SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS August 2013 No.OCH545 utilized R410A TECHNICAL & SERVICE MANUAL R410A Outdoor unit Note: • This service manual [Model Name] [Service Ref.] describes technical data of SUZ-KA25VA4.TH the outdoor units. SUZ-KA25VA4 SUZ-KA35VA4.TH SUZ-KA35VA4 SUZ-KA50VA4.TH SUZ-KA50VA4 SUZ-KA60VA4.TH SUZ-KA60VA4 SUZ-KA71VA4.TH SUZ-KA71VA4...
COMBINATION OF INDOOR AND OUTDOOR UNITS INDOOR UNIT SERVICE MANUAL Outdoor unit Indoor unit Heat pump type SUZ- Service Service Ref. KA25VA4.TH KA35VA4.TH KA50VA4.TH KA60VA4.TH KA71A4.TH Manual No. SLZ-KA25VAL2.TH — — — — — — — SLZ-KA35VALR3.TH — OC320 — —...
TECHNICAL CHANGES INFORMATION FOR THE AIR CONDITIONER WITH R410A REFRIGERANT • This room air conditioner adopts an HFC refrigerant (R410A) which never destroys the ozone layer. • Pay particular attention to the following points, though the basic installation procedure is same as that for R22 conditioners. As R410A has working pressure approximate 1.6 times as high as that of R22, some special tools and piping parts/materi- als are required.
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Conversion chart of refrigerant temperature and pressure (MPa [Gauge]) R410A NOTE: The unit of pressure has been changed to MPa on the international system of units (SI unit system). The conversion factor is: 1 (MPa [Gauge]) =10.2 (kgf/cm [Gauge]) -0.5 -30 -20 -10 1.
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2. Refrigerant piping Specifications Use the refrigerant pipes that meet the following specifications. Outside diameter Wall thickness Pipe Insulation material 6.35 For liquid Heat resisting foam plastic 9.52 Specific gravity 0.045 9.52 Thickness 8 mm For gas 12.7 15.88 • Use a copper pipe or a copper-alloy seamless pipe with a thickness of 0.8 mm. Never use any pipe with a thickness less than 0.8mm, as the pressure resistance is insufficient.
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6. Pumping Down When relocating or disposing of the air conditioner, pump down the system by following the procedure below so that no refrigerant is released into the atmosphere. 1 Turn off the power supply (circuit breaker). 2 Connect the gauge manifold valve to the service port of the stop valve on the gas pipe side of the outdoor unit. 3 Fully close the stop valve on the liquid pipe side of the outdoor unit.
PARTS NAMES AND FUNCTIONS SUZ-KA25VA4.TH SUZ-KA35VA4.TH Air inlet (back and side) Piping Drain hose Air outlet Drain outlet SUZ-KA50VA4.TH Air inlet SUZ-KA60VA4.TH (back and side) SUZ-KA71VA4.TH Piping Drain hose Air outlet Drain outlet Model SUZ-KA·VA4.TH Drain socket OCH545...
OUTLINES AND DIMENSIONS SUZ-KA25VA4.TH SUZ-KA35VA4.TH Unit: mm REQUIRED SPACE Basically open 100mm or more without any obstruction in front and on both sides of the unit. Drain hole 42 Air in Air in Open two sides of left, right, or rear side. 2-Oval holes 10×21 Service panel Air out...
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SUZ-KA50VA4.TH Unit: mm SUZ-KA60VA4.TH Open as a rule REQUIRED SPACE SUZ-KA71VA4.TH 500mm or more if the front and both sides are open 417.5 Air in 100mm or more 200mm or more if there are obstacles to both sides Air in Air out 2-Oval holes 10 21 Open as a rule...
ACTUATOR CONTROL SUZ-KA25VA4.TH SUZ-KA35VA4.TH SUZ-KA50VA4.TH SUZ-KA60VA4.TH SUZ-KA71VA4.TH 9-1. 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...
