Page 1: Table Of Contents
5. OUTLINES AND DIMENSIONS ...... 23 indication 6. WIRING DIAGRAM ......... 25 7. NECESSARY CONDITIONS FOR SYSTEM CONSTRUCTION ..28 8. TROUBLESHOOTING ........32 9. PRECAUTIONS AGAINST REFRIGERANT LEAKAGE ..132 10. DISASSEMBLY PROCEDURE ...... 133 OUTDOOR UNIT: MXZ-4C36NAHZ PARTS CATALOG (OCB573) BRANCH BOX: PAC-MKA50BC...
Page 2: Safety Precaution
SAFETY PRECAUTION 1-1. ALWAYS OBSERVE FOR SAFETY Before obtaining access to terminal, all supply circuit must be disconnected. 1-2. CAUTIONS RELATED TO NEW REFRIGERANT Cautions for units utilizing refrigerant R410A Use a vacuum pump with a reverse flow check Use new refrigerant pipes. valve.
Page 3 [1] Cautions for service (1) Perform service after recovering the refrigerant left in unit completely. (2) Do not release refrigerant in the air. (3) After completing service, charge the cycle with specified amount of refrigerant. (4) When performing service, install a filter drier simultaneously. Be sure to use a filter drier for new refrigerant.
Page 4 1-3. Cautions for refrigerant piping work New refrigerant R410A is adopted for replacement inverter series. Although the refrigerant piping work for R410A is same as for R22, exclusive tools are necessary so as not to mix with different kind of refrigerant. Furthermore as the working pressure of R410A is 1.6 times higher than that of R22, their sizes of flared sections and flare nuts are different.
Page 5: Overview Of Units
OVERVIEW OF UNITS 2-1. CONSTRUCTION OF SYSTEM Outdoor unit MXZ-8C48NAHZ MXZ-5C42NAHZ MXZ-4C36NAHZ MXZ-8C48NA 4.5HP Cooling Rated capacity (kBTU/h) Heating R410A Refrigerant Type 06 to Type 36 Capacity Connectable Caution: The indoor unit which rated capacity exceeds indoor unit 36 kBTU/ h (Type 36) can NOT be connected.
Page 6 2-2. SYSTEM OUTLINE The additional connection of the branch box together with employment of the compact trunk-looking outdoor unit can suc- cessfully realize a long distance piping for large houses. Equipped with a microcomputer, the branch box can translate the transmission signal of indoor units to achieve the optimum control.
Page 7 2-3. TYPICAL COMBINATION EXAMPLE Branch box is located INSIDE of condominium Branch box (Inside) Installing branch box indoors Only 1 piping is required between the outdoor and indoor offering a fine external view. ■ System example of 5 indoor units Branch box (5 branch type) Master Dining...
Page 8 2-4. SIMPLIFIED PIPING SYSTEM Piping connection size The piping connection size differs according to the type and capacity of indoor units. {3/8 in Liquid Match the piping connection size of branch box with indoor unit. [9.52 mm] If the piping connection size of branch box does not match the piping connection size of {5/8 in indoor unit, use optional different-diameter (deformed) joints to the branch box side.
Page 9: Specifications
SPECIFICATIONS kcal/h = kW o 860 Conversion formula: BTU/h = kW o 3412 3-1. OUTDOOR UNIT: MXZ-4C36/5C42/8C48NAHZ, MXZ-8C48NA /min o 35.31 Service Ref. MXZ-4C36NAHZ MXZ-5C42NAHZ Indoor type Non-Ducted Ducted Non-Ducted Ducted Capacity Rated* BTU/h 36,000 36,000 36,000 42,000 42,000 42,000...
Page 10 kcal/h = kW o 860 Conversion formula: BTU/h = kW o 3412 /min o 35.31 Service Ref. MXZ-8C48NAHZ MXZ-8C48NA Indoor type Non-Ducted Ducted Non-Ducted Ducted Capacity Rated* BTU/h 48,000 48,000 48,000 48,000 48,000 48,000 Rated power consumption* 4,000 4,525 5,050 4,000 4,525 5,050...
Page 11 3-2. BRANCH BOX: PAC-MKA50BC PAC-MKA30BC PAC-MKA50BC PAC-MKA30BC Model name Connectable number of indoor units Maximum 5 Maximum 3 Single phase, 208/230 V, 60 Hz Power supply 0.003 Input 0.05 Running current Galvanized sheets External finish Width in (mm) 17-23/32 (450) Depth in (mm) 11-1/32 (280)
Page 12: Data
DATA 4-1. COOLING AND HEATING CAPACITY AND CHARACTERISTICS 4-1-1. Method for obtaining system cooling and heating capacity: To obtain the system cooling and heating capacity and the electrical characteristics of the outdoor unit, first add up the ratings of all the indoor units connected to the outdoor unit (see table below), and then use this total to find the standard capacity with the help of the tables on 4-3.
Page 13 4-2. STANDARD OPERATION DATA (REFERENCE DATA) Outdoor unit model Operation MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NA/NAHZ Indoor Ambient 80°F / 67°F 70°F / 60°F 80°F / 67°F 70°F / 60°F 80°F / 67°F 70°F / 60°F DB/WB temperature Outdoor 95°F / 75°F 47°F / 43°F 95°F / 75°F...
Page 14 Before calculating the sum of total capacity of indoor units, please convert the value into the kW model capacity following the formula on "4-1-1. Method for obtaining system cooling and heating capacity". 4-3-1. MXZ-4C36NAHZ <cooling> Total capacity of indoor units (kBTU/h)
Page 15 4-3-2. MXZ-4C36NAHZ <heating> Total capacity of indoor units (kBTU/h) Total capacity of indoor units (kBTU/h) Total capacity of indoor units (kBTU/h) OCH573...
