Order No.SM830226-11CE Model No. Outdoor Unit Class 10HP 12HP 14HP 16HP Model Name U-8MF2E8 U-10MF2E8 U-12MF2E8 U-14MF2E8 U-16MF2E8 Indoor Unit Class S-22MU1E51 S-28MU1E51 S-36MU1E51 S-45MU1E51 S-56MU1E51 S-60MU1E51 S-73MU1E51 S-106MU1E51 S-140MU1E51 S-160MU1E51 4-Way Cassette S-90MU1E51 S-22MU1E5 S-28MU1E5 S-36MU1E5 S-45MU1E5 S-56MU1E5 S-73MU1E5...
Permission from the power supplier is required when • Highly dangerous electrical voltages are used in this system. installing the U-8MF2E8 outdoor unit that is connected Carefully refer to the wiring diagram and these instructions to a 16 A distribution network.
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…In an Area with High Winds • Do not touch the air inlet or the Securely anchor the outdoor unit down with bolts and a sharp aluminum fins of the CAUTION outdoor unit. You may get injured. metal frame. Provide a suitable air baffle. …In a Snowy Area (for Heat Pump-type Systems) •...
The standards for minimum room volume are as follows. Check of Density Limit (1) No partition (shaded portion) The room in which the air conditioner is to be installed requires a design that in the event of refrigerant gas leaking out, its density will not exceed a set limit. The refrigerant (R410A), which is used in the air conditioner, is safe, without the toxicity or combustibility of ammonia, and is not restricted by laws imposed to protect the ozone layer.
Precautions for Installation Using New Refrigerant 1. Care regarding tubing 1-1. Process tubing Material: Use C1220 phosphorous deoxidized copper specified in JIS H3300 “Copper and Copper Alloy Seamless Pipes and Tubes.” For tubes of ø22.22 or larger, use C1220 T-1/2H material or H material, and do not bend the tubes. Tubing size: Be sure to use the sizes indicated in the table below.
IMPORTANT INFORMATION REGARDING THE REFRIGERANT USED This product contains fluorinated greenhouse gases covered by the Kyoto Protocol. Do not vent gases into the atmosphere. Refrigerant type: R410A value: 1975 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.
3WAY SYSTEM Control Functions 1. CONTROL FUNCTIONS 1. Introduction ........................2. Selecting Outdoor Unit for Operation ................Compressor Control ...................... Output of PCB ......................1-13 Outdoor Fan Control ....................1-19 Indoor Units Control from the CCU ................1-23 Tube Refrigerant Recovery Control ................
3WAY SYSTEM 1. Introduction Control Functions The 3WAY System is a system that allows multiple outdoor units to be connected. The outdoor units all contain inverter compressors, and the system does not utilize the sub units that were used in earlier systems. The outdoor unit where the unit No.
3WAY SYSTEM 2. Selecting Outdoor Unit for Operation Control Functions 2-1. Outdoor Unit Operating Rules All outdoor units in this system contain an inverter compressor. Therefore there is no order of priority for the outdoor units. 2-2. Delayed Start of Outdoor Units 2-2-1.
3WAY SYSTEM 3. Compressor Control Control Functions 3-1. Compressors Mounted in the Outdoor Units [U-8MF2E8, U-10MF2E8, U-12MF2E8, U-14MF2E8, U-16MF2E8] 8 hp 10 hp 12 hp 14 hp 16 hp Compressor 1 DC Inverter Rotary 10HP 10HP 10HP 10HP 10HP Installed...
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3WAY SYSTEM 3. Compressor Control Control Functions 3-2-4. Stopping Compressors Situation in which multiple compressors stop All compressors stop at the same time when all indoor units stop or defrosting operation is done. * The stop of the compressor might shift for about ten seconds by the time lag of the communication between outdoor units.
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3WAY SYSTEM 3. Compressor Control Control Functions 3-6. Capacity Control (Roadmap control) The capacity control by the compressors is performed according to the pressure sensor attached to the outdoor unit and temperature thermistor attached to the indoor / outdoor unit heat exchanger. * With roadmap control, the pressure detected by the pressure sensor is converted to saturation temperature before it is used by microcomputer.
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3WAY SYSTEM 3. Compressor Control Control Functions 3-6-2. Condensation Temperature Adjustment by Roadmap Control The “B” area’s target temperature is different due to cooling, heating and mixed cooling/heating operation. Target lower temperature Target upper temperature (Tc_tgt_min) (Tc_tgt_max) Cooling 53.0°C 55.0°C Heating 48.0°C 51.0°C...
