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SERVICE MANUAL & TEST RUN SERVICE MANUAL Mini VRF SYSTEM Model No. Outdoor Units HP = horsepower Rated Capacity Type Outdoor Unit Type 4 HP 5 HP 6 HP U-4LE2E5 U-5LE2E5 U-6LE2E5 LE2 mini VRF System U-4LE2E8 U-5LE2E8 U-6LE2E8 SM830258-01 REFERENCE NO.
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Model No. • To be connecting Indoor Unit Indoor Units Rated Capacity Type Indoor Unit Type D1 1-Way Cassette S-28MD1E5 S-36MD1E5 S-45MD1E5 S-56MD1E5 L1 2-Way Cassette S-22ML1E5 S-28ML1E5 S-36ML1E5 S-45ML1E5 S-56ML1E5 U2 4-Way Cassette S-22MU2E5A S-28MU2E5A S-36MU2E5A S-45MU2E5A S-56MU2E5A S-60MU2E5A Y2 4-Way Cassette 60 ×...
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• Connect all wiring tightly. Loose wiring circuit power Ssc greater than or equal to the values in may cause overheating at connection the table. points and a possible fire hazard. U-4LE2E5 U-5LE2E5 U-6LE2E5 • Provide a power outlet to be used 3,000 kVA...
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• When operating in emergency backup …In an Area with High Winds mode and switching from grid power to Securely anchor the outdoor unit down off-grid generator power or vice versa to with bolts and a metal frame. Provide a provide power for the air conditioner, be suitable air baffle.
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• Do not leak refrigerant while piping work Others for an installation or re-installation, and When disposal of the product, comply while repairing refrigeration parts. with national regulations. Handle liquid refrigerant carefully as it may cause frostbite. WARNING CAUTION When Servicing •...
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Check of Density Limit (3) If an indoor unit is installed in each partitioned room and the refrigerant tubing is interconnected, the smallest room Check the amount of refrigerant in the system and of course becomes the object. But when mechanical floor space of the room according to the legislation on ventilation is installed interlocked with a gas leakage refrigerant drainage.
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Precautions for Installation Using New Refrigerant 1. Care regarding tubing 1-1. Process tubing ● Material: Use seamless phosphorous deoxidized copper tube for refrigeration. Wall thickness shall comply with the applicable legislation. The minimal wall thickness must be in accordance with the table below. ●...
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Important Information Regarding The Refrigerant Used This product contains fluorinated greenhouse gases. Do not vent gases into the atmosphere. Refrigerant type: R410A value: 2088 GWP = global warming potential Periodical inspections for refrigerant leaks may be required depending on European or local legislation. Please contact your local dealer for more information.
Mini VRF SYSTEM 1. Introduction Control Functions - Outdoor unit Mini VRF SYSTEM is a multi system that is connected to a single outdoor unit. The outdoor unit contains an inverter compressor. To operate this system, the below settings must be made at the time of the test run. Table 1-1 At shipment Setting item...
Mini VRF SYSTEM 2. Compressor Control Control Functions - Outdoor unit (1) Compressors Mounted in the Outdoor Units Type of outdoor unit Inverter compressor ● ● ● Compressor (High pressure rotary) * The inverter compressor is operated according to the load and does not operate beyond outdoor unit capacity. (2) Operating Frequency Range of Inverter Compressor The inverter compressor can operate within the range in the table below.
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2WAY VRF SYSTEM Mini VRF SYSTEM 2. Compressor Control 3. Compressor Control Control Functions - Outdoor unit Control Functions (3) Forced Stopping of Compressor Once a compressor stops, it will not start for a period of 3 minutes (3-minute forced OFF). However, this is not applied when the compressor was forced to stop as the result of a special control operation.
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2WAY VRF SYSTEM Mini VRF SYSTEM 2. Compressor Control 3. Compressor Control Control Functions Control Functions - Outdoor unit 4-1. Evaporation temperature (= Te) control The cooling capacity is adjusted with this control. It prevents freezing of the indoor unit heat exchanger and the dew to the outside panel of the indoor unit.
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2WAY VRF SYSTEM Mini VRF SYSTEM 2. Compressor Control 3. Compressor Control Control Functions Control Functions - Outdoor unit ・Standard setting (at the shipment) °C °C Thermostat Thermostat Area D Area D PX=58.0 PX=58.0 57.9 57.9 Horsepower Horsepower Area C Area C decrease decrease...
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2WAY VRF SYSTEM Mini VRF SYSTEM 2. Compressor Control 3. Compressor Control Control Functions Control Functions - Outdoor unit When the temperature falls in the Area D (over PX temperature), the operation stops within 0 to 30 seconds at the interval of the roadmap control. After Tc falls in the Area D and the thermostat is turned OFF, the system may resume operating from the lower compressor capacity.
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The current limitation value changes to “normal status” and “overload status” according to the outdoor temperature. The primary and secondary current values of the inverter compressors are measured. U-4LE2E5, U-5LE2E5, U-6LE2E5 unit: Ampere Type of outdoor unit Limit current 1 32.2...
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Mini VRF SYSTEM 2. Compressor Control Control Functions - Outdoor unit U-4LE2E8, U-5LE2E8, U-6LE2E8 unit: Ampere Type of outdoor unit Limit current 1 14.0 14.0 14.0 Primary Maximum current 1 H 10.0 12.0 Maximum current 1 L 11.0 * Normally, maximum current is limited in demand control shown on page 1-26. Type of outdoor unit Limit current 2 15.2...
2WAY VRF SYSTEM Mini VRF SYSTEM 3. Output of PCB 4. Special Control Control Functions Control Functions - Outdoor unit Items Remarks Indication on PCB 4-way valve Solenoid valve Oil recovery valve ORVR valve MOV for heat exchanger MOV1 Motor Operated Valve MOV for Sub cooler MOV4 Crankcase heater...
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2WAY VRF SYSTEM Mini VRF SYSTEM 3. Output of PCB 4. Special Control Control Functions Control Functions - Outdoor unit (3) O Valve [O valve is the local supply parts. This valve works when the outdoor unit receives signal of the refrigerant leakage from the indoor unit. The indoor unit that transmits the signal of the refrigerant leakage gives “P14”alarm.
2WAY VRF SYSTEM Mini VRF SYSTEM 4. Outdoor Unit Fan Control 5. Outdoor Unit Fan Control Control Functions Control Functions - Outdoor unit (1) Number of Fan Motor Type of outdoor unit 4, 5, 6 HP Number of fan motor (2) Fan Step These outdoor units utilize a DC fan motor that can be controlled in 0∼15 steps (0∼15 modes) in ordinary mode.
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2WAY VRF SYSTEM Mini VRF SYSTEM 4. Outdoor Unit Fan Control 5. Outdoor Unit Fan Control Control Functions Control Functions - Outdoor unit (4) Fixed Initial Fan Step For the first 30 seconds after operation starts, the mode is fixed at the initial mode which was calculated from the relationship between the outdoor air temperature and the outdoor unit horsepower.