Page 16 4-3-3. MXZ-5C42NAHZ <cooling> 45.0 40.0 35.0 30.0 25.0 20.0 15.0 10.0 Total capacity of indoor units (kBTU/h) Total capacity of indoor units (kBTU/h) 25.0 20.0 15.0 10.0 Total capacity of indoor units (kBTU/h) OCH573...
Page 17 4-3-4. MXZ-5C42NAHZ <heating> 60.0 50.0 40.0 30.0 20.0 10.0 Total capacity of indoor units (kBTU/h) Total capacity of indoor units (kBTU/h) 30.0 25.0 20.0 15.0 10.0 Total capacity of indoor units (kBTU/h) OCH573...
Page 18 4-3-5. MXZ-8C48NA MXZ-8C48NAHZ <cooling> 60.0 50.0 40.0 30.0 20.0 10.0 Total capacity of indoor units (kBTU/h) Total capacity of indoor units (kBTU/h) 30.0 25.0 20.0 15.0 10.0 Total capacity of indoor units (kBTU/h) OCH573...
Page 19 4-3-6. MXZ-8C48NA MXZ-8C48NAHZ <heating> 60.0 50.0 40.0 30.0 20.0 10.0 Total capacity of indoor units (kBTU/h) Total capacity of indoor units (kBTU/h) 30.0 25.0 20.0 15.0 10.0 Total capacity of indoor units (kBTU/h) OCH573...
Page 20: Correcting Cooling And Heating Capacity
4-4. CORRECTING COOLING AND HEATING CAPACITY 4-4-1. Correcting Changes in Air Conditions (1)To obtain the system cooling and heating capacity and the electrical characteristics of the outdoor unit, first add up the ratings of all the indoor units connected to the outdoor unit (see table below), and then use this total to find the standard capacity with the help of the tables on "4-3.
Page 21 Fig. 2-3: Heating capacity Fig. 2-4: Heating input (MXZ-8C48/5C42/4C36NAHZ) (MXZ-8C48/5C42/4C36NAHZ) Indoor intake air dry-bulb temperature <:D.B.(°F W.B.)> 16.0(60.8) 21.0(69.8) 16.0(60.8) 21.0(69.8) 26.0(78.8) 26.0(78.8) Indoor intake air dry-bulb temperature <:D.B.(°F W.B.)> −25 −20 −15 −10 −5 15 (°C W.B.) −25 −20 −15 −10 −5...
Page 22 4-5. NOISE CRITERION CURVES MXZ-4C36NAHZ SPL(dB) MODE LINE MXZ-5C42NAHZ SPL(dB) MODE LINE COOLING COOLING HEATING MICROPHONE HEATING 1m(3.3ft) UNIT 1.5m (5ft) NC-70 NC-70 NC-60 NC-60 GROUND NC-50 NC-50 NC-40 NC-40 NC-30 NC-30 APPROXIMATE APPROXIMATE THRESHOLD OF THRESHOLD OF HEARING FOR...
Page 23: Outlines And Dimensions
OUTLINES AND DIMENSIONS 5-1. OUTDOOR UNIT MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NAHZ MXZ-8C48NA Unit: mm <in> OCH573...
Page 24 5-2. BRANCH BOX Unit: mm <in> PAC-MKA50BC When installing the conduit. Set the attachment to the inner side of each panel. 58 <2-9/32> SUSPENSION BOLT PITCH 320 <12-5/8> <25/32> <1-3/32> SUSPENSION BOLT : W3/8(M10) REFRIGERANT PIPE FLARED CONNECTION TO OUTDOOR UNIT LIQUID PIPE 1/4F 1/4F...
Page 25: Wiring Diagram
WIRING DIAGRAM 6-1. OUTDOOR UNIT MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NAHZ OCH573...
Page 26 MXZ-8C48NA OCH573...
Page 27 6-2. BRANCH BOX PAC-MKA50BC PAC-MKA30BC OCH573...
Page 28: Necessary Conditions For System Construction
NECESSARY CONDITIONS FOR SYSTEM CONSTRUCTION 7-1. TRANSMISSION SYSTEM SETUP OCH573...
Page 29: Refrigerant System Diagram
7-2. REFRIGERANT SYSTEM DIAGRAM MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NAHZ Thermistor(TH-A–E) Thermistor(TH7) <Gas pipe temperature> Check valve <Ambient> Service port 4-Way Valve (21S4) Strainer Room temperature High pressure Ball valve thermistor Oil separator switch(63H) Solenoid valve(SV1) (TH1 or RT11) <Bypass> Capillary Strainer Distributor...
Page 30 7-3. TYPICAL CONTROL SYSTEM IMPORTANT: TB3A TB3A TB15 Branch Box Make sure that the current leakage breaker is one compatible with higher (01) (51) harmonics. Always use a current leakage breaker that is compatible with higher harmon- TB3B TB3A TB15 M1 M2 S M1 M2 S ics as this unit is equipped with an inverter.
Page 31 ( 5) Group setting 1 MA group or M-NET group setting cannot be set. 2 Indoor units of CITY MULTI series cannot be connected to the branch boxes or outdoor unit. (6) Restricted functions • The following functions of system controller cannot be used. •...
Page 32: Troubleshooting
TROUBLESHOOTING 8-1. TROUBLESHOOTING <Check code displayed by self-diagnosis and actions to be taken for service (summary)> Present and past check codes are logged, and they can be displayed on the wired remote controller and multi controller circuit board of outdoor unit. Actions to be taken for service, which depends on whether or not the trouble is reoccurring in the field, are summarized in the table below.
Page 33 8-2. CHECK POINTS FOR TEST RUN 8-2-1. Procedures before test run (1) Before a test run, make sure that the following work is completed. • Installation related : Make sure that the panel of cassette type and electrical wiring are done. Otherwise electrical functions like auto vane will not operate normally.