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3WAY SYSTEM 3. Compressor Control Control Functions 3-6-3. Cooling Operation with Low Ambient Temperature When operating in cooling mode with the ambient temperature less than 21°C, the unit is set in low ambient temperature cooling mode. During low ambient temperature cooling mode, the heat exchanger capacity control is performed in addition to the compressor capacity control.
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3WAY SYSTEM 3. Compressor Control Control Functions Compressor Control Table Condensation Temp. [Tc] High not_UP slow_UP Target STOP DOWN not_UP Evaporation temperature (Te) and condensation temperature (Tc) areas A, B, C, and D are the same as for evaporation temperature control and condensation temperature control. (2) Increasing/decreasing the heat exchanger capacity (when the outdoor unit heat exchanger is functioning as a condenser) •...
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3WAY SYSTEM 3. Compressor Control Control Functions (3) Increasing/decreasing the heat exchanger capacity (when the outdoor unit heat exchanger is functioning as an evaporator) • Primarily when both the evaporation temperature (Te) and condensation temperature (Tc) are low This occurs when the cooling capacity (heat intake) is high and the heating capacity (heat discharge) is low. The outdoor heat exchanger capacity is increased, increasing the system evaporation capacity and raising the evaporation temperature (Te).
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3WAY SYSTEM 3. Compressor Control Control Functions 3-7. Protection Control 3-7-1. Compressor discharge temperature protection The compressor capacity is controlled according to the table below. *Discharge temperature that is used for this control is the highest temperature among all compressors. Discharge temp.
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3WAY SYSTEM 3. Compressor Control Control Functions 3-7-4. Primary Current Protection of HIC Board The fan motor current is included in primary current. PCB is protected from the power consumption increase of fan motor when the heat exchanger is blocked by frost, etc. 8 hp 10 hp 12 hp...
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3WAY SYSTEM 4. Output of PCB Control Functions 4-2. SAVE Valve [SAVE] This valve turns ON for 5 seconds before the inverter compressor starts. After the inverter compressor starts, the valve is ON for ten seconds. Then it turns OFF. This valve turns ON for 30 seconds after the outdoor unit stops.
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3WAY SYSTEM 4. Output of PCB Control Functions 4-4. Refrigerant Balance Valve [RBV] The main purpose of this valve is to detect the flow of refrigerant (refrigerant volume) on the indoor unit when the outdoor unit heat exchanger is functioning as an evaporator. When the valve determines that there are signs of excess refrigerant, refrigerant is recovered at the receiver tank.
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3WAY SYSTEM 4. Output of PCB Control Functions 4-6. By-Pass Valve [BPV] This valve is for pushing the oil in the balance piping into other outdoor unit. This valve turns ON when the oil level of compressor is “2” or “1” in its own outdoor unit and the oil level of compressor is “0”...
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3WAY SYSTEM 4. Output of PCB Control Functions 4-8-3. Expansion Valve for Heat Exchanger Control The configuration of the heat exchangers is different depending on the capacity of the outdoor unit. Operation of electronic control valves during normal unit operation Status of MOV1 MOV2...
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3WAY SYSTEM 4. Output of PCB Control Functions 4-9. SC Circuit Electronic Control Valve [MOV4] 4-9-1. SC Control (Cooling Mode only) During cooling operation, the liquid refrigerant which condenses at the outdoor unit heat exchanger flows into the receiver tank, and SC (sub-cool = supercooling) approaches 0°C. When SC is small and the length of the tubing connecting the indoor and outdoor units is long, the refrigerant flow in the indoor unit will be reduced sig- nificantly.
3WAY SYSTEM 5. Outdoor Fan Control Control Functions 5-1. Fan mode These outdoor units utilize a DC fan motor that can be controlled in a maximum of 15 steps (15 modes). However, fan modes 14 and 15 can only be used if high static pressure mode has been set. * For information concerning EEPROM settings, refer to the field application functions.
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3WAY SYSTEM 5. Outdoor Fan Control Control Functions 5-1-2. Snow Removal Control (1) Independent control of outdoor unit(control for fan crack prevention) This control is intended to prevent snow from accumulating on stopped fans. When the outdoor unit is stopped, the fan motor is forcibly started by the control for fan crack prevention’s fan mode.
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3WAY SYSTEM 5. Outdoor Fan Control Control Functions 5-1-3. Silent Mode This unit includes 2 types of silent modes. See the table under the section “5-1. Fan mode” for maximum fan mode in silent mode. Selecting the silent mode results in operation that gives priority to reducing noise, because these modes involve restrictions on outdoor unit fan modes, the capacity will be somewhat reduced.