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2WAY VRF SYSTEM Mini VRF SYSTEM 4. Outdoor Unit Fan Control 5. Outdoor Unit Fan Control Control Functions Control Functions - Outdoor unit The system entirely becomes to the silent mode by setting in the main outdoor unit. EEPROM setting in main outdoor unit CODE : 05 Setting No.
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Mini VRF SYSTEM 4. Outdoor Unit Fan Control Control Functions - Outdoor unit (7) High Static Pressure Mode The outdoor unit allows a high static pressure changing the settings. The maximum permissible static pressure is 35Pa. EEPROM setting in each outdoor unit CODE:8F Setting No.
5. Outdoor Unit CCU (command controller 2WAY VRF SYSTEM Mini VRF SYSTEM 6. Outdoor Unit CCU (command controller unit) Control unit) Control Control Functions - Outdoor unit Control Functions Some actuators of indoor unit are controlled by CCU. MOV of Indoor Unit 1-1.
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5. Outdoor Unit CCU (command controller 2WAY VRF SYSTEM Mini VRF SYSTEM 6. Outdoor Unit CCU (command controller unit) Control Control Functions unit) Control Control Functions - Outdoor unit unit : pulse 1-2. Indoor unit with RAP valve kit Operating Operating Operating Thermostat...
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2WAY VRF SYSTEM 5. Outdoor Unit CCU (command controller Mini VRF SYSTEM 6. Outdoor Unit CCU (command controller unit) Control Control Functions unit) Control Control Functions - Outdoor unit (2) RAP Valve Kit Operating Operating Operating Thermostat RAP valve kit mode of mode of mode of...
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2WAY VRF SYSTEM 5. Outdoor Unit CCU (command controller Mini VRF SYSTEM 6. Outdoor Unit CCU (command controller unit) Control Control Functions unit) Control Control Functions - Outdoor unit 3-2. Heating mode The indoor unit fan in heating mode is stopped from the CCU in the following condition. Discharge air temperature of indoor unit ≤...
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5. Outdoor Unit CCU (command controller 2WAY VRF SYSTEM Mini VRF SYSTEM 6. Outdoor Unit CCU (command controller unit) Control Control Functions unit) Control Control Functions - Outdoor unit * Operating time “XX” under the section “(4) Drain Pump Control” described on previous page is able to set in EEPROM of the main outdoor unit.
2WAY VRF SYSTEM Mini VRF SYSTEM 6. Oil Control 7. Oil Control Control Functions Control Functions - Outdoor unit (1) Self-separator Oil Recovery Control Oil is recovered from the oil separator to the compressor through the ORVR. System Oil Recovery Control All indoor units MOV are opened for recovering oil from indoor side to compressor.
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2WAY VRF SYSTEM Mini VRF SYSTEM 6. Oil Control 7. Oil Control Control Functions Control Functions - Outdoor unit Indoor Unit Self Oil Recovery Control This control is carried out regularly when the system is in cooling mode. During stopped, fan mode setting or thermostat OFF condition at the indoor unit, MOV of the indoor unit is opened regularly for 1 minute (at the interval of approximately 40 minutes).
2WAY VRF SYSTEM Mini VRF SYSTEM 7. 4-Way Valve Adjustment Control 8. 4-Way Valve Adjustment Control Control Functions Control Functions - Outdoor unit The purpose of this control is to change over the 4-way valve appropriately with big pressure difference. This control is performed at the following conditions.
2WAY VRF SYSTEM Mini VRF SYSTEM 8. Defrost Control 9. Defrost Control Control Functions Control Functions - Outdoor unit (1) Type of Defrost Control This system uses the reverse cycle defrost. (2) Forced Conditions Defrost does not begin again for 35 minutes of operation after defrost was once completed. If the outdoor unit is stopped while defrosting due to protection control or another reason, then defrost control will not start for a minimum of 10 minutes after restart occurs.
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2WAY VRF SYSTEM Mini VRF SYSTEM 8. Defrost Control 9. Defrost Control Control Functions Control Functions - Outdoor unit Heating Operation Set Time (Defrosting Operation Prohibiting Time) When the heating operation time at system has exceeded “XX” minutes (35 minutes at initial setting), and at least one unit satisfies the decision of defrosting, the defrosting operation is effective.
Usual Demand Control Demand control is performed to suppress the horsepower not to make the primary current exceed the setting value. U-4LE2E5, U-5LE2E5, U-6LE2E5 The standard value of the limit current is shown in the table below. Type of outdoor unit unit:Amp.
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2WAY VRF SYSTEM Mini VRF SYSTEM 9. Demand Control 10. Demand Control Control Functions Control Functions - Outdoor unit Energy Saving Button (CZ-RTC5A / CZ-RTC5B) When the Energy Saving button of the indoor unit remote controller is pressed, demand control is performed according to EEPROM : 1A values.
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Mini VRF SYSTEM 2WAY SYSTEM 9. Demand Control 10. Upper Current Limitation Mode Control Functions - Outdoor unit Control Functions-Outdoor Unit NOTE Since the pattern “A” and “B” perform the outdoor unit current demand control (compressor’s suppressive drive), it is easy to grasp energy saving amount. However, it may cause the reduction of capacity in all indoor units of the same refrigerant system.
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2WAY SYSTEM 2WAY SYSTEM Mini VRF SYSTEM 10. Upper Current Limitation Mode 9. Demand Control 10. Demand Control Control Functions-Outdoor Unit Control Functions Control Functions - Outdoor unit (4) When Using Demand Terminal Block Demand terminal block must be connected in order to perform the demand control. (It is also possible to connect the optional Seri-Para I/O unit (optional CZ-CAPDC2) and setup the system.) The current limitation values can be set by changing either contact.
2WAY VRF SYSTEM Mini VRF SYSTEM 12. Other Functions 10. Other Functions Control Functions Control Functions - Outdoor unit (1) Auto Change over Cooling/Heating Function It is possible to select auto charge over cooling/heating mode in each remote controller even in mini VRF system. The system changes to cooling or heating operation according to number of thermostat ON mode.
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3WAY SYSTEM Mini VRF SYSTEM 13. Other Functions 10. Other Functions Control Functions Control Functions - Outdoor unit (2) Maintenance Function for Power Supply Stop of Indoor Unit (E06 ignore) The system can continue operation even if outdoor unit cannot communicate with some indoor units. It is necessary to set to EEPROM the allowed number of operating indoor units not to be able to communicate.
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Mini VRF SYSTEM 10. Other Functions Control Functions - Outdoor unit (3) Setting when at Thermostat OFF in Cooling Mode When decreasing the indoor airflow volume at the cooling thermostat OFF or dry thermostat OFF, follow the setting procedure below. EEPROM setting in main outdoor unit CODE: ED Indoor unit Setting No. Indoor fan mode Louver expansion valve 0 (factory preset mode) w/o force w/o force...
Mini VRF SYSTEM 11. Detailed Settings in EEPROM of Outdoor Control Functions - Outdoor unit Unit Never use the DN code unlisted in the following table. (P) : Factory preset mode Item Setting No. 0=Invalid (P) 1=Silent mode 1 Outdoor fan silent mode 2=Silent mode 2,,,,, 16=Silent mode 16 (For details, see "4.
