SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS SPLIT-TYPE, AIR CONDITIONERS March 2009 No. OCH456 SERVICE MANUAL Indoor unit [Model names] [Service Ref.] NOTE: • This manual describes only service data of the indoor units. • RoHS compliant products have mark on the spec name plate. PKA-A12HA PKA-A18HA PKA-A12HAL PKA-A18HAL PKA-A12HA PKA-A18HA PKA-A12HAL PKA-A18HAL CONTENTS INDOOR UNIT COOL DRY AUTO FAN HEAT TEMP. 1. REFERENCE MANUAL................................... 2 2. SAFETY PRECAUTION...........
1 REFERENCE MANUAL 1-1. OUTDOOR UNIT SERVICE MANUAL Service Ref. Service Manual No. PUZ-A18/24/36NHA3 PUZ-A18/24/36NHA3-BS PUY-A12/18/24/36NHA3 PUY-A12/18/24/36NHA3-BS OCH458 OCB458 OCH426 OCB426 PUZ-HA36NHA2 1-2. TECHNICAL DATA BOOK Series (Outdoor unit) Data Book No.
2 SAFETY PRECAUTION 2-1. ALWAYS OBSERVE FOR SAFETY Before obtaining access to terminal, all supply circuits must be disconnected. 2-2. CAUTIONS RELATED TO NEW REFRIGERANT Cautions for units utilising refrigerant R410A Use new refrigerant pipes. Do not use refrigerant other than R410A. If other refrigerant (R22 etc.) is used, chlorine in refrigerant can cause deterioration of refrigerant oil etc.
Unit Gravimeter [3] Service tools Use the below service tools as exclusive tools for R410A refrigerant. No. 1 Tool name Specifications Gauge manifold · Only for R410A · Use the existing fitting specifications. (UNF1/2) · Use high-tension side pressure of 5.3MPa·G or over. 2 Charge hose 3 Electronic scale 4 Gas leak detector · Use the detector for R134a, R407C or R410A. 5 Adaptor for reverse flow check · Attach on vacuum pump.
Wired remote controller Display Section “Sensor” indication Day-of-Week Displayed when the remote controller sensor is used. Shows the current day of the week. For purposes of this explanation, all parts of the display are shown as lit. During actual operation, only the relevant items will be lit. Time/Timer Display “Locked” indicator Shows the current time, unless the simple or Auto Off timer is set. If the simple or Auto Off timer is set, the time to be switched off is shown.
Wireless remote controller CHECK TEST RUN display Indicate that the unit is being checked or test-run. MODEL SELECT display display Blinks when model is selected. Lights up while the signal is transmitted to the indoor unit when the button is pressed. Temperature setting display Indicates the desired temperature setting which is set. CLOCK display OPERATION MODE display Displays the current time. OPERATION MODE display Indicates which operation mode is in effect.
INDOOR UNIT INDOOR UNIT 4 SPECIFICATIONS Service Ref. Power supply(phase, cycle, voltage) Max. Fuse Size Min.Circuit Ampacity External finish Heat exchanger Fan Fan(drive) No. Fan motor output Fan motor Airflow(Low-Middle-High) External static pressure Operation control & Thermostat Noise level(Low-Middle-High) Field drain pipe O.D. Dimensions W D H Weight Service Ref. Power supply(phase, cycle, voltage) Max. Fuse Size Min.Circuit Ampacity External finish Heat exchanger Fan Fan(drive) No.
5 NOISE CRITERION CURVES PKA-A12HA PKA-A18HA PKA-A12HAL PKA-A18HAL NOTCH SPL(dB) 43 High 36 Low LINE 90 OCTAVE BAND SOUND PRESSURE LEVEL, dB (0dB=0.0002 μbar) 80 70 NC-70 60 NC-60 50 NC-50 40 NC-40 30 NC-30 20 APPROXIMATE THRESHOLD OF HEARING FOR CONTINUOUS NOISE NC-20 10 63 125 250 500 1000 2000 4000 8000 BAND CENTER FREQUENCIES, Hz UNIT WALL 3.3ft 3.
OUTLINES AND DIMENSIONS PKA-A12HA PKA-A12HAL PKA-A18HA PKA-A18HAL 15-3/16(387) Unit: inch (mm) 7-1/2(192) 7-3/4(197) Top side Mount board 23-9/16(599) Front side Right side 11-5/8(295) D Left side A 27-1/16(688) 2-1/8 (55) Knock out hole for left piping 9-13/16(249) 6-1/16(155) 35-3/8(898) 3/16(5) Knock out hole for right piping Front side(Grille open) Sleeve (purchased locally) :2-1/2~:3-1/8 (:65~:80) Through hole :2-1/2~:3-1/8 (:65~:80) Terminal block for indoor/outdoor connec
7 WIRING DIAGRAM PKA-A12HA PKA-A18HA PKA-A12HAL PKA-A18HAL [Explanation of symbols] Symbol I.B CN2L CN30 CN32 CN41 CN51 CN90 CN152 DSA FUSE LED1 LED2 LED3 SW1 SW2 SWE ZNR01,02 R.B TB6 Symbol Name M Indoor controller board MS Connector (LOSSNAY) S.W Connector (LLC) Connector ( Remote switch) SWE2 Connector (HA terminal-A) TB2 Connector (Centrally control) TB4 Connector (Remote operation adapter) TB5 Connector (Back-up heating) TH1 Surge absorber FUSE(T3.15AL250V) TH2 Power supply (I.B) Power supply (R.