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3WAY SYSTEM 5. Outdoor Fan Control Control Functions 5-2. Fixed Initial Fan Mode For the first 30 seconds after operation starts, the mode is fixed at the initial mode which was calculated from the relationship between the ambient temperature and the outdoor unit horsepower. If the outdoor unit horsepower changes dramatically, the initial mode may be recalculated and may be again fixed for 30 seconds.
3WAY SYSTEM 6. Indoor Units Control from CCU Control Functions 6-1. MOV of Indoor Unit 6-1-1. MOV of each Indoor Unit Operation Mode Mode of Outdoor unit Thermostat indoor unit (system) ON/OFF Stop 20 pulses Stop Operating 20 pulses Stop 20 pulses Operating 20 pulses...
3WAY SYSTEM 6. Indoor Units Control from CCU Control Functions 6-2. Solenoid Valve Kit Control [SVK] This device connects the solenoid valve kit which is used to switch between indoor unit cooling/heating for 3-WAY types. In case of special controls, solenoid valve kit performs special operation. For detail, refer to the section “7.
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3WAY SYSTEM 6. Indoor Units Control from CCU Control Functions 6-3-2. Dry mode Indoor unit fan run in the dry mode is controlled from CCU as shown in the below figure. Fan speed set by remote controller Fan speed is “L” when thermostat ON Fan speed is “LL”when thermostat OFF DTi = (Intake temperature of indoor unit) - (Preset temperature in remote controller) 6-3-3.
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3WAY SYSTEM 6. Indoor Units Control from CCU Control Functions EEPROM setting in main outdoor unit CODE: 2B Setting No. 20 minutes 30 minutes (factory preset mode) 40 minutes 50 minutes 60 minutes * The drain pump always operates when the indoor unit is thermostat ON in cooling operation. * Once the drain pump operates, it keeps operating for 20 minutes.
3WAY SYSTEM 7. Tube Refrigerant Recovery Control Control Functions This control is intended to recover refrigerant if refrigerant has accumulated somewhere in the tubing when the units have been stopped for long periods, as well as to compensate for tubing thermal loss during heating start, and is also used for oil recovery.
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3WAY SYSTEM 7. Tube Refrigerant Recovery Control Control Functions Control when outdoor unit heat exchanger is acting as an evaporator (when all units are in heating mode or at start of mixed operation when heating load is high) > _ Control time Minimum 1 minute –...
3WAY SYSTEM 8. Oil Control Control Functions 8-1. Oil Level Oil level Meaning Conditions of oil Judgement Sufficient The compressor contains sufficient oil. There is no problem. Confirm that oil is returned after Slightly low There will be a risk of oil shortage soon. performing the oil recovery control operation.
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3WAY SYSTEM 8. Oil Control Control Functions 8-5. System Oil Recovery Control Special control : System Oil Recovery Control features one of the functions of special control. 8-5-1. Start of System Oil Recovery Control When operating compressor oil level 0 When operating inverter compressor oil level less than 1 is counted with accumulation for up to 60 minutes.
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3WAY SYSTEM 8. Oil Control Control Functions 8-6. Oil Rotation Control The oil rotation control system regularly exchanges oil among the outdoor units regardless of oil level. Oil rotation control is performed every one hour with accumulated operation time among the connected multiple outdoor units only.
3WAY SYSTEM 9. Defrost Control Control Functions 9-1. Defrost Methods This system uses the following 2 defrosting systems. System employs Defrost control method 1 outdoor unit in the refrigerant system Reverse cycle defrost 2 or more outdoor units in the refrigerant system Outdoor unit cycle defrost 9-2.
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3WAY SYSTEM 9. Defrost Control Control Functions 9-3. Frost Detection Frost detection does not occur for 5 minutes after operation starts. (2) Frost is detected when either condition 1 or 2 below is met. Condition 1: L2 line or below is detected twice, each time continuously for 4 minutes, when the compressor is operating.
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3WAY SYSTEM 9. Defrost Control Control Functions Reverse cycle defrost process This reverse cycle defrost process is performed after outdoor units, indoor units and solenoid valve kits are changed to the cooling cycle. Minimum 1 minute – Maximum 15 minutes Control time >...
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3WAY SYSTEM 9. Defrost Control Control Functions 9-5. Outdoor Unit Cycle Defrost Outdoor unit cycle defrost is performed in systems where 2 or more outdoor units are connected to the refrigerant system. With this defrost method, when 1 outdoor unit operates in defrost mode (heat exchanger operating as a condenser), another outdoor unit operates as an evaporator in the same way as in ordinary heating mode.