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Mini VRF SYSTEM 11. Detailed Settings in EEPROM of Outdoor Control Functions - Outdoor unit Unit Never use the DN code unlisted in the following table. (P) : Factory preset mode Item Setting No. Outdoor unit capacity (Setting when the data is not stored in the EEPROM. 0=Invalid 15=112 17=140...
Mini VRF SYSTEM 12. Outdoor Unit Control PCB Control Functions - Outdoor unit (1) Outdoor Unit Control PCB U-4LE2E5, U-5LE2E5, U-6LE2E5 U-4LE2E5, U-5LE2E5, U-6LE2E5 CN-HPS NO. of I/U CN-LPS CN-TO JP001 CN-EXG CN-SCG CN-DISCH CN-SCT CN-EXL LED1 LED2 CN-ROM CN-EMG A.ADD...
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Mini VRF SYSTEM 12. Outdoor Unit Control PCB Control Functions - Outdoor unit U-4LE2E8, U-5LE2E8, U-6LE2E8 U-4LE2E8,U-5LE2E8,U-6LE2E8 JP001 CN-DISCH CN-EXL CN-SCT CN-SCG A.ADD CN-TO CN-MOV4 CN-EXG CN-EMG MODE CN-OC LED1 LED2 CN-RC CN-SILENT CN-ROM CN-LPS CN-MOV1 STOP CN-TERMINAL TEST CN-HPS 1 - 36...
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Mini VRF SYSTEM 12. Outdoor Unit Control PCB Control Functions - Outdoor unit 1-2. Outdoor Unit HIC PCB (2) Outdoor Unit HIC PCB U-4LE2E5, U-5LE2E5, U-6LE2E5 1 - 37 TD831186-00_欧州向け Mini VRF TD.indb 16/06/22 8:32:48...
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Mini VRF SYSTEM 12. Outdoor Unit Control PCB Control Functions - Outdoor unit U-4LE2E8,U-5LE2E8,U-6LE2E8 U-4LE2E8, U-5LE2E8, U-6LE2E8 1 - 38...
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Mini VRF SYSTEM 12. Outdoor Unit Control PCB Control Functions - Outdoor unit (3) Functions A. ADD pin (2P, Black) • Short circuited for over 1 second long → Auto address setting starts with open-circuit. • If short circuit lasts for over 1 second long during auto address setting, the setting is interrupted. Switches for setting system address 10s digit and 20s digit DIP switch (2P, Black) • If 10 systems or more are set, the setting is made by a combination of this DIP switch and...
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Mini VRF SYSTEM 12. Outdoor Unit Control PCB Control Functions - Outdoor unit CN-TERMINAL pin For communications circuit impedance matching (3P, Black) • A connecting socket (3P, Black) is attached to the terminal plug at the time of shipment from the factory.
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Mini VRF SYSTEM 12. Outdoor Unit Control PCB Control Functions - Outdoor unit Table 1-3 The number of indoor units settings (SW3, SW4) Indoor unit setting (SW3) Indoor unit setting (SW4) Number of indoor units (1P DIP switch) (Rotary switch) 1 - 9 unit Set to 1 - 9 (factory setting : 1 unit)
Mini VRF SYSTEM 1. Room Temperature Control Control Functions - Indoor Unit 1. Room Temperature Control The body sensor or remote controller sensor detects temperature in the room. The detected temperature is called the room temperature. The body sensor is the one contained in the indoor unit. Body sensor is enabled Remote controller sensor is enabled Set temp.
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Mini VRF SYSTEM 1. Room Temperature Control Control Functions - Indoor Unit Remote controller sensor is enabled Remote controller sensor is enabled Set temp. in remote Set temp. in remote 28℃ 28℃ 28℃ 20℃ 20℃ 20℃ controller controller Detected temp. by Detected temp.
Mini VRF SYSTEM 3. Automatic Fan Speed Control Control Functions - Indoor Unit 3. Automatic Fan Speed Control ① The indoor fan mode is controlled as shown below during the automatic fan mode. ② The fan mode does not change for 3 minutes during cooling operation and 1 minute during heating operation once it is changed.
4. Indoor Unit MOV Control Mini VRF SYSTEM Control Functions - Indoor Unit 5. Drain Pump Control 4. Indoor Unit MOV Control For details, see the Section 1. The MOV is at 480 pulses in the following cases. ① At the time of factory shipment ②...
Mini VRF SYSTEM 6. Automatic Heating / Cooling Control Control Functions - Indoor Unit 6. Automatic Heating / Cooling Control This function is only valid as long as one indoor unit is installed within one refrigerant system or all indoor units are controlled within a group control.
7. Discharge Air Temperature Control Mini VRF SYSTEM Control Functions - Indoor Unit 8. RAP Valve Kit Control 7. Discharge Air Temperature Control Discharge air temperature is controlled using the indoor unit discharge air temperature sensor. The discharge air temperature is set in the EEPROM on the PCB. The setting is different depending on the model. Discharge air temperature setting (at the time of factory shipment) Discharge air temperature setting Indoor unit type...
9. Automatic Flap Control Mini VRF SYSTEM Control Functions - Indoor Unit 10. Filter Sign 9. Automatic Flap Control The flap position can be selected from 5 positions. Operating mode Flap position Cooling / Dry F1・F2・F3 F1・F2・F3・F4・F5 Heating F1・F2・F3・F4・F5 ① The flap moves to the following position automatically when the indoor unit is stopped. F0 (close): Types K1, K2, T2, D1, U2, Y2 F5: Models other than the above ②...
Mini VRF SYSTEM 11. Fan Control during Dry Mode Control Functions - Indoor Unit 11. Fan Control during Dry Mode The fan control during dry mode is as follows. T (deg) Set temp. in remote controller Fan mode A: Fan mode set in the remote controller B: Fan mode is L during thermostat ON, LL during thermostat OFF For details on T, see “1.
12. Ventilation Fan Output Mini VRF SYSTEM Control Functions - Indoor Unit 13. T10 Terminal 12. Ventilation Fan Output The output of ventilation turns ON when the indoor unit turns ON. Also, when the indoor unit turns OFF, the output of the ventilation turns OFF. The ventilation fan can also be turned ON and OFF using the ventilation button on the remote controller.
Mini VRF SYSTEM 14. Parameter Control Functions - Indoor Unit 14. Parameter Indoor item code “06” Indoor item code “1E” Temperature shift for Heating intake cooling / heating change in Type Model temperature shift auto heat / cool mode Setting at time of factory Setting at time of factory shipment shipment...
Mini VRF SYSTEM 1. Removing Panels Outdoor Unit Repair Procedures Be sure to turn off the power before maintenance. When the power is turned off, CAUTION wait for 5 minutes without any work. Then start working. (1) Front panel removal •...
Mini VRF SYSTEM 2. Discharging Compressor Oil Outdoor Unit Repair Procedures 2-1. Discharging Oil in Compressor Recover the refrigerant in the outdoor unit following the procedures in “3. Recovering Refrigerant.” Remove the compressor and discharge the oil in it. See the section “8. Compressor” for detailed procedures. 2-2.