SERVICE FUNCTIONS SUZ-KA25VA4.TH SUZ-KA35VA4.TH SUZ-KA50VA4.TH SUZ-KA60VA4.TH SUZ-KA71VA4.TH 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 11-6-1.) Defrost fi nish temperature (°C) Jumper wire SUZ-KA25VA4.TH SUZ-KA60VA4.TH...
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11-2. TROUBLE SHOOTING CHECK TABLE SUZ-KA25VA4.TH SUZ-KA35VA4.TH SUZ-KA50VA4.TH SUZ-KA60VA4.TH SUZ-KA71VA4.TH check Abnormal point/ Symptoms Condition Remedy Condition indication code Outdoor unit 1-time flash Outdoor power sys- Overcurrent protection cut-out operates 3 consecutive times Reconnect connector of compres- does not op- within 1 minute after the compressor gets started.
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11-3. HOW TO PROCEED "SELF-DIAGNOSIS" As this air conditioner has a function to memorize all the failures that had occured, the latest failure detail can be recalled by following the procedure below. Use this function when the check code is not displayed with wired remote controller or the remote controller at use is wireless type.
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11-3-2. Remote controller check <PAR-30MAA> <PAR-31MAA> If operations cannot be completed with the remote controller, diagnose the remote controller with this function. Select "Service" from the Main menu, and press the button. Maintenance password Remote controller check Select "Remote controller check" with the F1 or F2 button, and press button.
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11-3-3. Self-diagnosis <PAR-21MAA> When a problem occurs to the air conditioner, the indoor and outdoor units will stop, and the problem is shown in the remote controller display. [CHECK] and the refrigerant address are displayed on the temperature display, and the error code and unit number are displayed alternately as shown below.
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When the error history is reset, the display will look like the one shown below. Press the button ( in the picture in the previous page) twice ON/OFF However, if you fail to reset the error history, the error content will be displayed again. within 3 seconds.
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11-3-6. Self-diagnosis <Wireless remote controller> <In case of trouble during operation> When a malfunction occurs to air conditioner, both indoor unit and outdoor unit will stop and operation lamp blinks to inform unusual stop. < Malfunction-diagnosis method at maintenance service> [Procedure] 1.
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Refer to the following tables for details on the check codes. [Output pattern A] Beeper sounds Beep Beep Beep Beep Beep Beep Beep OPERATION · · · Repeated INDICATOR lamp flash pattern Approx. 2.5 sec. 0.5 sec. 0.5 sec. 0.5 sec. Approx.
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11-4. TROUBLE CRITERION OF MAIN PARTS SUZ-KA25VA4.TH SUZ-KA35VA4.TH SUZ-KA50VA4.TH SUZ-KA60VA4.TH SUZ-KA71VA4.TH Parts name Check method and criterion Figure Defrost thermistor (RT61) Fin temperature Measure the resistance with a tester. thermistor (RT64) Ambient temperature Refer to 11-6. “Test point diagram and voltage”, 11-6-1. (KA25/35/50) or thermistor (RT65) 11-6-2.
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11-5. TROUBLESHOOTING FLOW A How to check inverter/compressor Disconnect the connector between the compressor and the intelligent power module (KA25/35/50: IC700, KA60/71: IPM) See 11-5. “Check of open phase”. Check the voltage between terminals. Are the voltages balanced? Replace the inverter P.C. board. Check the compressor.
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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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G Check of R.V. coil First of all, measure the resistance of R.V. coil to check if the coil is defective. Refer to 11-4. In case CN721(KA25/35/50)/CN602(KA60/71) is not connected or R.V. coil is open, voltage is generated between the terminal pins of the connector although any signal is not being transmitted to R.V.
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I Check of LEV Start Turn on power supply to the outdoor unit after checking Normal LEV coil is fi xed to the LEV body securely. Is "click - click" sound heard? Or, do you feel vibration of the LEV coil with a hand? Disconnect the connector CN724 is there nor- Replace the inverter P.C.