Page 34 8-2-1-2. Test run for wired remote controller <PAR-31MAA> MENU RETURN SELECT ON/OFF Function buttons Select "Service" from the Main menu, and press the button. Test run Input maintenance info. Function setting Check Self check Select "Test run" with the F1 or F2 button, and press the button.
Page 35 8-2-2. Special Function Operation and Settings (for M-NET Remote Controller) • It is necessary to perform “group settings” and “paired settings” at making group settings of different refrigerant systems (multiple outdoor unit). (A) Group settings: Enter the indoor unit controlled by the remote controller, check the content of entries, and clear entries, etc. (B) Paired settings: Used to set the linked operation of a Lossnay unit.
Page 36 (2) Address check: Refer to section (1) regarding address entry. a) In making group settings: • Turn off the remote controller: Press the remote controller's ON/OFF button to stop operation (the indicator light will go off). • Locate the indoor unit address display mode: Press the FILTER and k buttons on the remote controller simultaneously and hold for 2 seconds.
Page 37 8-3. CHECK POINTS FOR TEST RUN 8-3-1. Procedures before test run (1) Before a test run, make sure that the following work is completed. • Installation related : Make sure that the panel of cassette type and electrical wiring are done. Otherwise electrical functions like auto vane will not operate normally.
Page 38 (2) Using SW3 in outdoor unit In case of the test run from outdoor unit, all indoor units operate. Therefore, you cannot detect any erroneous con- nection of refrigerant pipes and the connecting wires. If it aims at detection of any erroneous connection, be sure to carry out the test run from remote controller with reference to "(1) Using remote controller."...
Page 39 8-3-3. Countermeasures for Error During Test Run • If a problem occurs during test run, a code number will appear on the remote controller (or LED on the outdoor unit), and the air conditioning system will automatically cease operating. Determine the nature of the abnormality and apply corrective measures. Detected Unit Check Remarks...
Page 40: Serial Communication Error
8-4. SELF-DIAGNOSIS ACTION BY FLOWCHART Check code Serial communication error 0403 Abnormal points and detection methods Causes and check points Abnormal if serial communication between the outdoor controller board Wire breakage or contact failure of connector CN2 or and outdoor power board is defective. Malfunction of power board communication circuit on outdoor controller board Malfunction of communication circuit on outdoor...
Page 41 Check code Compressor temperature trouble 1102 Chart 1 of 2 Abnormal points and detection methods Causes and check points (1) Abnormal if TH4 falls into following temperature conditions; Malfunction of stop valve Over-heated compressor operation caused by ●exceeds 230°F [110 ] continuously for 5 minutes shortage of refrigerant ●exceeds 257°F [125 ] Defective thermistor...
Page 42 Check code Compressor temperature trouble 1102 Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Disconnect the thermistor wiring to check the resistance.
Page 43 Check code High pressure trouble 1302 Chart 1 of 4 Abnormal points and detection methods Causes and check points (1) High pressure abnormality (63H operation) Defective operation of stop valve (not fully open) Abnormal if 63H operates(*) during compressor operation. (*4.15 MPa) Clogged or broken pipe Malfunction or locked outdoor fan motor (2) High pressure abnormality (63HS detected)
Page 44 Check code High pressure trouble 1302 Chart 2 of 4 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Is the indoor unit filter clogged? Clean the filter.
Page 45 Check code High pressure trouble 1302 Chart 3 of 4 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Is there a resistance detected? Replace the TH7. Disconnect the indoor LEV wiring to check the resistance.
Page 46 Check code High pressure trouble 1302 Chart 4 of 4 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Is there a resistance detected? Replace the SV1. Is the connector for outdoor controller board 63H disconnected or Reconnect the connector or connect it tightly.
Page 47 Check code Superheat due to low discharge temperature trouble 1500 Chart 1 of 2 Abnormal points and detection methods Causes and check points Abnormal if the discharge superheat is continuously detected less than Disconnection or loose connection of TH4 or equal to 5°F [−15 ]* for 5 minutes even though the indoor LEV has Defective holder of TH4 minimum open pulse after the compressor starts operating for 10 minutes.
Page 48 Check code Superheat due to low discharge temperature trouble 1500 Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Is there a resistance detected? Replace the indoor LEV.
Page 49: Cooling
Check code Refrigerant shortage trouble 1501 Chart 1 of 2 Abnormal points and detection methods Causes and check points (1) Abnormal when all of the following conditions are satisfied: Defective operation of stop valve (not fully open) 1. The compressor is operating in HEAT mode. Defective thermistor 2.
Page 50 Check code Refrigerant shortage trouble 1501 Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Is there a resistance detected? Replace the thermistor. Check the 63HS voltage.
Page 51: Blocked Valve In Cooling Mode
Check code Blocked valve in cooling mode 1501 Abnormal points and detection methods Causes and check points Abnormal if stop valve is blocked during cooling operation. Outdoor liquid/gas valve is blocked. Mulfunction of outdoor LEV (LEV-A) (blockage) Abnormal when both of the following temperature conditions are satisfied for 20 minutes or more during cooling operation.
Page 52: Indoor Hex Freezing Protection
Check code Indoor HEX freezing protection 1503 Abnormal points and detection methods Causes and check points The purpose of the check code is to prevent indoor unit from freezing or Wrong piping connection between indoor unit and dew condensation which is caused when a refrigerant keeps flowing into branch box the unit in STOP.
Page 53: Way Valve Trouble In Heating Mode
Check code 4-way valve trouble in heating mode 1508 Abnormal points and detection methods Causes and check points Abnormal if 4-way valve does not operate during heating operation. 4-way valve failure Disconnection or failure of 4-way valve coil Abnormal when any of the following temperature conditions is satisfied for Clogged drain pipe 3 minutes or more during heating operation Disconnection or loose connection of connectors...
