SPLIT-TYPE, AIR CONDITIONERS November 2010 No. OCH484 SERVICE MANUAL Indoor unit [Model names] [Service Ref.] NOTE: PCA-A24KA4 • This manual describes only PCA-A24KA4 service data of the indoor units. PCA-A30KA4 • RoHS compliant products PCA-A30KA4 have <G> mark on the spec name plate.
REFERENCE MANUAL OUTDOOR UNIT’S SERVICE MANUAL Model name Service Ref. Service Manual No. PUZ-A18/24/30/36/42NHA4 PUZ-A18/24/30/36/42NHA4 PUZ-A18/24/30/36/42NHA4-BS PUZ-A18/24/30/36/42NHA4-BS OCH481 OCB481 PUY-A18/24/30/36/42NHA4 PUY-A18/24/30/36/42NHA4 PUY-A18/24/30/36/42NHA4-BS PUY-A18/24/30/36/42NHA4-BS Remote controller (Optional parts) Radio frequency interface Wired remote controller IR wireless remote controller COOL AUTO HEAT RF thermostat TEMP.
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 refrige- rant can cause deterioration of refrigerant oil etc.
[2] Additional refrigerant charge When charging directly from cylinder · Check that cylinder for R410A on the market is syphon type. · Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.) Unit Gravimeter [3] Service tools Use the below service tools as exclusive tools for R407C refrigerant.
Wired remote controller (Option) “Sensor” indication Display Section Displayed when the remote controller sensor is used. Day-of-Week For purposes of this explanation, Shows the current day of the week. all parts of the display are shown as lit. During actual operation, only Time/Timer Display the relevant items will be lit.
IR wireless remote controller (Option) 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.
SPECIFICATIONS PCA-A24KA4 Service Ref. Power supply(phase, cycle, voltage) 1 phase, 60Hz, 208/230V Max. Fuse Size Min.Circuit Ampacity External finish White Munsell 6.4Y 8.9/0.4 Heat exchanger Plate fin coil Fan(drive) Sirocco fan (direct) 0.095 Fan motor output Fan motor 0.54 F.L.A...
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Service Ref. PCA-A42KA4 Power supply(phase, cycle, voltage) 1 phase, 60Hz, 208/230V Max. Fuse Size Min.Circuit Ampacity External finish White Munsell 6.4Y 8.9/0.4 Heat exchanger Plate fin coil Fan(drive) Sirocco fan (direct) Fan motor output 0.160 F.L.A Fan motor 0.97 Dry: 23-25-27-29(810-885-955-1025) /min(CFM) Airflow(Low-Medium2-Medium1-High) Wet: 21-23-25-27(740-810-885-955)
NOISE CRITERION CURVES PCA-A24KA4 PCA-A30KA4 NOTCH SPL(dB) LINE NOTCH SPL(dB) LINE High High Medium1 Medium1 Medium2 Medium2 NC-70 NC-70 NC-60 NC-60 NC-50 NC-50 NC-40 NC-40 NC-30 NC-30 APPROXIMATE APPROXIMATE THRESHOLD OF THRESHOLD OF HEARING FOR HEARING FOR NC-20 NC-20 CONTINUOUS...
TROUBLESHOOTING 9-1. TROUBLESHOOTING <Error code display by self-diagnosis and actions to be taken for service (summary)> 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 <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> ■IR wireless remote controller [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 blink pattern Approx. 2.5 sec. 0.5 sec. 0.5 sec. 0.5 sec.
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• On IR 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. Symptom Cause Wired remote controller...
Note: Refer to the manual of outdoor unit for the details of display 9-3. SELF-DIAGNOSIS ACTION TABLE such as F, U, and other E. Abnormal point and detection method Countermeasure Error Code Cause Room temperature thermistor (TH1) Defective thermistor – Check resistance value of thermistor.
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Abnormal point and detection method Countermeasure Error Code Cause Freezing/overheating protection is (Cooling or drying mode) (Cooling or drying mode) opearting Clogged filter (reduced airflow) Check clogs of the filter. Freezing protection (Cooling mode) Short cycle of air path Remove blockage. The unit is in 6-minute resume prevention Low load (low temperature) mode if pipe <liquid or condenser/evapo-...
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Abnormal point and detection method Countermeasure Error Code Cause Pipe temperature thermistor/ Defective thermistor – Check resistance value of thermistor. Condenser-Evaporator (TH5) characteristics For characteristics, refer to (P1) above. The unit is in 3-minute resume protec- Check contact failure of connector (CN44) on Contact failure of connector the indoor controller board.
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Abnormal point and detection method Countermeasure Error Code Cause Remote controller transmission error(E3)/signal receiving error(E5) 2 remote controllers are set as Set a remote controller to main, and the “main.” Abnormal if remote controller could not other to sub. find blank of transmission path for 6 sec- (In case of 2 remote con- onds and could not transmit.