8 REFRIGERANT SYSTEM DIAGRAM PKA-A12HA PKA-A18HA PKA-A12HAL PKA-A18HAL Strainer (#50) Heat exchanger Refrigerant GAS pipe connection (Flare) Thermistor TH2 Pipe temperature(Liquid) Thermistor TH5 (Cond./ Eva.
9 TROUBLESHOOTING 9-1. TROUBLESHOOTING Present and past error codes are logged and displayed on the wired remote controller or controller board of outdoor unit. Actions to be taken for service and the trouble reoccurrence at field are summarized in the table below. Check the contents below before investigating details.
9-2. MALFUNCTION-DIAGNOSIS METHOD BY REMOTE CONTROLLER When a malfunction occurs to air conditioner, both indoor unit and outdoor unit will stop and operation lamp blinks to inform unusual stop. [Procedure] 1. Press the CHECK button twice. • "CHECK" lights, and refrigerant address "00" blinks. • Check that the remote controller's display has stopped before continuing. 2. Press the temperature buttons.
• Refer to the following tables for details on the check codes. [Output pattern A] Beeper sounds OPERATION INDICATOR lamp blink pattern Beep Beep Beep Beep Off Beep 1st 2 nd 3 rd nth On On On On Beep Beep 1st Off On 2 nd · · · Repeated On 0.5 sec. Approx. 2.5 sec. 0.5 sec. 0.5 sec. Self-check Approx. 2.5 sec. 0.5 sec. 0.5 sec. 0.5 sec.
• On wireless remote controller The continuous buzzer sounds from receiving section of indoor unit. Blink of operation lamp • On wired remote controller Check code displayed in the LCD. (Refer to the previous page, check code.) • If the unit cannot be operated properly after the test run, refer to the following table to find out the cause.
9-3. SELF-DIAGNOSIS ACTION TABLE Error Code P1 Abnormal point and detection method Room temperature thermistor (TH1) The unit is in 3-minute resume prevention mode if short/open of thermistor is detected. Abnormal if the unit does not reset normally after 3 minutes. (The unit returns to normal operation, if it has been reset normally.) Constantly detected during cooling, drying, and heating operation.
Error Code P6 Abnormal point and detection method Countermeasure Cause Freezing/overheating protection is work- (Cooling or drying mode) (Cooling or drying mode) ing Check clogs of the filter. Clogged filter (reduced airflow) Freezing protection (Cooling mode) Remove shields. Short cycle of air path The unit is in 6-minute resume prevention Low load (low temperature) mode if pipe temperature stays under range Refer to 9-6.
Error Code Abnormal point and detection method Pipe temperature thermistor/ Condenser-Evaporator (TH5) The unit is in 3-minute resume protection mode if short/open of thermistor is detected. Abnormal if the unit does not get back to normal within 3 minutes. (The unit returns to normal operation, if it has been reset normally.
Error Code E3 or E5 E6 E7 Fb E1 or E2 Abnormal point and detection method Remote controller transmission error(E3)/signal receiving error(E5) Abnormal if remote controller could not find blank of transmission path for 6 seconds and could not transmit. (Error code: E3) Remote controller receives transmitted data at the same time, compares the data, and when detecting it, judges different data to be abnormal 30 continuous times.
9-4. TROUBLESHOOTING BY INFERIOR PHENOMENA Note: Refer to the manual of outdoor unit for the detail of remote controller. Phenomena (1)LED2 on indoor controller board is off. Cause • When LED1 on indoor controller board is also off. Power supply of rated voltage is not supplied to outdoor unit. Defective outdoor controller circuit board Power supply of 208/230V is not supplied to indoor unit.
Note: Refer to the manual of outdoor unit for the detail of remote controller. Phenomena (2)LED2 on indoor controller board is blinking. (3)Upward/downward vane performance failure Cause • When LED1 on indoor controller board is also blinking. Check indoor/outdoor unit connecting wire Connection failure of indoor/outdoor unit connecting for connection failure. wire • When LED1 is lit. Check the connection of remote controller wires in case of twin indoor unit Miswiring of remote controller wires system.
9-5. EMERGENCY OPERATION 9-5-1. When wireless remote controller fails or its battery is exhausted E.O. SW When the remote controller cannot be used When the batteries of the remote controller run out or the remote controller malfunctions, the emergency operation can be done using the emergency buttons. DEFROST/STAND BY lamp (ORANGE) Operation lamp (GREEN) Emergency operation switch (cooling/heating) Receiver • Each press of the emergency operation switch will toggle the operation mode.