Page 54: Heating
Check code Water leakage 2500 Chart 1 of 2 Abnormal points and detection methods Causes and check points Abnormal if drain sensor or float switch detects to be in the water during Reverse connection of extended piping (when cooling or dry operation. connecting multiple units) Reverse connection of indoor/ outdoor connector To release this abnormality, reset the power (turn OFF and ON).
Page 55: Och573
Check code Check code Water leakage 2500 Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards Diagnosis Remedy Continued from the previous page ●Is there an adhesion of water drops on the drain sensor? Solve the problem.
Page 56: Och573
Check code <Drain sensor models> Drain overflow protection 2502 Chart 1 of 3 Abnormal points and detection methods Causes and check points Drain pump (DP) 1 Malfunction of drain pump 1Let drain sensor self-heated, and if temperature rises slightly, as 2 Defective drain suspensive abnormality operation stops and changes to protect mode of Clogged drain pump...
Page 57: Och573
Check code <Drain sensor models> Drain overflow protection 2502 Chart 2 of 3 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Is the resistance of drain Replace the drain sensor.
Page 58: Och573
Check code <Drain sensor models> Drain overflow protection 2502 Chart 3 of 3 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Check the voltage on both ends of the branch connector.
Page 59: Och573
Check code <Float switch models> Drain overflow protection 2502 Chart 1 of 2 Abnormal points and detection methods Causes and check points Drain pump (DP) 1 Malfunction of drain pump 1Judge whether the sensor is in the water or in the air by turning the float 2 Defective drain switch ON/OFF.
Page 60: Och573
Check code Check code <Float switch models> Drain overflow protection 2502 Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Is there a difficulty on the Solve the problem.
Page 61: Och573
Check code <Drain sensor models> Drain senor abnormality 2503 Abnormal points and detection methods Causes and check points <Drain sensor models> Contact failure of connector CN31 Abnormal if drain sensor detects to be short/ open . Characteristic defect of thermistor Breakage or contact failure of drain sensor wiring.
Page 62: Och573
Check code Compressor current interruption (Locked compressor) 4100 Chart 1 of 2 Abnormal points and detection methods Causes and check points Abnormal if overcurrent of DC bus or compressor is detected 30 seconds Closed stop valve after the compressor starts operating. Decrease of power supply voltage Looseness, disconnection or converse of compressor wiring connection...
Page 63: Och573
Check code Compressor current interruption (Locked compressor) 4100 Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Set the model selection switch correctly, Are they set properly? then restart.
Page 64: Och573
Check code Compressor overcurrent interruption 4210 Chart 1 of 2 Abnormal points and detection methods Causes and check points Abnormal if overcurrent of DC or the compressor is detected within 30 Closed outdoor stop valve seconds after the compressor starts operating. Decrease of power supply voltage Looseness, disconnection or reverse phase of compressor wiring connection...
Page 65: Och573
Check code Compressor overcurrent interruption 4210 Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Connect the compressor wiring (U, V and Are they connected properly? W phase) properly, then turn the power back ON.
Page 66: Och573
Check code Voltage shortage/Overvoltage/PAM error/L1 open-phase/ 4220 Power synchronization signal error Chart 1 of 2 Abnormal points and detection methods Causes and check points Abnormal if any of following symptoms are detected; Decrease/increase of power supply voltage, or T open-phase ●Decrease of DC bus voltage to 200V Disconnection of compressor wiring ●Increase of DC bus voltage to 400V...
Page 67: Noise
Check code Voltage shortage/Overvoltage/PAM error/L1 open-phase/ 4220 Power synchronization signal error Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. The black square (■) indicates a switch position. Diagnosis Remedy Continued from the previous page...
Page 68: Och573
Check code Heat sink temperature trouble 4230 Abnormal points and detection methods Causes and check points Abnormal if TH8 detects a temperature outside the specified range during Blocked outdoor fan compressor operation. Malfunction of outdoor fan motor Blocked airflow path Thermistor <Heat sink>...
Page 69: Och573
Check code Power module trouble 4250 Abnormal points and detection methods Causes and check points Abnormal if overcurrent of DC bus or compressor is detected 30seconds Closed outdoor stop valve after the compressor starts operating. To determine the source of Decrease of power supply voltage abnormality, either the compressor or the power module, drive the power Disconnection, looseness or conversed connection...
Page 70 Check code Rotational frequency of outdoor fan motor trouble 4400 Abnormal points and detection methods Causes and check points Abnormal if no rotational frequency is detected, or detected a value Malfunction of fan motor outside the specified range during fan motor operation. Disconnection of CNF connector Defective outdoor controller board ●Diagnosis of defectives...
Page 71: Compressor Temperature Thermistor (Th4) Open/Short
Check code Compressor temperature thermistor (TH4) open/short 5101 <Detected in outdoor unit> Abnormal points and detection methods Causes and check points Abnormal if TH4 detects to be open/short. Disconnection or contact failure of connectors (The open/short detection is disabled for 10 minutes after compressor Characteristic defect of thermistor starts, during defrosting operation, or for 10 minutes after returning from Defective outdoor controller board...
Page 72: Suction Pipe Temperature Thermistor (Th6) Open/Short
Check code Suction pipe temperature thermistor (TH6) open/short 5102 <Detected in outdoor unit> Abnormal points and detection methods Causes and check points Abnormal if TH6 detects to be open/short. Disconnection or contact failure of connectors (The open/short detection is disabled during 10 seconds to 10 minutes. Characteristic defect of thermistor after compressor starts, during defrosting operation, or for 10 minutes after Defective outdoor controller board...