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3WAY SYSTEM 9. Defrost Control Control Functions : Evaporator operation : Condenser operation : Stop or shut off the refrigerant E→C : Switching from evaporator operation to condenser operation C→E : Switching from condenser operation to evaporator operation Outdoor unit cycle defrost processing Normal Normal Outdoor...
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3WAY SYSTEM 9. Defrost Control Control Functions Indoor unit (expansion valve, solenoid valve kit, fan) Outdoor unit cycle defrost processing Normal Normal Indoor unit operation operation Defrost Defrost delay-start Switch Switch group group control Mode Thermostat Stop *1(Cooling) *2(Heating) *1(Cooling) Expansion *2(Heating) valve...
3WAY SYSTEM 10. Upper Current Limitation Mode (Demand control) Control Functions There are 2 types of control; demand control and infinity limit in the upper current limitation mode. Either of them is controlled by the lower current limitation. The standard value of the limit current is listed in the table below. 8 hp 10 hp 12 hp...
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3WAY SYSTEM 10. Upper Current Limitation Mode (Demand control) Control Functions 10-2. Upper Current Limitation Mode Even if the demand control is not performed, upper current limitation is restricted. Outdoor Unit 8 hp 10 hp 12 hp 14 hp 16 hp Limited ratio against standard value 140% 140%...
3WAY SYSTEM 11. Alarm Information Control Functions 11-1. Discharge Temperature 11-1-1. Discharge Temperature Protection The upper limit discharge temperature is 106°C for all compressors. When the discharge temperature reaches 106°C, that compressor is stopped and restarted. If the same high discharge condition occurs 5 times, then an alarm occurs. After a compressor has stopped, that compressor will not operate until the temperature has dropped to or below the start-prohibit temperature.
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3WAY SYSTEM 11. Alarm Information Control Functions 11-2. Current Protection 11-2-1. Inverter Compressor and Inverter Fan Motor Alarm Description Compressor 1 primary current detected over-current higher than values. The fan motor current is included in primary current. Compressor 1 secondary current detected over-current higher than values. Occurs when missing phase or over-current is detected at inverter compressor start.
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3WAY SYSTEM 11. Alarm Information Control Functions 11-3. Pressure Sensor Failure This system contains 2 types of pressure sensors: a high-pressure sensor and a low-pressure sensor. 11-3-1. High-Pressure Sensor Failure When the high-pressure sensor becomes an electrical open-circuit or a short-circuit conditions, and a broken wiring, short-circuit or poor connection to the PCB in the high-pressure sensor circuit for 30 seconds or leaves the valve close.
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3WAY SYSTEM 11. Alarm Information Control Functions 11-5. Temperature Sensor Failure When the temperature sensor fails or do not connect with PCB, “F” alarm occurs (excluding discharge temperature sensor for compressor). Alarm display EXG1 Gas temperature sensor in heat exchanger 1 EXL1 Liquid temperature sensor in heat exchanger 1 AIR TEMP...
3WAY SYSTEM 12. Backup Operation Control Functions 12-1. Automatic Backup Operation This system includes a function for automatic backup operation. An alarm is displayed on the remote controller to inform the user that a failure has occurred. 12-1-1. Alarms That Result in Automatic Backup Operation When the following alarm occurs, automatic backup operation is engaged.
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3WAY SYSTEM 12. Backup Operation Control Functions Alarm list 2 (Backup operation continues as long as the problem doesn't solve) Alarm display Discharge temperature sensor failure for compressor 1 Discharge temperature sensor failure for compressor 2 Gas temperature sensor in heat exchanger 1 Liquid temperature sensor in heat exchanger 1 Ambient air temperature Suction temperature...
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3WAY SYSTEM 12. Backup Operation Control Functions 12-1-4. Check for Blinks When Automatic Backup Setting When operating the automatic backup by setting the outdoor unit EEPROM, blink check on the remote controller and centralized control systems is enabled to change for non-displayed. EEPROM setting in main outdoor unit CODE: 49 Setting No.
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3WAY SYSTEM 12. Backup Operation Control Functions All compressors of sub outdoor unit are backed up Examples: Combination of 3 outdoor units with 2 compressors Unit No. 1 Unit No. 2 Unit No. 3 Main unit Sub unit Sub unit CCU function Main outdoor unit Sub outdoor unit Sub outdoor unit Number of setting...
3WAY SYSTEM 13. Other Functions Control Functions 13-1. 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. When the set value is 0 or more, the system continues operating even if it is not possible to communicate with the stopped indoor units.