9-6. HOW TO CHECK THE PARTS PKA-A12HA PKA-A18HA PKA-A12HAL Parts name PKA-A18HAL Check points Room temperature thermistor (TH1) Liquid pipe thermistor (TH2) Condenser/evaporator temperature thermistor (TH5) Disconnect the connector then measure the resistance using a tester. (At the ambient temperature 50 F~86 F) Vane motor (MV) Measure the resistance between the terminals using a tester. (Coil temperature 77 F) Red Normal 4.3k ~9.
9-6-2. DC Fan motor (fan motor/indoor controller circuit board) Check method of DC fan motor (fan motor/indoor controller circuit board) Notes · High voltage is applied to the connecter (CNMF) for the fan motor. Pay attention to the service. · Do not pull out the connector (CNMF) for the motor with the power supply on. (It causes trouble of the indoor controller circuit board and fan motor.) Self check Symptom : The indoor fan cannot rotate.
9-7. TEST POINT DIAGRAM Indoor controller board PKA-A12HA PKA-A12HAL PKA-A18HA PKA-A18HAL CNMF Connect to the fan motor (MF) 1-3 : DC294~325V 4-3 : DC15V 5-3 : DC0~6.5V 6-3 : DC0 or DC15V CN01 Connect to the Terminal block (TB4) 1-3 : 208/230VAC SWE Emergency operation connector FUSE (3.15A 250V) SW1 Model selection { LED1:Power supply (I.B) LED2:Power supply (R.
9-8. FUNCTIONS OF DIP SWITCH AND JUMPER WIRE Each function is controlled by the dip switch and the jumper wire on control P.C. board.
10 SPECIAL FUNCTION 10-1. Rotation Function (and back-up function, 2nd stage cut-in function) Only PKA-A·HA (Wired remote controller use model) 10-1-1. Operation (1) Rotation function (and Back-up function) Outline of functions · Main and sub units operate alternately according to the interval of rotation setting. w Main and sub unit should be set by refrigerant address.
System constraint · This function is available only in cooling mode. Ex.) Set temp. by R/C = 20:(68°F) Set point = 26:(79°F) When request code number is “323”. [2nd stage cut-in function]··· Request code number "322~324" Start operation 26: (79°F) 22: (71.5°F) 2nd unit Cut-in 4 degree C (7.5 degreeF) 2nd unit Cut-out Main unit IC-1 Sub unit IC-2 Room temp. Set point Sub unit start operation Run Stop Run 20: (68°F) 10-1-2.
(2) Setting method of each function by wired remote controller B: Refrigerant address C: Data display area D: Request code display area 1. Stop operation( ). 2. Press the TEST button ( ) for 3 seconds so that [Maintenance mode] appears on the screen ( ). After a while, [00] appears in the refrigerant address number display area.(at ) 3. Press the CHECK button ( ) for 3 seconds to switch to [Maintenance monitor].
11 DISASSEMBLY PROCEDURE PKA-A12HA PKA-A18HA PKA-A12HAL PKA-A18HAL OPERATION PROCEDURE Be careful when removing heavy parts. PHOTOS & ILLUSTRATIONS 1. REMOVING THE LOWER SIDE OF THE INDOOR UNIT FROM THE INSTALLATION PLATE Figure 1 (1) Remove the front panel. (2) Insert the screw driver to the corner hole at both left and right side as shown in the figure 1. (3) Push it up, then pull down the lower side of indoor unit and remove the hook.
OPERATION PROCEDURE PHOTOS 3. REMOVING THE INDOOR CONTROLLER BOARD AND WIRELESS CONTROLLER BOARD (1) Remove the front panel. (Refer to 2.) (2) Remove the room temp. thermistor TH1. (see Photo 3) (3) Remove the electrical box covers (screw 4 × 12). (See Photo 3) (4) Disconnect the connectors on the indoor controller board. (5) Remove the switch board cover. (6) Pull out the indoor controller board toward you, then disconnect the rest of connectors. Remove the indoor controller board and switch board.
OPERATION PROCEDURE PHOTOS 5. REMOVING THE NOZZLE ASSEMBLY (with VANE and VANE MOTOR) AND DRAIN HOSE Photo 8 (1) Remove the front panel (Refer to 2.). (2) Remove the electrical box cover. (3) Disconnect the vane motor connector (CN151) on the indoor controller board. (4) Remove the corner box. (5) Pull the nozzle assembly and detach. (6) Push the fixture and remove the drain hose.
OPERATION PROCEDURE PHOTOS 8. REMOVING THE LIQUID PIPE THERMISTOR AND COND/EVA TEMP. THERMISTOR (1) (2) (3) (4) (5) Remove the front panel. (Refer to 2) Remove the electrical box cover. Remove the motor band. Cut the wiring fixed band. Remove the liquid pipe thermistor and cond/eva temp. thermistor. (6) Disconnect the connector (CN44) on the indoor controller board. Condenser/evaporator temp. thermistor (TH5) Photo 13 Heat exchanger Liquid pipe thermistor (TH2) 9.
TM HEAD OFFICE : TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN CCopyright 2009 MITSUBISHI ELECTRIC ENGINEERING CO., LTD. Distributed in Mar. 2009 No.OCH456 PDF 7 Made in Japan New publication, effective Mar.