Page 73 Air inlet thermistor trouble (TH21) Check code Liquid pipe temperature thermistor trouble (TH22) 5101, 5102, 5103 Gas pipe temperature thermistor trouble (TH23) <Detected in indoor unit> Abnormal points and detection methods Causes and check points Abnormal if any of the following thermistor detected to be open/ short. Contact failure of connectors Characteristic defect of thermistor TH21: Air inlet thermistor...
Page 74: Outdoor Liquid Pipe Temperature Thermistor (Th3) Open/Short
Check code Outdoor liquid pipe temperature thermistor (TH3) open/short 5105 Abnormal points and detection methods Causes and check points Abnormal if TH3 detects to be open/short. Disconnection or contact failure of connectors (The open/short detection is disabled during 10 seconds to 10 minutes. Characteristic defect of thermistor after compressor starts, during defrosting operation, or for 10 minutes after Defective outdoor controller board...
Page 75: Ambient Thermistor (Th7) Open/Short
Check code Ambient thermistor (TH7) open/short 5106 Abnormal points and detection methods Causes and check points Abnormal if TH7 detects to be open/short Disconnection or contact failure of connectors Open: −40°F [-40 ] or less Characteristic defect of thermistor Short: 194°F [90 ] or more TH7: Thermistor <Ambient>...
Page 76: Hic Pipe Temperature Thermistor (Th2) Open/Short
Check code HIC pipe temperature thermistor (TH2) open/short 5109 Abnormal points and detection methods Causes and check points Abnormal if TH2 detects to be open/short. Disconnection or contact failure of connectors Open: –40°F [–40 ] or less Characteristic defect of thermistor Short: 194°F [90 ] or more TH2: Thermistor <HIC pipe>...
Page 77 Check code Heat sink temperature thermistor(TH8) open/short 5110 Abnormal points and detection methods Causes and check points Abnormal if TH8 detects to be open/short. Disconnection or contact failure of connectors Open: −31.2°F [−35.1 ] or less Characteristic defect of thermistor Short: 338.5°F [170.3 ] or more Defective outdoor controller board TH8: Thermistor <Heat sink>...
Page 78 Check code High-pressure sensor (63HS) trouble 5201 Abnormal points and detection methods Causes and check points When the detected pressure in the high-pressure sensor is 1 kgf/F [14.2 Defective high-pressure sensor PSIG] or less during operation, the compressor stops operation and Decrease of internal pressure caused by gas enters into an anti-restart mode for 3 minutes.
Page 79 Check code Low-pressure sensor (63LS) trouble 5202 Abnormal points and detection methods Causes and check points When the detected pressure in the low-pressure sensor is −2.3kgf/F Defective low-pressure sensor Decrease of internal pressure caused by gas [−32.7 PSIG] or less, or 23.1kgf/F [328.6 PSIG] or more during leakage operation, the compressor stops operation with a check code <5202>.
Page 80 Check code Primary current error 5300 Abnormal points and detection methods Causes and check points Abnormal if the detected current sensor input value (primary current) Decrease/ trouble of power supply voltage during compressor operation is outside the specified range. Disconnection of compressor wiring Input sensor trouble on outdoor power board ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting...
Page 81: Contact Failure Of Drain Float Switch
Check code Models equipped with the float switch Contact failure of drain float switch 5701 Abnormal points and detection methods Causes and check points <Models equipped with the float switch> Contact failure of connector CN4F Abnormal if the connector on the drain float switch side CN4F is detected Defective indoor controller board to be disconnected.
Page 82: Duplex Address Error
Check code Duplex address error 6600 Abnormal points and detection methods Causes and check points Abnormal if 2 or more units with the same address are existing. There are 2 units or more with the same address in their controller among outdoor unit, indoor unit, Fresh Master, Lossnay or remote controller Noise interference on indoor/outdoor connectors ●Diagnosis of defectives...
Page 83 Check code Transmission processor H/W error 6602 Abnormal points and detection methods Causes and check points Abnormal if the transmission line shows "1" although the transmission A transmitting data collision occurred because of a processor transmitted "0". wiring work or polarity change has performed while the power is ON on either of the indoor/outdoor unit, Fresh Master or Lossnay Malfunction of transmitting circuit on transmission...
Page 84: Transmission Bus Busy Error
Check code Transmission bus BUSY error 6603 Abnormal points and detection methods Causes and check points Over error by collision The transmission processor is unable to transmit due Abnormal if no-transmission status caused by a transmitting data to a short-cycle voltage such as noise is mixed on collision is consecutive for 8 to 10minutes.
Page 85: Signal Communication Error With Transmission Processor
Check code Signal communication error with transmission processor 6606 Abnormal points and detection methods Causes and check points Abnormal if the data of unit/transmission processor were not normally Accidental disturbance such as noise or lightning transmitted. surge Hardware malfunction of transmission processor Abnormal if the address transmission from the unit processor was not normally transmitted.
Page 86 Check code No ACK error 6607 Chart 1 of 4 Abnormal points and detection methods Causes and check points Represents a common error detection The previous address unit does not exist since An abnormality detected by the sending side controller when receiving the address switch was changed while in electric no ACK from the receiving side, though signal was once sent.
Page 87 Check code No ACK error 6607 Chart 2 of 4 Abnormal points and detection methods Causes and check points While the indoor unit is operating with multi refrigerant system Fresh Master, an abnormality The cause of displayed address and attribute is on the Fresh Master is detected when the indoor unit transmits signal side to the remote controller while the outdoor unit with...
Page 88 Check code No ACK error 6607 Chart 3 of 4 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Procedure 1: Turn the power OFF of indoor/outdoor unit, Fresh Master, Lossnay and remote controller simultaneously for 2 minutes or more, then turn the power back ON.
Page 89 Check code No ACK error 6607 Chart 4 of 4 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards. Diagnosis Remedy Continued from the previous page Apply the correct kind of transmission line, Is the correct kind of transmission then perform the procedure 1.