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3WAY SYSTEM 13. Other Functions Control Functions 13-2. Function for Automatic Judgment of Insufficient Refrigerant Gas and Overcharge This system includes a simple function for judging the amount of refrigerant. 13-2-1. Starting refrigerant level judgment mode Short-circuit the CHK pin on the No. 1 outdoor for 4 seconds or longer to engage this mode. (The LED on the outdoor unit PCB begins blinking.) 13-2-2.
3WAY SYSTEM 14. Detail setting in EEPROM of outdoor unit Control Functions Never use the DN code unlisted in the following table. (P) : Factory preset mode Item Setting No. 0=No sensor & control (P) 1=Sensor & control Operation for using snowfall sensor 2=No sensor &...
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3WAY SYSTEM 14. Detail setting in EEPROM of outdoor unit Control Functions Never use the DN code unlisted in the following table. (P) : Factory preset mode Item Setting No. 20=20min.. 21=21min. ,,,,, The minimum operating time 1 until defrosting 40=40min.
3WAY 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 (Fig.1) •...
3WAY SYSTEM 2. Discharging Compressor Oil Outdoor Unit Repair Procedures Discharged oil can be used for checking the condition of the system. Based on the appearance and color of the discharged oil, a judgment can be made on whether the system is operating normally or not. 2-1.
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3WAY SYSTEM 2. Discharging Compressor Oil Outdoor Unit Repair Procedures 2-2. Discharging Oil in Compressor Recover the refrigerant in the outdoor unit following the procedures in “4. Recovering Refrigerant.” Remove the compressor and discharge the oil in it. Refer to “9. Compressor” for detailed procedures. 2-3.
3WAY SYSTEM 3. Backup Operation Outdoor Unit Repair Procedures This system includes an emergency automatic backup function that allows the A/C to operate during the period after trouble occurs until repairs are made. However, during repair and at other times, use manual backup operation. 3-1.
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3WAY SYSTEM 3. Backup Operation Outdoor Unit Repair Procedures After recovery work is completed, wire the communication lines between indoor CAUTION and outdoor units again. If it not finished yet, an alarm is emitted immediately. (2) Adjusting the refrigerant for backup operation During backup operation, all of the service valves on the failed unit are closed.
3WAY SYSTEM 4. 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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3WAY SYSTEM 4. Recovering Refrigerant Outdoor Unit Repair Procedures 4-2. 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 4-2-1.
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3WAY SYSTEM 4. Recovering Refrigerant Outdoor Unit Repair Procedures (2) If the remote controller (CZ-RTC2) is not available for maintenance of the outdoor unit 1 Determine the outdoor unit where the unit No. setting (SW5) (3P DIP switch) (Blue) on the outdoor unit control PCB is set to No.
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3WAY SYSTEM 4. Recovering Refrigerant Outdoor Unit Repair Procedures 4-2-3. 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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3WAY SYSTEM 4. Recovering Refrigerant Outdoor Unit Repair Procedures Low-pressure outlet port (for ø7.94mm-dia connector) Oil balance tube service port (For 7.94mm-dia. connector) Manifold gauge High-pressure outlet port (for ø7.94mm-dia connector) Refrigerant Liquid tube service port recovery unit (for ø7.94mm-dia connector) Discharge tube service port Refrigerant recovery cylinder (for ø7.94mm-dia connector)
3WAY SYSTEM 5. Checking for Leakage After Repair Outdoor Unit Repair Procedures 5-1. 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 tubes, liquid tube, and balance tube in the repaired outdoor unit (units necessary to carry out the pressurized leak check) are fully closed.
3WAY SYSTEM 6. 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. 6-1. Evacuating Repaired Outdoor Unit (1) Check that each service valve of the gas tubes, liquid tube, and balance 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.
3WAY SYSTEM 7. Charging Compressor Oil Outdoor Unit Repair Procedures 7-1. 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. The oil charging procedures are given below.
3WAY SYSTEM 7. Charging Compressor Oil Outdoor Unit Repair Procedures Close Open Upper valve Manifold gauge Close Open Lower valve Vacuum pump Vacuum pump Fig. 10 When the predetermined amount of oil has been charged into the oil-charging tank, immediately close the lower valve.
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3WAY SYSTEM 7. Charging Compressor Oil Outdoor Unit Repair Procedures Next follow the instructions in “4-2-1. Cooling operation (for all units)” at the outdoor unit where oil will be charged, and start cooling operation at all units. When the operating conditions have stabilized, perform steps 1, 2, and 3 in sequence and open the valves.