9-4. TROUBLESHOOTING BY INFERIOR PHENOMENA Note: Refer to the manual of outdoor unit for the detail of remote controller. Phenomena Cause Countermeasure (1)Upward/downward vane The vane is not downward during defrosting and heat Normal operation (The vane is set to performance failure preparation and when the thermostat is OFF in HEAT horizontal regardless of remote control.)
9-5. EMERGENCY OPERATION 9-5-1. When IR wireless remote controller fails or its battery is exhausted When the remote controller cannot be used When the batteries of the remote controller run out or the remote control- ler malfunctions, the emergency operation can be done using the emer- gency buttons on the grille.
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9-6. HOW TO CHECK THE PARTS PCA-A24KA4 PCA-A30KA4 PCA-A36KA4 PCA-A42KA4 Parts name Check points Room temperature Disconnect the connector then measure the resistance with a tester. thermistor (TH1) (At the ambient temperature 50 F~86 F) Liquid pipe thermistor (TH2) Normal...
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9-6-1. Thermistor <Thermistor Characteristic graph> <Thermistor for lower temperature> Room temperature thermistor (TH1) Thermistor for Pipe temperature thermistor/liquid (TH2) lower temperature Condenser/evaporator temperature thermistor (TH5) Thermistor R =15k ± 3% Fixed number of B=3480 ± 2% t( )Rt=15exp { 3480( 273+t T-32 273+...
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9-7. TEST POINT DIAGRAM Indoor controller board PCA-A24KA4 PCA-A30KA4 PCA-A36KA4 PCA-A42KA4 LED3 CN2L CN90 Transmission Connector (LOSSNAY) Connect to the IR wireless (Indoor/outdoor) remote controller board (CNB) Vane motor output (MV) CN4Y 12V pulse output i-see sensor (option) CN6Y Model selection...
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Setting by the dip switch and jumper wire Functions Remarks For service board Model settings Service board MODELS 1 2 3 4 5 PCA-A24KA4 1 2 3 4 5 PCA-A30KA4 Capacity settings 1 2 3 4 5 PCA-A36KA4 1 2 3 4 5 PCA-A42KA4 <Initial setting>...
SPECIAL FUNCTION 10-1. Rotation Function (and back-up function, 2nd stage cut-in function) This function is only available when using wired remote controller. 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.
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System constraint · This function is available only in cooling mode. Ex.) Set temp. by R/C = 20:(68°F) [2nd stage cut-in function]··· Request code number "322~324" Set point = 26:(79°F) When request code number is “323”. Room temp. Set point Room temp.
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(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 button ( ) for 3 seconds so that [Maintenance mode] appears on the screen ( ). TEST After a while, [00] appears in the refrigerant address number display area.(at 3.
DISASSEMBLY PROCEDURE PCA-A24KA4 PCA-A30KA4 Be careful when removing heavy parts. PCA-A36KA4 PCA-A42KA4 (Photo: PCA-A36KA4) OPERATING PROCEDURE PHOTOS & ILLUSTRATIONS Figure 1 1. Removing the air intake grille (1) Slide the air intake grille holding knobs (at 2 or 3 loca- tions) to the rear to open the air intake grille.
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OPERATING PROCEDURE PHOTOS & ILLUSTRATIONS 3. Removing the room temperature thermistor (TH1) Photo 4 (1) Remove the air intake grille. (See Figure 1,2) Casing (2) Remove the beam by removing 1 screw (4 8 PT) (See × Photo 1) (3) Remove 2 screws from the electrical cover, and remove the electrical cover.
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OPERATING PROCEDURE PHOTOS & ILLUSTRATIONS 5. Removing the fan (3 connection) Photo 9 (1) Remove the air intake grille. (See Figure 1,2) (2) Remove the beam by removing 1 screw (4 8 PT) (See × Photo 1) (3) Remove 2 screws from the electrical cover, and remove the electrical cover.
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OPERATING PROCEDURE PHOTOS & ILLUSTRATIONS Photo 12 7. Removing the vane motor (1) Remove the air intake. (See Figure 1,2) Connector (2) Remove the right side panel. (See Figure 3) Vane motor and cover (3) Remove the connector of vane motor. (4) Remove 2 screws of vane motor cover, then remove vane motor.
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OPERATING PROCEDURE PHOTOS & ILLUSTRATIONS Photo 17 10. Removing the thermistors/Liquid pipe (TH2) and con- denser/evaporator (TH5) (1) Remove the air intake grille. (See Figure 1, 2) (2) Remove the left and right side panels. (See Figure 3) (3) Remove the under panel. (See Photo 14) (4) Remove the drain pan.
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Heat exchanger Vane HEAD OFFICE : TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN New publication, effective Nov. 2010 CCopyright 2010 MITSUBISHI ELECTRIC ENGINEERING CO., LTD. Specifications subject to change without notice Distributed in Nov. 2010 No.OCH484 Made in Japan...
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