Page 90: No Response Frame Error
Check code No response frame error 6608 Abnormal points and detection methods Causes and check points Abnormal if receiving no response command while already received ACK. Continuous failure of transmission due to noise etc The sending side searches the error in 30 seconds interval for 6 times Decline of transmission voltage/signal caused by continuously.
Page 91 Check code MA communication receive error 6831 6834 Chart 1 of 2 Abnormal points and detection methods Causes and check points Detected in remote controller or indoor unit: Contact failure of remote controller wirings Irregular Wiring When the main or sub remote controller cannot receive signal from (A wiring length, number of connecting remote indoor unit which has the "0"...
Page 92 Check code MA communication receive error 6831 6834 Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards Diagnosis Remedy Continued from the previous page Refer to the chapter "Electrical Work".
Page 93 Check code MA communication send error 6832 6833 Chart 1 of 2 Abnormal points and detection methods Causes and check points Detected in remote controller or indoor unit. There are 2 remote controllers set as main. Malfunction of remote controller sending/receiving circuit Malfunction of sending/receiving circuit on indoor controller board...
Page 94 Check code MA communication send error 6832 6833 Chart 2 of 2 ●Diagnosis of defectives Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards Diagnosis Remedy Continued from the previous page Refer to the chapter "Electrical Work".
Page 95: Total Capacity Error
Check code Total capacity error 7100 Abnormal points and detection methods Causes and check points When the total of the number on connected indoor unit model names The total of number on connected indoor unit model exceeds the specified capacity level (130% of the number on the outdoor names exceeds the specified capacity level: unit model name), a check code <7100>...
Page 96: Capacity Code Error
Check code Capacity code error 7101 Abnormal points and detection methods Causes and check points When the capacity of connected indoor unit is over, a check code <7101> The model name of connected indoor unit (model code) is displayed. is read as incompatible. The connectable indoor units are: ·P6 to P36 model (code 4 to 20) ●Diagnosis of defectives...
Page 97: Connecting Excessive Number Of Units And Branch Boxes
Check code Connecting excessive number of units and branch boxes 7102 Abnormal points and detection methods Causes and check points When the connected indoor units or branch boxes exceed the limit, a Connecting more indoor units and branch boxes than check code <7102>...
Page 98: Address Setting Error
Check code Address setting error 7105 Abnormal points and detection methods Causes and check points The address setting of outdoor unit is wrong. Wrongly set address of indoor unit The outdoor unit is not set in 000, or in the range of 51 to 100.
Page 99 Check code Incompatible unit combination error 7130 Abnormal points and detection methods Causes and check points When the connected indoor unit is not connectable with the outdoor unit, Connecting indoor unit (s) which is not authorized to the outdoor unit detects the error at start-up. connect to the outdoor unit.
Page 100: Troubleshooting By Inferior Phenomena
8-5. TROUBLESHOOTING BY INFERIOR PHENOMENA Phenomena Factor Countermeasure 1. Remote controller display works 1 Refrigerant shortage 1 If refrigerant leaks, discharging tempera- normally and the unit performs cool- ture rises and LEV opening increases. ing operation, however, the capacity Inspect leakage by checking the tem- cannot be fully obtained.
Page 101 8-6. OUTDOOR UNIT INPUT/OUTPUT CONNECTOR State (CN51) A Distant control board E Lamp power supply B Relay circuit F Procure locally C External output adapter (PAC-SA88HA-E) G Max. 10 m CN51 D Outdoor unit control board : Error display lamp : Compressor operation lamp X, Y: Relay (Coil standard of 0.9W or less for 12 V DC) X, Y: Relay (1mA DC)
Page 102 8-7. HOW TO CHECK THE PARTS OUTDOOR UNIT: MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NAHZ MXZ-8C48NA Parts name Check points Thermistor (TH3) Disconnect the connector then measure the resistance with a tester. (At the ambient temperature 50 to 80˚F [10 to 30 :]) <Outdoor liquid pipe>...
Page 103 Check method of DC fan motor (fan motor / outdoor multi controller circuit board) Notes 1. High voltage is applied to the connecter (CNF1, 2) for the fan motor. Pay attention to the service. 2. Do not pull out the connector (CNF1, 2) for the motor with the power supply on. (It causes trouble of the outdoor multi controller circuit board and fan motor.) Self check...
Page 104 Check method of multi controller circuit board Multi controller circuit board check Fuse check Check the fuse on multi controller circuit board Yes (blow) Replace multi controller circuit board and fan motor. Did the fuse (F500) blow? See DC fan check. Yes (blow) Did the fuse (F1 and F2) blow? Check the SV1, SV2, SS and 21S4 and wiring.
Page 105 Check method of power circuit board Power circuit board check Note: To check the voltage of the parts on this board with a tester is difficult due to its location. Test points are limited. Is the voltage of main incoming power •...
Page 106 Check method of M-NET power circuit board M-NET power circuit board check * To check the voltage of the parts on this board with a tester is difficult due to its location. Test points are limited. Check the voltage between M1 and M2 on the transmission terminal block TB3.
Page 107 8-8. HOW TO CHECK THE COMPONENTS <Thermistor Characteristic Graph> Low temperature thermistors • Thermistor <HIC pipe> (TH2) • Thermistor <Outdoor liquid pipe> (TH3) • Thermistor <Suction pipe> (TH6) • Thermistor <Ambient> (TH7) Thermistor R0 = 15 k" ± 3 % B constant = 3480 ±...
Page 108 BRANCH BOX : PAC-MKA50BC PAC-MKA30BC Parts name Check points Disconnect the connector then measure the resistance with a tester. Thermistor (TH-A–E) (At the ambient temperature 50 to 86°F [10 to 30:]) <Gas pipe> Normal Abnormal 4.3 to 9.6k" Open or short Disconnect the connector then measure the resistance with a tester.