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Fig. 13 7-3. Charging Additional Compressor Oil (after replacing compressor) The rated amount of oil is pre-charged in the compressors as given below: Model name Compressor model Q'ty Pre-charged amount of oil (liters) U-8MF2E8 5JD650ZBA22 U-10MF2E8 5JD650ZBA22 5JD650ZBA22 U-12MF2E8 C-SDN453H8B...
3WAY SYSTEM 8. Pumping Out Refrigerant from Outdoor Unit Outdoor Unit Repair Procedures 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. This work is performed in order to collect the refrigerant from an outdoor unit where repairs (other than compressor replacement) will be performed into other outdoor units and indoor units, and the refrigerant tubing.
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3WAY SYSTEM 8. Pumping Out Refrigerant from Outdoor Unit Outdoor Unit Repair Procedures (8) Short-circuit the vacuum application pin on the outdoor unit control PCB of the unit to be repaired. Then turn ON the outdoor unit power. When the vacuum application pin is short-circuited and the power is turned ON, all CAUTION solenoid valves in the outdoor unit are forced open, allowing the refrigerant to be recovered from all tubes which are separated by solenoid valves.
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3WAY SYSTEM 8. Pumping Out Refrigerant from Outdoor Unit Outdoor Unit Repair Procedures (9) Close the gas tube and balance tube on the outdoor unit to be repaired. Then slowly close the liquid tube ser- vice valve. * When the low pressure at the outdoor unit to be repaired reaches 0.5 MPa or below, pull out the SCT connec- tor (2P) (YEL) (CN65) from the outdoor unit control PCB of that outdoor unit.
[H03] (INV compressor) Compressor 2 [H11] [H12] [H13] U-8MF2E8, U-10MF2E8 (Constant-speed compressor 1) A judgment is made based on factors that include the following: Coil resistance (varies depending on the compressor), insulation resistance, current, leakage breaker operation, oil and refrigerant fouling, odor, pressure, and noise...
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3WAY SYSTEM 9. Compressor Outdoor Unit Repair Procedures 9-2. Replacing the Compressor(s) 9-2-1. Replacing only the failed compressor (1) If backup operation is required, follow the instructions in “3. Backup Operation” and engage backup operation. (2) Follow the instructions in “9-3. Removing Compressor” and replace the failed compressor. (3) Fully close the high- and low-pressure gauge valves on the manifold gauge, then stop the vacuum pump.
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3WAY SYSTEM 9. Compressor Outdoor Unit Repair Procedures 9-2-2. Replacing all compressors in a failed unit (1) Follow the instructions in “2. Discharging Compressor Oil” and drain the oil from the oil separator in the failed unit. Measure the amount of drained oil. (2) If backup operation is required, follow the instructions in “3.
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3WAY SYSTEM 9. Compressor Outdoor Unit Repair Procedures 9-2-3. Replacing all compressors in a system (1) Follow the instructions in “2. Discharging Compressor Oil” and drain the oil from the oil separators in all out- door units. Measure the amount of drained oil. (2) Follow the instructions in “9-3.
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3WAY SYSTEM 9. Compressor Outdoor Unit Repair Procedures 9-2-4. Dry core cleaning If burning or other failures occur repeatedly at compressors within the same system, 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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3WAY SYSTEM 9. Compressor Outdoor Unit Repair Procedures (16) After evacuating all nitrogen gas from the tubing, apply vacuum to all outdoor units where dry cores were removed until the pressure is –101kPa (–755 mmHg, 5 Torr) or less. (17) INSTALLATION: Refer to the “Information for the Person in Charge of Installation” items. Charge with an amount of refrigerant equal to the amount that was recovered.
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3WAY SYSTEM 9. Compressor Outdoor Unit Repair Procedures 9-3. Removing Compressors When removing and installing compressors, use sufficient caution to ensure that moisture or other substances do not enter the refrigerant tubing system. 9-3-1. Removing Compressors (for all models) (1) After retrieving refrigerant from the system, perform nitrogen gas replacement on the service port of the gas side service valve.
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3WAY SYSTEM 9. Compressor Outdoor Unit Repair Procedures 9-3-2. Removing Constant-Speed Compressors (for 12, 14 and 16 horse power models) After retrieving refrigerant from the system, perform nitrogen gas replacement on the service port of the gas side service valve. Remove the insulator that the compressor is surrounded.
3WAY SYSTEM 1. Overview Outdoor Unit Maintenance Remote Controller [Service Checker Section] OUTDOOR UNIT MAINTENANCE REMOTE CONTROLLER (CZ-RTC2) for 3WAY SYSTEM 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.