Mini VRF SYSTEM 3. Recovering Refrigerant Outdoor Unit Repair Procedures The following equipment and tools are required: Jumper wire with clips, adjustable wrench, set of manifold gauge valves specially designed for refrigerant R410A only, vacuum pump, refrigerant recovery unit, pre-purged refrigerant cylinder for recovery, flathead screwdriver, and outdoor unit maintenance remote controller.
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Mini VRF SYSTEM 3. Recovering Refrigerant Outdoor Unit Repair Procedures 3-2. Refrigerant Recovery Procedures (Indoor Unit) The flowchart below shows the refrigerant recovery procedures you must follow when replacing or repairing the indoor unit due to trouble in the refrigerant circuit. START 3-2-1.
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Mini VRF SYSTEM 3. Recovering Refrigerant Outdoor Unit Repair Procedures (2) If the remote controller is not available for maintenance of the outdoor unit 1 Short-circuit the MODE pin ("COOL" side) on the outdoor unit control PCB. 2 Short-circuit the CHK pin on the PCB to start test run operation. 3-2-2.
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Mini VRF SYSTEM 3. Recovering Refrigerant Outdoor Unit Repair Procedures 3-2-3. Refrigerant recovery procedures (2): Indoor unit with no ball valve equipped Refrigerant in all indoor units and the refrigerant tubing circuit can be pumped into the outdoor unit. The maximum refrigerant storage capacity per a single outdoor unit is approx.
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Mini VRF SYSTEM 3. Recovering Refrigerant Outdoor Unit Repair Procedures Manifold gauge Refrigerant Low-pressure outlet port recovery unit (for ø7.94mm-dia connector) High-pressure outlet port Refrigerant recovery cylinder (for ø7.94mm-dia connector) Gas tube service port (for ø7.94mm-dia connector) Liquid tube service port (for ø7.94mm-dia connector) Fig.
Mini VRF SYSTEM 4. Checking for Leakage After Repair Outdoor Unit Repair Procedures 4-1. Pressure Check for Leakage of Outdoor Unit After completing repair of the outdoor unit, carry out the following leakage check. (1) Check that all service valves for gas tube and liquid tube in the repaired outdoor unit (units necessary to carry out the pressurized leak check) are fully closed.
Mini VRF SYSTEM 5. Evacuating System Outdoor Unit Repair Procedures This procedure is carried out to ensure there is no remaining refrigerant or other gases (nitrogen, etc.) in the repaired outdoor unit and tubing. 5-1. Evacuating Repaired Outdoor Unit (1) Check that each service valve of the gas tube and liquid tube in the outdoor unit are fully closed. (2) Connect the manifold gauge valves to the high-pressure and low-pressure sensor outlets of the outdoor unit.
Mini VRF SYSTEM 6. Charging Compressor Oil Outdoor Unit Repair Procedures 6-1. If Refrigerant Has Already Been Charged to Outdoor Unit Be sure to use an exclusive oil-charging tank for charging compressor oil. Prior to charging, carry out vacuum drying inside the tank and take care that no air (in the form of bubbles) is permitted to enter the tank.
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Mini VRF SYSTEM 6. Charging Compressor Oil Outdoor Unit Repair Procedures Close Open Upper valve Manifold gauge Close Open Lower valve Vacuum pump When the predetermined amount of oil has been charged into the oil-charging tank, immediately close the lower valve.
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Mini VRF SYSTEM 2WAY SYSTEM 6. Charging Compressor Oil 7. Charging Compressor Oil Outdoor Unit Repair Procedures Outdoor Unit Repair Procedures Next, follow the instructions in “3-2-1. Cooling operation (for all units)” at the outdoor unit where oil will be charged, and start cooling operation at all units.
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2WAY SYSTEM Mini VRF SYSTEM 6. Charging Compressor Oil 7. Charging Compressor Oil Outdoor Unit Repair Procedures Outdoor Unit Repair Procedures 6-2. If Outdoor Unit Has Not Been Charged with Refrigerant When a compressor has been replaced or in any other case where the outdoor unit has not been charged with refrigerant, first charge with refrigerant then follow the instructions in “6-1.
Mini VRF SYSTEM 7. Pumping Out Refrigerant from Outdoor Unit Outdoor Unit Repair Procedures For the method used for additional oil charging after compressor replacement, see the section “6-1. If Refrigerant Has Already Been Charged to Outdoor Unit.” Required equipment and tools: Jumper wire with clips, adjustable wrench, set of manifold gauge valves for the refrigerant R410A, refrigerant recovery unit, pre-purged refrigerant cylinder for recovery, flathead screwdriver, and outdoor unit maintenance remote controller.
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Mini VRF SYSTEM 7. Pumping Out Refrigerant from Outdoor Unit Outdoor Unit Repair Procedures (7) Short-circuit the AP pin on the outdoor unit control PCB. Then turn ON the outdoor unit power. When the AP pin is short-circuited and the power is turned ON, all solenoid valves in the outdoor unit are forced open, allowing the refrigerant to be recovered from all CAUTION tubes which are separated by solenoid valves.
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Mini VRF SYSTEM 7. Pumping Out Refrigerant from Outdoor Unit Outdoor Unit Repair Procedures (4) Then slowly close the liquid tube service valve. * When the low pressure at the outdoor unit to be repaired reaches 0.5 MPa or below, pull out the SCT connec- tor from the outdoor unit control PCB of that outdoor unit.
Mini VRF SYSTEM 8. Compressor Outdoor Unit Repair Procedures 8-1. Compressor Trouble Diagnosis and Check Methods Generally, compressor failures can be classified into the following categories. (1) Mechanical trouble (A) Locking (intrusion of foreign objects, galling, etc.) (B) Pressure rise failure (damaged valve, seal, bearing, or other component) (C) Noise (damaged stator rotor, valve, or other component) (2) Electrical trouble (A) Coil burning...
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Mini VRF SYSTEM 8. Compressor Outdoor Unit Repair Procedures 8-2. Replacing the Compressor(s) 8-2-1. Replacing compressor (1) Follow the instructions in “8-3. Removing Compressor” and replace the failed compressor. (2) Fully close the high- and low-pressure gauge valves on the manifold gauge, then stop the vacuum pump. (3) Disconnect the manifold gauge from vacuum pump.
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Mini VRF SYSTEM 8. Compressor Outdoor Unit Repair Procedures 8-2-2. Dry core cleaning If burning or other failures occur repeatedly at compressors, in many cases the cause is acid, sludge, carbon, or other substances that remain in the refrigeration cycle as the result of insufficient cleaning. If, when the oil is inspected, there is an outdoor unit where the oil color phase is 4.0 or higher, or where a sharp odor is present, carry out all steps below to perform dry core cleaning.
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Mini VRF SYSTEM 8. Compressor Outdoor Unit Repair Procedures (16) After evacuating all nitrogen gas from the tubing, apply vacuum to outdoor unit where dry cores were removed until the pressure is –101kPa {–755 mm Hg, 5 Torr} or less. (17) Refer to the Installation Instructions for further information.
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2WAY SYSTEM Mini VRF SYSTEM 9. Compressor 8. Compressor Outdoor Unit Repair Procedures Outdoor Unit Repair Procedures 8-3. Removing Compressors Use caution to prevent water or foreign particles from invading the refrigerant tube while removing and installing the compressor. 8-3-1. Removing Compressors After recovering refrigerant in the system, replace the nitrogen gas through the service valve port.