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Electromagnetic noise enters into TV sets or radios Is the unit earthed? Earth the unit. Is the distance between the antennas Extend the distance between the antennas and and the indoor unit within 3 m, or is the the indoor unit, and/or the antennas and the distance between the antennas and the outdoor unit.
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11-6. TEST POINT DIAGRAM AND VOLTAGE 11-6-1. Inverter P.C. board SUZ-KA25VA4.TH SUZ-KA35VA4.TH SUZ-KA50VA4.TH Smoothing Smoothing R.V.coil Heater connector Smoothing capacitor capacitor (CN721) DB61 (CN722) Back side of unit capacitor (C63) (C62) (C61) 230 VAC 260 - 370 VDC Fuse (F701) T3.15AL250V Fuse (F801) 230 VAC...
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11-6-2. Inverter P.C. board SUZ-KA60VA4.TH SUZ-KA71VA4.TH Fuse (F62) Fuse (F601) R.V. coil (CN602) T2.0AL250V T3.15AL250V 230VAC 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...
DISASSEMBLY INSTRUCTIONS <"Terminal with locking mechanism" Detaching points> The terminal which has the locking mechanism can be detached as shown below. There are two types ( Refer to (1) and (2)) of the terminal with locking mechanism. The terminal without locking mechanism can be detached by pulling it out. Check the shape of the terminal before detaching.
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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 procedure 1.) (2) Disconnect the lead wire to the reactor and the following con- Screws of the nectors: relay panel <Inverter P.C.
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OPERATING PROCEDURE PHOTOS 5. Removing outdoor fan motor Photo 6 (1) Remove the cabinet and panels. (Refer to procedure 1.) Outdoor heat (2) Disconnect the following connectors: exchanger tempera- <Inverter P.C. board> ture thermistor CN932 (Fan motor) (3) Remove the propeller nut. (Photo 7) (4) Remove the propeller.
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SUZ-KA50VA4.TH NOTE: Turn OFF power supply before disassembly. OPERATING PROCEDURE PHOTOS 1. Removing the cabinet Photo 1 (1) Remove the screws of the service panel. Screws of the top 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 3 Screw of the terminal (1) Remove the cabinet and panels. (Refer to procedure 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:...
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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- perature ture thermistor and ambient temperature thermistor ture thermistor thermistor (1) Remove the cabinet and panels. (Refer to procedure 1.) (2) Disconnect the lead wire to the reactor and the following connectors: <Inverter P.C.
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SUZ-KA60VA4.TH SUZ-KA71VA4.TH NOTE: Turn OFF power supply before disassembling. OPERATING PROCEDURE PHOTOS 1. Removing the cabinet Photo 1 (1) Remove the screws of the service panel. Screws of the top 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 3 Screw of the (1) Remove the cabinet and panels. (Refer to procedure 1.) relay panel (2) Disconnect the lead wire to the reactor and the following con- Screws of the nectors: PB support...
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OPERATING PROCEDURE PHOTOS 4. Removing the discharge temperature thermistor, Photo 5 defrost thermistor, outdoor heat exchanger tempera- Outdoor heat Ambient tem- exchanger tempera- perature ture thermistor and ambient temperature thermistor ture thermistor thermistor (1) Remove the cabinet and panels. (Refer to procedure 1.) (2) Disconnect the lead wire to the reactor and the following connectors: <Inverter P.C.
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HEAD OFFICE: TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO100-8310, JAPAN Copyright 2013 MITSUBISHI ELECTRIC CORPORATION New publication, effective Aug. 2013 Distributed in Aug. 2013 No.OCH545 Specifications are subject to change without notice. Made in Japan...
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Related Links Model Number: SUZ-KA60VA4 SUZ-KA35-71VA4 Declaration of Conformity SUZ-KA25-71VA4 Service Handbook (OCH545) SUZ-KA25-71VA4 Parts Catalogue (OCB545) SUZ-KA25-71VA4 Installation Manual (RG79Y534H01)
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