3WAY SYSTEM 2. Functions Outdoor Unit Maintenance Remote Controller 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 • Test run of all indoor units •...
3WAY SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller 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 RC (3P, BLU) PCB connector (3P, BLU) Special service checker wiring...
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3WAY SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller All units start/stop (Fig. 1) <Operation> (ON/OFF operation) button can be used to start and stop all the indoor units. • The LED turns ON when 1 or more indoor units is operating.
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3WAY SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller Display (functions) • Use the temperature setting buttons to change the item code. Item code Item Remarks Outdoor unit alarm Alarm code display No. of connected indoor units Quantity Unit Nos.
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3WAY SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller (3) XX-YY R.C. Locations where , and are displayed Displays the outdoor unit sub-bus address which is as shown in Fig. 3. currently selected. XX = Outdoor system address on main bus line (1 – 30) YY = Outdoor unit sub-bus address (1 –...
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3WAY SYSTEM 3. Ordinary Display Controls and Functions Outdoor Unit Maintenance Remote Controller Concerning the 7-segment, 4-digit display remote controller timer display The connected unit Nos. are displayed as shown below, using the 7-segment 4-digit ( ) display and the colon. Display for unit Nos.
3WAY 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 buttons simultaneously for 4 seconds or longer to switch to temperature monitor mode. During temperature monitoring, is lit.
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3WAY SYSTEM 4. Monitoring Operations Outdoor Unit Maintenance Remote Controller Display of unit No. 1 (main unit) Description Remarks Intake temp. °C °C °C °C Indoor unit Discharge temp. °C Discharge temp. setting °C Indoor unit electronic control valve position STEP Discharge temp.
3WAY SYSTEM 5. Outdoor Unit Alarm History Monitor Outdoor Unit Maintenance Remote Controller • Displays outdoor unit alarms only. Does not display indoor unit alarms. • Check the indoor unit alarm histories separately using the indoor unit remote controllers or other control device. <Operating procedure>...
3WAY SYSTEM 6. Mode Settings Outdoor Unit Maintenance Remote Controller Setting mode 1 Display of first 4 digits <Operating procedure> Press and hold the (CHECK) button and (VENTILATION) button simultaneously for 4 seconds or longer. Use the temperature setting buttons to change the item code. The item codes and setting data are shown in the table below.
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3WAY SYSTEM 6. Mode Settings Outdoor Unit Maintenance Remote Controller Setting mode 2 <Operating procedure> Press and hold the (CHECK) button, button, and button simultaneously for 4 seconds or longer. Use the temperature setting buttons to change the item code. The item codes and setting data are shown in the table below. Use the timer time buttons to change the setting data.
3WAY SYSTEM 1. Simple Settings Function Remote Controller Functions • This allows the filter lifetime, operating mode [Remote Controller Functions Section] priority change, central control address, and other settings to be made for an individual or group- control indoor unit to which the remote controller used for simple settings is connected.
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3WAY 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 (fitlter life time) 0003 5,000 hours 0004 10,000 hours 0005 Use the filter clogging sensor.
3WAY 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 connected.
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3WAY SYSTEM 2. Detailed Settings Function Remote Controller Functions Setting the Flap Separately (When setting the CZ-RTC2) Press the timer time buttons to select 1) The 4-air outlet flap can be adjusted separately during the desired setting data. operation. When not adjusted separately, all flaps operate Flap position in the same manner.
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3WAY SYSTEM 2. Detailed Settings Function Remote Controller Functions List of Detailed Setting Items Setting data Item code Item Description Description Description 4-Way Casstte (60×60) 0001 0002 2-WAY Cassette (L1) 0003 1-Way Cassette (D1) (U1, Y1) Low Silhouette Ducted (F1,F2) High Static Pressure Type 0005...
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3WAY 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 –10°C –009 –9°C Cooling discharge –008 –8°C temperature shift 0010 10°C –010 –10°C –009 –9°C Heating discharge...
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3WAY 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. 0000 Not used.
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3WAY SYSTEM 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 Fan tap setting static-pressure filter...
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3WAY SYSTEM 2. Detailed 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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3WAY SYSTEM 2. Detailed 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) (1) Explanation of operation mode priority change Enabled only in 2WAY System heat-pump models.
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3WAY SYSTEM 2. Detailed 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...
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3WAY 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. These must be set after installation if automatic address setting is not Indoor unit address performed.
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3WAY 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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3WAY SYSTEM 2. Detailed Settings Function 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.