Page 109 Linear expansion valve (LEV) in Branch box (1) Operation summary of the linear expansion valve • Linear expansion valve open/close through stepping motor after receiving the pulse signal from the branch box controller board. • Valve position can be changed in proportion to the number of pulse signal. <Connection between the branch box controller board and the linear expansion valve>...
Page 110 (3) How to attach and detach the coil of linear expansion valve <Composition> Linear expansion valve is separable into the main body and the coil as shown in the diagram below. Main body Coil Lead wire Stopper <How to detach the coil> Hold the lower part of the main body (shown as A) firmly so that the main body does not move and detach the coil by pulling it upward.
Page 111 Troubleshooting Check point Corrective measure Problem Locked expansion Replace the linear If the linear expansion valve becomes locked and the motor is still operating, valve expansion valve. the motor will emit a clicking noise and will not function. This clicking noise indicates an abnormality.
Page 112 8-9. TEST POINT DIAGRAM Outdoor multi controller circuit board MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NAHZ MXZ-8C48NA <CAUTION> TEST POINT 1 is high voltage. CN51 External signal Model selection Pump down Test run Forced defrost Model selection output CN102 Connect to the M-P.B (M-NET power circuit board)
Page 113 Outdoor power circuit board Brief Check of POWER MODULE Usually, they are in a state of being short-circuited if they are broken. MXZ-4C36NAHZ Measure the resistance in the following points (connectors, etc.). MXZ-5C42NAHZ If they are short-circuited, it means that they are broken.
Page 114 M-NET power circuit board Connect to the outdoor multi MXZ-4C36NAHZ controller circuit board (CN102) 1–2: 24–30 V DC MXZ-5C42NAHZ 3–4: 24–30 V DC MXZ-8C48NAHZ MXZ-8C48NA Connect to the electrical parts box Connect to the outdoor power circuit board (CNAC1) 1–3: 220–240 V AC...
Page 115 Branch box controller board PAC-MKA50BC PAC-MKA30BC TH-A to E Connect to LEV-A to E Thermistor-A to E Connect to LEV-A to E TH-D and E for PAC-MKA50BC only LEV-D and E for PAC-MKA50BC only CN3M Connected to the terminal block (TB5) (M-NET transmission con- necting wire) 24–30 V DC (non polar)
Page 116 8-10. INTERNAL SWITCH FUNCTION TABLE (1) Function of switches MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NAHZ MXZ-8C48NA ■ The black square ( ) indicates a switch position. Continue to the next page OCH573...
Page 117 OCH573...
Page 118 PAC-MKA50BC PAC-MKA30BC ■ The black square ( ) indicates a switch position. OCH573...
Page 119 (2) Function of connector MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NAHZ MXZ-8C48NA Action by Pin short operation Types Connector Function Effective timing Pin 1-2 Short Pin 2-3 Short LEV opening function Connector CN31 Open a little bit Normal When power supply ON (at start-up)
Page 120 SW:setting 0..OFF 8-11. OUTDOOR UNIT FUNCTIONS 1..ON OCH573...
Page 121 OCH573...
Page 122 OCH573...
Page 123 OCH573...
Page 124 OCH573...
Page 125 OCH573...
Page 126 OCH573...
Page 127 OCH573...
Page 128 8-12. BRANCH BOX FUNCTIONS <Branch box unit operation monitor function> [When option part ‘A-Control Service Tool (PAC-SK52ST)’ is connected to branch box controller board (CNM)] Digital indicator LED1 displays 2 digit number or code to inform operation condition and the meaning of check code by controlling DIP SW2 on ‘A-Control Service Tool’.
Page 129 The black square (■) indicates a switch position. SW2 setting SW5 setting* Display detail Explanation for display Unit ― ― Common Not used Individual unit Actual opening pulse 0 to 500 of LEV (When it is 100 pulse or more, it displays a hundredth, 2 3 4 5 6 (Direct-operated tens, and unit digit by turns.)
Page 130 The black square (■) indicates a switch position. SW2 setting Display detail Explanation for display Unit SW5 setting* ― ― Common Not used Individual unit Indoor thermistor −38 to 190 [−39 to 88] <pipe temperature/ 2 3 4 5 6 (When the temperature is 0 or less, "−"...
Page 131 8-13. SELECTING FUNCTIONS USING THE REMOTE CONTROLLER Each function can be set as necessary using the remote controller. The setting of function for each unit can only be done by the remote controller. Select function available from the <Table 1> . (1) Functions available when setting the unit number to 00 Note that the functions in the table below are available only when P-series indoor unit and the wired remote controller is used.
Page 132: Precautions Against Refrigerant Leakage
PRECAUTIONS AGAINST REFRIGERANT LEAKAGE 9-1. PRECAUTIONS AGAINST REFRIGERANT LEAKAGE 9-1-1. Introduction R410A refrigerant of this air conditioner is non-toxic and non-flammable but leaking of large amount from an indoor unit into the room where the unit is installed may be deleterious. To prevent possible injury, the rooms should be large enough to keep the R410A concentration specified by ISO 5149-1 as follows.
Page 133: Disassembly Procedure
DISASSEMBLY PROCEDURE 10-1. OUTDOOR UNIT Note: Turn OFF the power supply before disassembly. MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NAHZ OPERATING PROCEDURE PHOTOS & ILLUSTRATION 1. Removing the service panel and top panel Top panel fixing screws Top panel Photo 1 (1) Remove 3 service panel fixing screws (5 × 12), then slide the hook on the right downward to remove the service panel.
Page 134 From the previous page. OPERATING PROCEDURE PHOTOS & ILLUSTRATION Photo 5 (6) Remove 2 electrical parts box fixing screws (4 × 10), then Electrical parts box detach the electrical parts box by pulling it upward. The electrical parts box is fixed with 2 hooks on the left and 1 hook on the right.