Mini VRF SYSTEM 1. Overview Outdoor Unit Maintenance Remote Controller OUTDOOR UNIT MAINTENANCE REMOTE [Service Checker Section] CONTROLLER (CZ-RTC4) n About the outdoor unit maintenance remote controller The outdoor unit utilizes nonvolatile memory (EEPROM) on its PCB. This allows EEPROM data to replace the setting switches that were present on previous PCBs.
Mini VRF SYSTEM 2. Functions Outdoor Unit Maintenance Remote Controller n Functions on the ordinary display (1) Functions: Button operations can be used to perform the following functions. • Start/stop of all indoor units • Switching between cooling and heating •...
Mini VRF SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller n Functions on the ordinary display • Connect the special service checker wiring to the outdoor unit PCB. The connection is shown in the figure below. Outdoor unit PCB When connecting the special service (3P, BLU)
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Mini VRF SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller All units start/stop <Operation> (Start/Stop operation) button can be used to start and stop all the indoor units. • The LED illuminates if any indoor units is operating. •...
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Mini VRF SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller n Display (functions) • Use the temperature setting buttons to change the item code. À Item code Á Item Remarks Outdoor unit alarm Alarm code display No.
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Mini VRF SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller XX-YY R.C.  Locations where À Á , and  are displayed as Displays the outdoor unit sub-bus address which is shown in Fig. 1. currently selected. XX = Outdoor system address on main bus line (1 –...
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Mini VRF SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller n Concerning the 7-segment, 4-digit display remote controller timer display The unit Nos. of connected units are indicated by four 7-segment digits ( ) and a colon. Display of unit Nos.
Mini VRF SYSTEM 4. Monitoring Operations Outdoor Unit Maintenance Remote Controller Display the indoor unit and outdoor unit sensor temperatures. <Operating procedure> Press and hold the (Check) button and À buttons simultaneously for 4 seconds or longer to engage temperature monitor mode. During temperature monitoring, is illuminates.
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Mini VRF SYSTEM 4. Monitoring Operations Outdoor Unit Maintenance Remote Controller Display of unit No. 1 (main unit) Description Remarks Indoor unit intake temp. (TA) °C Indoor unit heat exchanger temp. E1 (E1) °C — Indoor unit Indoor unit heat exchanger temp. E3 (E3) °C Discharge air temp.
Mini VRF SYSTEM 5. Outdoor Unit Alarm History Monitor Outdoor Unit Maintenance Remote Controller • Displays outdoor unit alarms only. • Check the indoor unit alarm histories separately using the indoor unit remote controllers or other control device. <Operating procedure> À...
2WAY SYSTEM Mini VRF SYSTEM 6. Mode Settings 6. Mode Settings Outdoor Unit Maintenance Remote Controller Outdoor Unit Maintenance Remote Controller Display of fi rst 3 digits Setting mode 1 <Operating procedure> Press and hold the (Check) button and (Ventilation) button simultaneously for 4 seconds or longer.
Mini VRF SYSTEM 1. Simple Settings Function Remote Controller Functions • This allows the filter lifetime, operating mode priority change, central control address, and other settings to be made for an individual or group- 20:30 (THU) control indoor unit to which the remote controller used for simple settings is connected.
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Mini VRF SYSTEM 1. Simple Settings Function Remote Controller Functions <Procedure of CZ-RTC4> 1 Press and hold the buttons simultaneously for 4 seconds or longer. 2 “ ”, unit No. “ ” (or “ ” in the case ° of group control), item code “ ”, and settings °...
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Mini VRF SYSTEM 1. Simple Settings Function Remote Controller Functions List of Simple Setting Items Setting data Item code Item Description 0000 Not displayed 0001 150 hours 0002 2,500 hours Filter sign ON time (filter life time) 0003 5,000 hours 0004 10,000 hours 0005...
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Mini VRF SYSTEM 1. Simple Settings Function Remote Controller Functions Simple setting items Item code Item Description Filter sign ON time setting Changes the indoor unit filter lifetime when a high-performance filter or other (filter lifetime) optional product is installed. Reduces the filter sign ON time to 1/2 of the standard time (setting at the time of Degree of filter fouling shipping) for cases when filter fouling is more severe than normal.
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Mini VRF SYSTEM 1. Simple Settings Function Remote Controller Functions Item code Item Description Set when using a central control device. Central control address Used when setting the central control address manually from the remote controller. Operating mode priority change Note (1) NOTE (1) Explanation of operation mode priority change...
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Mini VRF SYSTEM 1. Simple Settings Function Remote Controller Functions When the operating mode at the priority remote controller is changed, the operating modes of other remote controllers change as shown below. Mode change at priority remote controller Operating modes at other remote controllers Current mode New mode Current mode...
Mini VRF SYSTEM 2. Detailed Settings Function Remote Controller Functions • This allows the system address, indoor unit address, and other settings to be made for the individual or group-control indoor unit to which the remote controller used for detailed settings is 20:30 (THU) connected.
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Mini VRF SYSTEM 2. Detailed Settings Function Remote Controller Functions <Procedure of CZ-RTC4> 1 Press and hold the buttons simultaneously for 4 seconds or longer. 2 “ ”, unit No. “ ”, item code “ ”, and ° settings data “ ”...
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2WAY SYSTEM Mini VRF SYSTEM 2. Detailed Settings Function 2. Detailed Settings Function Remote Controller Functions Remote Controller Functions List of Detailed Setting Items Setting data Item code Item Description Description Description 0001 4-Way Cassette (60×60) (U2, Y2) 0002 2-Way Cassette (L1) 0003 1-Way Cassette (D1) Low Silhouette Ducted (F2)
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Mini VRF SYSTEM 2. Detailed Settings Function Remote Controller Functions Setting data Item code Item Description 0000 5 minutes (1B) Forced thermostat ON time 0001 4 minutes –010 Shifts discharge temperature setting 10°C down –009 Shifts discharge temperature setting 9°C down Cooling discharge –008 Shifts discharge temperature setting 8°C down...
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Mini VRF SYSTEM 2. Detailed Settings Function Remote Controller Functions Setting data Item code Item Description 0000 No forced operation 0001 Forced operation for 1 minute Automatic drain pump operation 0060 Continuous operation 0000 None Ventilation fan operation 0001 Ventilation fan operated by remote controller. Wired remote controller 0000 Not used.
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Mini VRF SYSTEM VRF SYSTEMS Indoor Unit 2. Detailed Settings Function 2. Detailed Settings Function Remote Controller Functions Setting data Item code Item Description DC fan tap operating Purpose mode 0000 Standard Standard (setting at shipment) High ceiling use High ceiling setting 1 (with standard panel) 0001 For low Ultra long-life filter, oil guard panel, ammonia deodorizing...
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Mini VRF SYSTEM VRF SYSTEMS Indoor Unit 2. Detailed Settings Function 2. Detailed Settings Function Remote Controller Functions Setting data Item code Item Description 0000 Without nanoe™ X function With or without nanoe™ X function, 0001 With nanoe™ X function (Not operational if R/C with nanoe™ X not connected) Operation setting 0002 With nanoe™...
