NA MUZ-FE12NA MUZ-FE18NA 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-FE09/12NA...
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. MSZ-FE09NA MSZ-FE18NA 1.
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2. Flow chart of the detailed outdoor unit failure mode recall function Operational procedure The outdoor unit might be abnormal. Confi rm if outdoor unit is abnormal according to the following procedures. Confi rm that the remote controller is in the failure mode recall function. With the remote controller headed towards the indoor unit, press TOO 1.
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3. Outdoor unit failure mode table OPERATION Indoor/ INDICATOR Outdoor unit Abnormal point LED indication outdoor unit POWER lamp Condition Remedy failure mode (Failure mode/protection) (Outdoor P.C. board) failure mode Upper lamp recall function recall function (Indoor unit) None (Normal) —...
10-3. TROUBLESHOOTING CHECK TABLE Abnormal point/ Con- Symptom LED indication Condition Remedy dition Outdoor unit 1-time fl ash every Outdoor power sys- Overcurrent protection stop is continuously performed 3 times • Reconnect connector of compres- does not oper- 2.5 seconds within 1 minute after the compressor gets started, or failure of sor.
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Abnormal point/ Con- Symptom LED indication Condition Remedy dition Outdoor unit 7-time fl ash Low discharge tem- Temperature of discharge temperature thermistor has been • Refer to 10-5. "Check of LEV". operates. 2.5 seconds OFF perature protection 122°F (50°C) or less for 20 minutes. •...
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10-4. TROUBLE CRITERION OF MAIN PARTS MUZ-FE09NA MUZ-FE12NA MUZ-FE18NA Part name Check method and criterion Figure Defrost thermistor (RT61) Measure the resistance with a tester. Ambient temperature thermistor (RT65) Refer to 10-6. “Test point diagram and voltage”, 1. “Inverter P.C.
10-5. TROUBLESHOOTING FLOW A How to check inverter/compressor Disconnect the connector between compressor and the intelligent power module (IPM). See 10-5. “Check of open phase”. Check the voltage between terminals. Are the voltages balanced? Replace the inverter P.C. board. Check the compressor. See 10-5.
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D Check of compressor winding ● Disconnect the connector between the compressor and intelligent power module, 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>>...
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Turn ON the power supply and press EMERGENCY OPERATION switch. Does the unit operate for 10 minutes or more Replace the inverter P.C. board. without showing thermistor abnormality? OK. (Cause is poor contact.) MUZ-FE09NA MUZ-FE12NA Thermistor Symbol Connector, Pin No. Board...
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I Check of outdoor fan motor MUZ-FE09NA MUZ-FE12NA Disconnect CN932 from the inverter P.C. board, and measure the resistance of the outdoor fan motor. Is the outdoor fan motor normal? Replace the outdoor fan motor. (Refer to 10-4.) Replace the inverter P.C. board.
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J Check of power supply MUZ-FE09NA MUZ-FE12NA Disconnect the connector (CN61) between compressor and intelligent power module. Rectify indoor/outdoor Turn ON power supply and press connecting wire. EMERGENCY OPERATION switch. Replace the indoor Is there voltage 208/230 VAC Does POWER lamp on the indoor between the indoor terminal electronic control P.C.
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MUZ-FE18NA Disconnect the connector between compressor and intelligent power module. Rectify indoor/outdoor Turn ON power supply and press connecting wire. EMERGENCY OPERATION switch. Does the upper lamp of Is there voltage 208/230 VAC Replace the indoor OPERATION INDICATOR on the between the indoor terminal electronic control P.C.
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MSZ-FE09NA MSZ-FE18NA K Check of LEV (Expansion valve) MSZ-FE12NA 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.
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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.
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M How to check miswiring and serial signal error 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.
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N 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., or is the indoor unit, and/or the antennas and the the distance between the antennas and outdoor unit.
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10-6. TEST POINT DIAGRAM AND VOLTAGE 1. Inverter P.C. board MUZ-FE09NA MUZ-FE12NA Smoothing Bus-bar voltage Smoothing Smoothing capacitor DB61 capacitor capacitor Fuse (F701) Back side of unit 260-325 VDC (C63) (C62) (C61) T3.15AL250V Fuse (F801) 208/230 VAC T3.15AL250V R.V. coil...
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MUZ-FE18NA Fuse (F62) Fuse (F601) R.V. coil (CN602) T2.0AL250V T3.15AL250V 208/230 VAC Jumper wire for changing defrost setting (JS) Jumper wire for pre-heat control setting (JK) Signal of out- Defrost thermistor door fan motor /RT61 (CN671) (CN931) Discharge temperature thermistor/RT62 (CN671) Outdoor heat exchanger temperature thermistor...
Locking lever lever. Connector 11-1. MUZ-FE09NA MUZ-FE12NA NOTE: Turn OFF power supply before disassembling. OPERATING PROCEDURE PHOTOS 1. Removing the cabinet Photo 1 (1) Remove the screw fixing the service panel. (Photo 1) (2) Pull down the service panel and remove it.
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OPERATING PROCEDURE PHOTOS 2. Removing the inverter assembly, inverter P.C. board Photo 3 (1) Remove the cabinet and panels. (Refer to 1.) Screws of the (2) Disconnect the lead wire to the reactor and the following relay panel connectors: <Inverter P.C. board> CN721 (R.V.coil) CN932 (Fan motor) CN641 (Defrost thermistor and discharge temperature ther-...
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OPERATING PROCEDURE PHOTOS Photo 6 5. Removing outdoor fan motor Outdoor heat (1) Remove the cabinet and panels. (Refer to 1.) exchanger tempera- (2) Disconnect the connectors for outdoor fan motor. ture thermistor (3) Remove the propeller nut. (Photo 7) (4) Remove the propeller.
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11-2. MUZ-FE18NA NOTE: Turn OFF power supply before disassembling. OPERATING PROCEDURE PHOTOS 1. Removing the cabinet Photo 1 Screws of the top panel (1) Remove the screws of the service panel. (2) Remove the screws of the top panel. (3) Remove the screw of the valve cover. (4) Remove the service panel.
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OPERATING PROCEDURE PHOTOS 2. Removing the inverter assembly, inverter P.C. board Photo 4 Screw of the (1) Remove the cabinet and panels. (Refer to 1.) relay panel Screws of the (2) Disconnect the lead wire to the reactor and the following con- Inverter P.C PB support Earth wires...
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OPERATING PROCEDURE PHOTOS 4. Removing the discharge temperature thermistor, Photo 6 defrost thermistor, outdoor heat exchanger tempera- Outdoor heat Ambient tem- exchanger tempera- ture thermistor and ambient temperature thermistor perature ture thermistor thermistor (1) Remove the cabinet and panels. (Refer to 1.) (2) Disconnect the lead wire to the reactor and the following connectors: <Inverter P.C.