Page 135 PHOTOS OPERATING PROCEDURE 6. Removing the thermistor <Outdoor liquid pipe> (TH3) and Photo 9 thermistor <Compressor> (TH4), thermistor <HIC pipe> (TH2) (1) Remove the service panel. (See Photo 1) (2) Disconnect the connectors, TH3 (white) and TH4 (white), TH2 (black) on the multi controller circuit board in the elec- trical parts box.
Page 136 OPERATING PROCEDURE PHOTOS 9. Removing bypass valve coil (SV1, SV2) and bypass valve Photo 11 (1) Remove the service panel. (See Photo 1) Electronic expansion Electronic expansion Bypass valve (2) Remove the top panel. (See Photo 1) valve coil (LEV-B) valve coil (LEV-A) coil fixing screw (3) Remove the cover panel (front).
Page 137 OPERATING PROCEDURE PHOTOS 13. Removing the compressor (MC) Photo 13 Valve bed fixing screws (1) Remove the service panel. (See Photo 1) (2) Remove the top panel. (See Photo 1) Valve bed (3) Remove 2 front cover panel fixing screws (5 × 12) and remove the front cover panel.
Page 138 PHOTOS OPERATING PROCEDURE 15. Removing the reactor (DCL) Figure 3 (1) Remove the service panel. (See Photo 1) Electrical parts box (2) Remove the top panel. (See Photo 1) (3) Remove the electrical parts box (See photo 5) (4) Remove 4 screws for reactor (4 x 10) to remove the reac- tor.
Page 139 MXZ-8C48NA Note: Turn OFF the power supply before disassembly. PHOTOS & ILLUSTRATION OPERATING PROCEDURE Figure 1 1. Removing the service panel and top panel Top panel fixing screws Top panel (1) Remove 3 service panel fixing screws (5 × 12) and slide Service panel the hook on the right downward to remove the service fixing screw...
Page 140 From the previous page. PHOTOS & ILLUSTRATION OPERATING PROCEDURE Photo 4 (6) Remove 2 electrical parts box fixing screws (4 × 10) Electrical parts box and detach the electrical parts box by pulling it upward. The electrical parts box is fixed with 2 hooks on the left and 1 hook on the right.
Page 141 PHOTOS OPERATING PROCEDURE Photo 8 6. Removing the thermistor <Outdoor liquid pipe> (TH3) and thermistor <Compressor> (TH4), thermistor <HIC pipe> (TH2) (1) Remove the service panel. (See Figure 1) (2) Disconnect the connectors, TH3 (white) and TH4 (white), TH2 (black) on the multi controller circuit board in the elec- trical parts box.
Page 142 OPERATING PROCEDURE PHOTOS 9. Removing bypass valve coil (SV1) and bypass valve Photo 10 (1) Remove the service panel. (See Figure 1) Electronic expansion Bypass valve Bypass valve (2) Remove the top panel. (See Figure 1) valve coil (LEV-B) coil fixing screw coil (SV1) (3) Remove the cover panel (front).
Page 143 OPERATING PROCEDURE PHOTOS 13. Removing the compressor (MC) Photo 13 (1) Remove the service panel. (See Figure 1) Valve bed (2) Remove the top panel. (See Figure 1) Valve bed (3) Remove 2 front cover panel fixing screws (5 × 12) and fixing screw remove the front cover panel.
Page 144 OPERATING PROCEDURE PHOTOS Figure 4 15. Removing the reactor (DCL) (1) Remove the service panel. (See Figure 1) Electrical parts box (2) Remove the top panel. (See Figure 1) (3) Remove the electrical parts box (See photo 4) (4) Remove 4 screws for reactor (4 x 10) to remove the reac- tor.
Page 145 10-2. BRANCH BOX : PACMKA50BC PAC-MKA30BC PHOTO : PAC-MKA50BC OPERATING PROCEDURE PHOTOS Photo 1 1. Removing the controller cover and under panel (1) Remove 3 controller cover fixing screws (4 o 10) to detach Under panel fixing screws the controller cover. (See Photo 1) (2) Remove 4 under panel fixing screws (4 o 10) to remove the under panel.
Page 146 OPERATING PROCEDURE PHOTOS Photo 3 3. Removing the LEV coil (LEV-A–E*) (1) Remove the controller cover. (See Photo 1) Rubber mount Bands Header assy (2) Remove the under cover. (See Photo 1) Bands LEV assy (3) Remove 8 insulations, then remove 9 pipe cover fixing screws (4 x 10).
Page 147 OPERATING PROCEDURE PHOTOS 5. Removing the LEV assy Photo 5-1 (1) Remove the controller cover. (See Photo 1) LEV assy (2) Remove the under panel. (See Photo 1) (3) Remove 8 the insulations, then remove 9 pipe cover fixing screws (4 x 10). (See Photo 2-1) (4) Loosen the side clamps, then disconnect the LEV connec- tors on the controller board.
Page 148 HEAD OFFICE : TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO100-8310, JAPAN cCopyright 2014 MITSUBISHI ELECTRIC CORPORATION Distributed in Aug. 2014 No.OCH573 New publication, effective Aug. 2014 Made in Japan Specifications are subject to change without notice.

This manual is also suitable for:

Pac-mka30bc Mxz-5c42nahz Mxz-8c48nahz Mxz-8c48na Pac-mka50bc

Mitsubishi Electric MXZ-4C36NAHZ Service Manual

Pac-Mka50Bc

8-3-3. Countermeasures for Error During Test Run

Quick Links

Chapters

Troubleshooting

Related Manuals for Mitsubishi Electric MXZ-4C36NAHZ

Summary of Contents for Mitsubishi Electric MXZ-4C36NAHZ

This manual is also suitable for:

Table of Contents