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Mini VRF SYSTEM 2. Detailed Settings Function Remote Controller Functions Item code Item Description Unit type Set when the indoor unit EEPROM memory is replaced during servicing. Indoor unit capacity System (outdoor unit) address These are not set at the time of shipping from the factory. Indoor unit address These must be set after installation if auto address setting is not performed.
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Mini VRF SYSTEM 2. Detailed Settings Function Remote Controller Functions Item code Item Description 1F (Upper limit) Cooling 20 (Lower limit) 21 (Upper limit) This setting changes the temperature range (upper limit and lower limit) Heating 22 (Lower limit) Change to the remote which is set from the remote controller or central control device.
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Mini VRF SYSTEM 2. Detailed Settings Function Remote Controller Functions (Continued from previous page) Item code Item Description Heat exchanger temperature for The heat exchanger temperature control point for prevention of cold air cold air discharge discharge during heating operation can be changed. The indoor unit PCB optional output for the fan can be switched Fan output switching according to the purpose of use.
Mini VRF SYSTEM 3. Remote Controller Servicing Functions Remote Controller Functions 2WAY SYSTEM 3. Remote Controller Servicing Functions Remote Controller Functions The remote controller includes a number of servicing functions. Use these as needed for test runs and inspections. <Function of CZ-RTC5A / CZ-RTC5B> Display of "maintenance function"...
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Mini VRF SYSTEM 3. Remote Controller Servicing Functions Remote Controller Functions <CZ-RTC4> List of Servicing Functions Functions Description Button operation Reset operation Unit status Operation with forced Press and hold the button for Test run 4 seconds or longer. thermostat ON Sensor Temperature display Press and hold the...
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Mini VRF SYSTEM VRF SYSTEMS Indoor Unit 3. Remote Controller Servicing Functions 3. Remote Controller Servicing Functions Remote Controller Functions ■ ECONAVI Display When the appears on the LCD display, the state of the sensor unit can be checked in the following method.
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Mini VRF SYSTEM VRF SYSTEMS Indoor Unit 3. Remote Controller Servicing Functions 3. Remote Controller Servicing Functions Remote Controller Functions Code no. Description ECONAVI sensor ECONAVI panel Data shows the status of the ECONAVI sensor. 0000: The sensor is not connected. 0001: The sensor can detect human motion.
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Mini VRF SYSTEM VRF SYSTEMS Indoor Unit 3. Remote Controller Servicing Functions 3. Remote Controller Servicing Functions Remote Controller Functions Check of ECONAVI Operational Status The status of ECONAVI operation can be checked instantly. It is available to check the operation when installing the indoor unit. <Procedure of CZ-RTC5A / CZ-RTC5B>...
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2WAY SYSTEM Mini VRF SYSTEM 3. Remote Controller Servicing Functions 3. Remote Controller Servicing Functions Remote Controller Functions Remote Controller Functions Test Run Function Operates the unit with the thermostat forced ON. <Procedure of CZ-RTC5A / CZ-RTC5B> 1 Keep pressing the 20:30 (THU) buttons simultaneously for 4 or more seconds.
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Mini VRF SYSTEM 3. Remote Controller Servicing Functions Remote Controller Functions <Procedure of CZ-RTC4> 1 Press and hold the button for 4 seconds or longer. 2 “ ” appears on the remote controller LCD ° ° display. 3 Press the button to start the test run.
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Mini VRF SYSTEM 3. Remote Controller Servicing Functions Remote Controller Functions n Sensor Temperature Display Function (displayed regardless of whether unit is operating or stopped) Sensor info. 20:30 (THU) Unit no. Code no. Data The procedure below displays the sensor 0026 temperatures from the remote controller, indoor unit, 0028...
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Mini VRF SYSTEM 3. Remote Controller Servicing Functions Remote Controller Functions <Procedure of CZ-RTC4> 1 Press and hold the buttons simultaneously for 4 seconds or longer. ” 2 The unit No. “X-X” (main unit No.), item code “ ° (sensor address), and servicing monitor “ ”...
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Mini VRF SYSTEM VRF SYSTEMS Indoor Unit 3. Remote Controller Servicing Functions 3. Remote Controller Servicing Functions Remote Controller Functions ■ nanoe™ X Display When the appears on the remote controller (CZ-RTC5A / CZ-RTC5B), the status of the nanoe™ X can be checked in the following way.
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Mini VRF SYSTEM VRF SYSTEMS Indoor Unit 3. Remote Controller Servicing Functions 3. Remote Controller Servicing Functions Remote Controller Functions In the case of the nanoe™ X module status other than "Normal" or "Unsupported" If the menu "13. nanoe" is not displayed or the module status becomes other than "Normal" or "Unsupported" even though the nanoe™...
1. Contents of Remote Controller 2WAY SYSTEM 1. Contents of Remote Controller Mini VRF SYSTEM Trouble Diagnosis Switch Alarm Display Trouble Diagnosis Switch Alarm Display Blinking: OFF: Wired Wireless remote remote controller control receiver display display Possible cause of malfunction Serial Remote controller is detecting Remote controller is not connected properly.
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1. Contents of Remote Controller 2WAY SYSTEM 1. Contents of Remote Controller Mini VRF SYSTEM Trouble Diagnosis Switch Alarm Display Trouble Diagnosis Switch Alarm Display Blinking: OFF: Wired Wireless remote remote controller control receiver display display Possible cause of malfunction Thermistor fault Outdoor thermistor is either Compressor inlet temperature sensor has failure.
Mini VRF SYSTEM 2. Outdoor Unit Control Panel LED Display Trouble Diagnosis : ON : Blinking : OFF) LED (RED) Display meaning After the power is turned ON (and auto address setting is not in progress), no communication with the indoor units in that system is possible. (Both ON) After power is turned ON (and auto address setting is not in progress), one or more indoor units are confirmed in that system;...
Mini VRF SYSTEM 3. Mini VRF Alarm Codes Trouble Diagnosis Alarm code Alarm meaning Page Some indoor units do not respond to outdoor unit. Auto Address failed to start. Fewer indoor units are found in Auto Addressing than the setting on outdoor PCB. More indoor units are found in Auto Addressing than the setting on outdoor PCB.
Mini VRF SYSTEM 3. Mini VRF Alarm Codes Trouble Diagnosis E06 Alarm Alarm code Alarm meaning Some indoor units do not respond to outdoor unit. Alarm conditions Outdoor unit failed to receive serial communication signals from indoor unit. Probable cause (1) The indoor unit power was cut OFF after initial communications were completed.
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(3) Check the power at the indoor units. Correction (1) Reconnect the inter-unit control wire from the outdoor unit to the indoor unit. Example — Notes Position of serial terminal base U-4LE2E5, U-5LE2E5, U-6LE2E5 U-4LE2E8, U-5LE2E8, U-6LE2E8 terminal base terminal base 6 - 7...
