SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS SPLIT-TYPE, AIR CONDITIONERS December 2010 No. OCH492 SERVICE MANUAL Indoor unit [Model names] [Service Ref.] Note: PCA-RP71HAQ • This manual describes only PCA-RP71HAQ service data of the indoor units. • RoHS compliant products have PCA-RP125HAQ PCA-RP125HAQ <G>...
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 R407C Do not use the existing refrigerant piping. Use liquid refrigerant to charge the system. The old refrigerant and lubricant in the existing piping If gas refrigerant is used to seal the system, the composition contains a large amount of chlorine which may cause the...
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[1] Cautions for service · After recovering the all refrigerant in the unit, proceed to working. · Do not release refrigerant in the air. · After completing the repair service, recharge the cycle with the specified amount of liquid refrigerant. [2] Refrigerant recharging (1) Refrigerant recharging process 1Direct charging from the cylinder.
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CAUTIONS RELATED TO NEW REFRIGERANT Cautions for units utilising refrigerant R410A Use new refrigerant pipes. Do not use refrigerant other than R410A. In case of using the existing pipes for R22, be careful with If other refrigerant (R22 etc.) is used, chlorine in refrige- the followings.
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Unit Gravimeter [3] Service tools Use the below service tools as exclusive tools for R410A refrigerant. 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. Charge hose ·...
PART NAMES AND FUNCTIONS Indoor (Main) Unit Left/right guide vanes Change the direction of airflow Air outlet from the horizontal blower. Oil filter (Air intake) It prevents oil from Up/down guide vanes getting into the unit. Change the direction of airflow from the Air intake vartical blower.
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Display “Sensor” indication Displays 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. During actual operation, only Time/Timer Display the relevant items will be lit. “Locked”...
WIRING DIAGRAM PCA-RP71HAQ PCA-RP125HAQ [LEGEND] Check code Symptom SYMBOL NAME SYMBOL NAME P. B INDOOR POWER BOARD MF1, MF2 FAN MOTOR Abnormality of room temperature thermistor TH1) I. B INDOOR CONTROLLER BOARD C1, C2 CAPACITOR (FAN MOTOR Abnormality of pipe temperature thermistor/Liquid TH2) FUSE FUSE (T6.3AL250V)
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.
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Note: Refer to the manual of outdoor unit for the details of display 9-2. SELF-DIAGNOSIS ACTION TABLE such as F, U, and other E. Abnormal point and detection method Countermeasure Error Code Cause Room temperature thermistor (TH1) 1 Defective thermistor 1–3 Check resistance value of thermistor.
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Abnormal point and detection method Countermeasure Error Code Cause Freezing/overheating protection is oper- (Cooling or drying mode) (Cooling or drying mode) ating 1 Clogged filter (reduced airflow) 1 Check clogs of the filter. 1 Freezing protection (Cooling mode) 2 Short cycle of air path 2 Remove blockage.
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Abnormal point and detection method Countermeasure Error Code Cause Pipe temperature thermistor / 1 Defective thermistor 1–3 Check resistance value of thermistor. Condenser-Evaporator (TH5) For characteristics, refer to (P1) above. characteristics 2 Check contact failure of connector (CN44) 1 The unit is in 3-minute resume protec- 2 Contact failure of connector on the indoor controller board.
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Abnormal point and detection method Countermeasure Error Code Cause Indoor/outdoor unit communication 1 Contact failure, short circuit or, * Check LED display on the outdoor control error (Signal receiving error) circuit board. (Connect A-control service miswiring (converse wiring) of 1 Abnormal if indoor controller board tool, PAC-SK52ST.) indoor/outdoor unit connecting cannot receive any signal normally for 6...
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9-3. TROUBLESHOOTING BY INFERIOR PHENOMENA Note: Refer to the manual of outdoor unit for the detail of remote controller. Phenomena Cause Countermeasure (1)LED2 on indoor controller board • When LED1 on indoor controller board is also off. 1 Check the voltage of outdoor power 1 Power supply of rated voltage is not supplied to out- supply terminal block (L, N) or (L3, N).