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Mini VRF SYSTEM 3. Mini VRF Alarm Codes Trouble Diagnosis F04 Alarm Alarm code Alarm meaning Compressor discharge temperature sensor has failure. (DISCH) Alarm conditions (1) Discharge temp. of 100°C or higher was detected 30 minutes or more after that compressor stopped operating.
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Mini VRF SYSTEM 3. Mini VRF Alarm Codes Trouble Diagnosis F06 Alarm Alarm code Alarm meaning Outdoor unit heat exchanger gas temperature sensor has failure. (EXG) Alarm conditions (1) Short circuit (A/D step is 10 steps or less) (2) Open circuit (A/D step is 1014 steps or more) Probable cause (1) Sensor malfunction (including connector) (2) The Outdoor Unit Control PCB malfunction...
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3WAY SYSTEM Mini VRF SYSTEM 3. Mini VRF Alarm Codes 4. 3WAY Alarm Codes Trouble Diagnosis Trouble Diagnosis F16 Alarm Alarm code Alarm meaning High pressure sensor has failure. (HPS) Alarm conditions High-pressure sensor disconnected or open circuit High-pressure sensor detected over 3.6MPa continuously for 30 minutes while outdoor units stopped. High-pressure sensor detected over 3.6MPa while outdoor units were operating.
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(1) Check the non-volatile memory on the Outdoor Unit Control PCB. Correction — Example — Notes — H01 Alarm (U-4LE2E5, U-5LE2E5, U-6LE2E5) Alarm code Alarm meaning Compressor primary current is overcurrent. Alarm conditions Compressor (INV) primary current detected overcurrent higher than 32.2 (A). Probable cause...
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(3) Replace the HIC PCB. Example — Notes — H03 Alarm (U-4LE2E5, U-5LE2E5, U-6LE2E5) Alarm code Alarm meaning Compressor current sensor is disconnected or shorted. Alarm conditions When the frequency of compressor (INV) is over 35Hz and the secondary current is over 5.0A, the primary current detected lower than 1.0A.
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Mini VRF SYSTEM 3WAY SYSTEM 3. Mini VRF Alarm Codes 4. 3WAY Alarm Codes Trouble Diagnosis Trouble Diagnosis H05 Alarm Alarm code Alarm meaning Compressor discharge temperature sensor is disconnected, shorted or misplaced. (DISCH) Alarm conditions • This alarm occurs when the discharge sensor temperature detector is not inserted into the tube’s sensor holder, or when the sensor itself has suffered some kind of malfunction other than a cut wire.
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Mini VRF SYSTEM 3. Mini VRF Alarm Codes Trouble Diagnosis H31 Alarm (U-4LE2E5, U-5LE2E5, U-6LE2E5) Alarm code Alarm meaning Compressor HIC has failure. HIC is overcurrent or overheat. VDC is undervoltage or overvoltage. Alarm conditions This alarm occurs when the microcomputer identifies a trouble signal (indicating abnormal HIC temperature or other trouble) from the HIC.
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Mini VRF SYSTEM 3. Mini VRF Alarm Codes Trouble Diagnosis H31 Alarm (U-4LE2E8, U-5LE2E8, U-6LE2E8) Alarm code Alarm meaning Compressor HIC has failure. HIC is overcurrent or overheat. VDC is undervoltage or overvoltage. Alarm conditions This alarm occurs when the microcomputer identifies a trouble signal (indicating abnormal HIC temperature or other trouble) from the HIC.
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Mini VRF SYSTEM 3. Mini VRF Alarm Codes Trouble Diagnosis L04 Alarm Alarm code Alarm meaning Duplicate system address setting on outdoor units. Alarm conditions Communication by inter-unit control wiring was received that contained the same address as that unit 5 times or more within 3 minutes. Probable cause Incorrect outdoor system address settings Check...
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2WAY SYSTEM Mini VRF SYSTEM 4. 2WAY Alarm Codes 3. Mini VRF Alarm Codes Trouble Diagnosis Trouble Diagnosis P03 Alarm Alarm code Alarm meaning Compressor discharge temperature is too high. Alarm conditions Compressor : Pre-trip stops when the temperature exceeds 106°C. * The alarm occurs when pre-trip stop occurs more than once.
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3WAY SYSTEM Mini VRF SYSTEM 4. 3WAY Alarm Codes 3. Mini VRF Alarm Codes Trouble Diagnosis Trouble Diagnosis P04 Alarm Alarm code Alarm meaning High pressure swich is activated. Alarm conditions The operation of the electronic circuit in the high-pressure switch may short-circuit the terminal depending on the pressure.
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Mini VRF SYSTEM 3. Mini VRF Alarm Codes Trouble Diagnosis P05 Alarm Alarm code Alarm meaning AC power supply has abnormal. Alarm conditions AC power supply trouble. Probable cause (1) Instantaneous blackout (2) Zero-cross (waveform input of power supply) error (3) DC voltage charge failure Check (1) Check the power supply and power wiring.
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Changed to output error by current regardless of the inverter frequency. When more than the current values shown in the table are instantly detected in the secondary current. Secondary current HIC PCB Model name U-4LE2E5 U-5LE2E5 U-6LE2E5 Current (A) 24.5 Inverter compressor Model name...
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Mini VRF SYSTEM Check Check the valve, mechanical valve and outdoor fan. 3. Mini VRF Alarm Codes Correction — Trouble Diagnosis Example — — Notes P22 Alarm Alarm code Alarm meaning Outdoor unit fan motor has failure. Alarm conditions Fan motor start failure, fan motor Hall IC input failure Probable cause (1) Wiring failure (2) Outdoor Unit Control PCB failure...
Mini VRF SYSTEM 4. Inspection and Characteristics of Parts Trouble Diagnosis (1) High-Pressure Switch (63PH) 63PH Disconnect the CN-63PH connector (3P, red) from the outdoor unit control panel. Measure the resistance between socket pins 1 and 3. The resistance is OK if the result is 0 Ω. (2) Electronic Control Valve (MOV1, MOV4) After removing the connector from the PCB, use the following methods to check the valves.
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Mini VRF SYSTEM 2WAY VRF SYSTEM 4. Inspection and Characteristics of Parts 8. Thermister Characteristics Curve Trouble Diagnosis Trouble Diagnosis (4) Indoor suction air (room) temp. sensor (TA) Indoor discharge air temp. sensor (BL) Temperature (˚C) (5) Indoor coil temp. sensor (E1, E3) Temperature (˚C) Temperature (˚C) 6 - 23...
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Mini VRF SYSTEM 6. Inspection and Characteristics of Parts 4. Inspection and Characteristics of Parts Trouble Diagnosis Trouble Diagnosis (6) Coil Resistance of Compressor Motor U-4LE2E5, U-5LE2E5, U-6LE2E5 U-4LE2E8, U-5LE2E8, U-6LE2E8 unit : ohm unit : ohm Compressor Compressor 5VD420XEB21...
When the test pin on the outdoor unit control PCB is short-circuited, each part can be operated individually. • After turning OFF the main unit power, short-circuit the test pin (black), then turn the power back ON. Output is performed in the sequence shown in the table below, for 0.5 seconds each. U-4LE2E5, U-5LE2E5, U-6LE2E5 Output Operation...