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Note: Refer to the manual of outdoor unit for the detail of remote controller. Phenomena Cause Countermeasure (2)LED2 on indoor controller board • 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.
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9-5. HOW TO CHECK THE PARTS PCA-RP71HAQ PCA-RP125HAQ Parts name Check points Room temperature Disconnect the connector then measure the resistance with a tester. thermistor (TH1) (At the ambient temperature 10 ~30 ) Pipe temperature thermistor (TH2) Normal Abnormal (Refer to <Thermistor Characteristic graph> for a detail.) Condenser/Evaporator 4.3k ~9.6k Open or short...
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9-6. TEST POINT DIAGRAM 9-6-1. Power board PCA-RP71HAQ PCA-RP125HAQ CN2S Connect to the indoor controller board (CN2D) Between 1 to 3 12.6-13.7V DC (Pin1 (+)) CNSK Connect to the indoor controller board (CNDK) Between 1 to 3 220-240V AC...
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9-6-2. Indoor controller board PCA-RP71HAQ PCA-RP125HAQ CN2D LED1 LED3 Connector to the indoor LED2 Power supply Transmission power board (CN2S) Power supply (I.B) (Indoor/outdoor) (12.5~13.7V DC) (R.B) CN3C Transmission – (Indoor/outdoor) (0~24V DC) CN22 Remote controller connecting wire – (10.4~14.6V DC) CN20 Room temperature thermistor (TH1)
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9-7. FUNCTIONS OF DIP SWITCH AND JUMPER WIRE Each function is controlled by the dip switch and the jumper wire on control P.C. board. SW1 and SW2 are equipped only for service parts. Model setting and capacity setting are memorized in the nonvolatile memory of the control P.C. board of the unit.
SPECIAL FUNCTION 10-1. ROTATION FUNCTION (AND BACK-UP FUNCTION, 2ND STAGE CUT-IN FUNCTION) 10-1-1. Operation (1) Rotation function (and Back-up function) • Outline of functions · Main and sub unit operate alternately according to the interval of rotation setting. w Main and sub unit should be set by refrigerant address. (Outdoor Dip switch setting) Refrigerant address "00"...
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10-1-2. How to set rotation function (Back-up function, 2nd stage cut-in function) You can set these functions by wired remote controller. (Maintenance monitor) NOTICE Both main and sub unit should be set in same setting. Every time replacing indoor controller board for servicing, the function should be set again. (1) Request Code List Rotation setting Setting No.
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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-RP71HAQ PCA-RP125HAQ OPERATING PROCEDURE PHOTOS & ILLUSTRATIONS 1. Removing the oil filter Figure 1 (1) Slide the oil filter towards you to remove. (See Figure 1) Oil filter Photo 1 2. Removing the terminal block box cover Filter rails Fan guard (1) Remove the oil filter.
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OPERATING PROCEDURE PHOTOS & ILLUSTRATIONS 4. Removing the fan motor Photo 4 (1) Remove the oil filter. (See Figure 1) (2) Remove the control box cover. (See Photo 2) Filter rail (3) Remove the room temperature thermistor connector (CN20) on the indoor controller board. (See Photo 3) (4) Remove a filter rail that is the nearest to the control box.
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OPERATING PROCEDURE PHOTOS 6. Removing the pipe temperature thermistor Photo 8 Relay connector (1) Remove the oil filter. (See Figure 1) (2) Remove the fan guard. (See Photo 1) (3) Remove the terminal block box cover. (4) Remove the white relay connector (2P) in the terminal block box.
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Heat exchanger (left) HEAD OFFICE : TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN New publication, effective Dec. 2010 CCopyright 2010 MITSUBISHI ELECTRIC ENGINEERING CO., LTD. Specifications subject to change without notice. Distributed in Dec. 2010 No.OCH492 Made in Japan...
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Related Links Model Number: PCA-RP125HAQ PCA-RP71-125HAQ Service Manual (OCH492) PCA-RP71-125HAQ Parts Catalog (OCH492) PCA-RP71-125HAQ Instruction Book (RG79D719H02) PCA-RP71-125HAQ Declaration of Conformity (CE2013A12) PCA-RP71-125HAQ Installation Manual (RG79D721H02)