Mini VRF SYSTEM 6. Symptom: Thermostat in OFF continues or 6. Symptom: Thermostat in OFF continues or Mini VRF SYSTEM Trouble Diagnosis cycles OFF & ON too frequently Trouble Diagnosis cycles OFF & ON too frequently How to detect abnormality •...
Mini VRF SYSTEM Contents Test Run 7. TEST RUN 1. Preparing for Test Run ......................7-2 2. Test Run Procedure ......................7-3 3. Main Outdoor Unit P.C.Board Setting ................7-4 4. Auto Address Setting ......................7-9 5. Setting Test Run Remote Controller ................7-15 6.
Mini VRF SYSTEM 1. Preparing for Test Run Test Run 1. Preparing for Test Run (6) Both the gas and liquid tube service valves are open. If not, open them now. ● Before attempting to start the air conditioner, check the following.
Mini VRF SYSTEM 2. Test Run Procedure Test Run 2. Test Run Procedure Note: Recheck before the test run. These settings are not made on the indoor unit P.C. board. <Outdoor main unit control P.C. board> Number of indoor units Set the number of indoor units.
Mini VRF SYSTEM 3. Main Outdoor Unit P.C.Board Setting Test Run 3. Main Outdoor Unit P.C. Board Setting U-4LE2E5, U-5LE2E5, U-6LE2E5 SW 2 SW 1 SW 3 SW 4 STOP A. ADD MODE CN-SILENT LED 1 LED 2 CN-ROM CN-RC...
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Mini VRF SYSTEM 3. Main Outdoor Unit P.C.Board Setting Test Run U-4LE2E8, U-5LE2E8, U-6LE2E8 LED 2 LED 1 SW 2 SW 1 SW 4 SW 3 A. ADD STOP MODE CN-TERMINAL CN-SILENT CN-ROM CN-OC CN-EMG AP CN-RC For detailed drawing, see the page 7-7. 7 - 5...
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Mini VRF SYSTEM 3. Main Outdoor Unit P.C.Board Setting Test Run The number of indoor units settings (SW3, SW4) Indoor unit setting (SW3) Indoor unit setting (SW4) Number of indoor units (1P DIP switch) (Rotary switch) 1 - 9 unit Set to 1 - 9 (factory setting : 1 unit) 10 - 12 unit...
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Mini VRF SYSTEM 3. Main Outdoor Unit P.C.Board Setting Test Run U-4LE2E5, U-5LE2E5, U-6LE2E5 SW 1 SW 2 STOP SW 3 MODE SW 4 A. ADD CN-SILENT CN-RC LED 1 LED 2 CN-TERMINAL CN-ROM CN-OC CN-EMG U-4LE2E8, U-5LE2E8, U-6LE2E8 LED 1...
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Mini VRF SYSTEM CN-OC 3. Main Outdoor Unit P.C.Board Setting Test Run CN-EMG ● Name and Function of Each Switch on Outdoor Unit Control P.C. Board Function Switch Remarks Changes to cooling/heating mode. When in normal operation: When short circuited the COOL side, indoor unit operation in the same refrigerant system changes to all cooling mode.
Mini VRF SYSTEM 4. Auto Address Setting Test Run 4. Auto Address Setting Example: Basic Wiring Diagram (1) • Case of no link wiring 3P terminating (Inter-unit control wiring is not connected to a multiple system.) resistance pin Indoor unit address setting is possible without starting the compressor. (SHORT side) Unit 1 setting (outdoor main unit) * It is not necessary to control the terminating...
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Mini VRF SYSTEM 4. Auto Address Setting Test Run Example: Basic Wiring Diagram (2) • Case of link wiring * See the section “ATTENTION!”. Setting of terminal pin (CN-TERMINAL) No. 1 refrigerant system Refrigerant circuit No. 1 Unit No. 1 (Main) : short-circuit (at shipment) Unit 1 setting (outdoor main unit) Refrigerant circuit No.
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Mini VRF SYSTEM 4. Auto Address Setting Test Run Between conductors ● Final check before operation Wire Final check must be done under the conditions of inter-outdoor unit control wiring connected to the centralized control system and the resistor between conductors must be measured by a Megger.
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Mini VRF SYSTEM 4. Auto Address Setting Test Run Auto Address Setting from the High-spec Wired Remote Controller (CZ-RTC5A / CZ-RTC5B) 1 Keep pressing the buttons simultaneously for 4 or more seconds. The “Maintenance func” screen appears on the LCD display. 2 Press the button to see each menu.
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Mini VRF SYSTEM 4. Auto Address Setting Test Run Display During Auto Address Setting ● On the surface of outdoor unit control P.C. board * Do not short circuit the A.ADD pin again during auto address setting. LEDs 1 and 2 go out and address setting is interrupted. * When auto address setting is normally completed, both LEDs 1 and 2 go out.
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Mini VRF SYSTEM 4. Auto Address Setting Test Run Checking the indoor unit addresses Use the remote controller to check the indoor unit address. CZ-RTC5A / CZ-RTC5B (High-spec wired remote controller) 1 Keep pressing the buttons 3 The “Simple settings” screen appears on the LCD display. simultaneously for 4 or more seconds.
Mini VRF SYSTEM 5. Setting Test Run Remote Controller Test Run 5. Setting Test Run Remote Controller CZ-RTC5A / CZ-RTC5B (High-spec wired remote controller) 20:30 (THU) 1 Keep pressing the buttons simultaneously for 4 or more seconds. The “Maintenance func” screen appears on the LCD display. START Maintenance func 20:30 (THU)
6. Caution for Pump Down Mini VRF SYSTEM Test Run 7. Self-Diagnosis Function Table and Contents of Alarm Display 6. Caution for Pump Down Pump down means refrigerant gas in the system is returned to the outdoor unit. Pump down is used when the unit is to be moved, or before servicing the refrigerant circuit. (See the section 3) This outdoor unit cannot collect more than the rated refrigerant amount as shown by the ●...
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Mini VRF SYSTEM 7. Self-Diagnosis Function Table and Contents of Alarm Display Test Run • If the alarm display “E15”, “E16” and “E20” appear after auto address setting began, check the following items. Alarm display Alarm contents Recognized number of indoor units at the time of auto address setting are fewer than that of indoor units set by SW3 and SW4 on outdoor main unit P.C.
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Mini VRF SYSTEM 7. Self-Diagnosis Function Table and Contents of Alarm Display Test Run Remote control display Alarm contents Two or more indoor units are set as main, in the group controlled indoor units. Fewer indoor units are found in Auto Addressing than the setting on outdoor PCB. More indoor units are found in Auto Addressing than the setting on outdoor PCB.
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Mini VRF SYSTEM 7. Self-Diagnosis Function Table and Contents of Alarm Display Test Run • Contents of alarm display on remote controller For the remote controller, there are other alarm contents listed on the following table besides the alarm display on outdoor main unit control P.C.
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Mini VRF SYSTEM 7. Self-Diagnosis Function Table and Contents of Alarm Display Test Run ATTENTION! Adjustment of terminating resistance (pin) is necessary. Communication failure will occur unless adjustment is made correctly. • Terminating resistance (pin) is mounted on outdoor unit control P.C. board. •...