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3WAY SYSTEM 3WAY SYSTEM 2. Detailed Settings Function 2. Detailed Settings Function Remote Controller Functions Remote Controller Functions Selecting the DC fan motor tap (when setting from the PCB) 4-Way Cassette type <Procedure> Stop the system before performing these steps. Open the electrical component box cover, then check the indoor unit control PCB.
3WAY 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. List of Servicing Functions Functions Description Button operation Reset operation Unit status Operation with Press and hold the button...
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3WAY SYSTEM 3. Remote Controller Servicing Functions Remote Controller Functions Test Run Function Operates the unit with the thermostat forced ON. <Procedure> Press and hold the button for 4 seconds or longer. “Test” appears on the remote controller LCD display (Fig. 3). Start operation.
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3WAY SYSTEM 3. Remote Controller Servicing Functions Remote Controller Functions Sensor Temperature Display Function (displayed regardless of whether unit is operating or stopped) The procedure below displays the sensor temperatures from the remote controller, indoor unit, and outdoor unit on the remote controller. <Procedure>...
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3WAY SYSTEM 3. Remote Controller Servicing Functions Remote Controller Functions Indoor unit sensors Outdoor unit sensors Unit No.1 Unit No.2 Unit No.3 Intake temp. Discharge temp. 1 Discharge temp. 2 High-pressure sensor temp. Heat exchanger gas 1 Heat exchanger liquid 1 Discharge temp.
3WAY SYSTEM 1. Contents of Remote Controller 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 Error in receiving serial communication signal. Operating lamp communication error signal from indoor unit.
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3WAY SYSTEM 1. Contents of Remote Controller Trouble Diagnosis Switch Alarm Display Blinking: OFF: Wired Wireless remote remote controller control receiver display display Possible cause of malfunction Thermistor fault Indoor thermistor is either Indoor coil temp. sensor (E1) <<F01>> Operating and open or damaged.
3WAY SYSTEM 2. Outdoor Unit Control Panel LED Display Trouble Diagnosis : ON : Blinking : OFF) LED (RED) Display meaning After the power is turned ON (and automatic 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 automatic address setting is not in progress), 1 or more indoor units are confirmed in that system;...
3WAY SYSTEM 3. Remote Controller Servicing Functions Trouble Diagnosis Sensor temperature display function (displayed both when unit is running and stopped) • Use the following check procedure to display the sensor temperatures from the remote controller, indoor unit, and outdoor unit sensors on the remote controller display.
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3WAY SYSTEM 3. Remote Controller Servicing Functions Trouble Diagnosis Sensor Temperature Relationship Table Location where sensor Sensor address Sensor type Sensor address Sensor type is installed Remote controller temperature Discharge temperature sensor Indoor unit intake temperature Discharge temperature setting Indoor unit heat exchanger Indoor unit electronic expansion Indoor unit temperature (E1)
3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis With types 8HP and 10HP, the INV compressor is compressor 1. With types 12HP, 14HP and 16HP, the INV compressor is compressor 1, and the constant-speed compressors (AC1) are compressors 2. Alarm code Alarm meaning Page Outdoor unit failed to receive serial communication signals from indoor unit.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis E06 Alarm Alarm code Alarm meaning Outdoor unit failed to receive serial communication signals from indoor 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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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis E16 Alarm Alarm code Alarm meaning Automatic address setting alarm (too many units) Alarm conditions • The number of indoor units was too many when automatic address setting was performed. • After initial communications were completed, an unrecognized unit was detected. Probable cause (1) The number of indoor units set at the indoor unit quantity setting SW (SW3, SW4) on the outdoor unit PCB is less than the number set.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis E25 Alarm Alarm code Alarm meaning Outdoor unit address setting failure (duplication) Alarm conditions Communication by inter-outdoor unit control wiring was received that contained the same address as that unit 5 times or more within 3 minutes. Probable cause The unit number is set incorrectly.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis F04, F05 Alarm Alarm code F04, F05 Alarm meaning Compressor 1 discharge temperature sensor trouble, compressor 2 discharge temperature sensor trouble. 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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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis Check (3) Leakage from the discharge tube check valve Trouble: Although the other compressor is operating and this compressor is stopped, the discharge temperature of this compressor rises together with the temperature of the other compressor.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis F08 Alarm Alarm code Alarm meaning Outdoor air temperature sensor trouble Alarm conditions (1) A/D step is 10 steps or less (short circuit). (2) A/D step is 1014 steps or more (open circuit) Probable cause (1) Sensor malfunction (including connector) (2) PCB malfunction...
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis F16 Alarm Alarm code Alarm meaning High-pressure sensor malfunction Alarm conditions • High-pressure sensor disconnected or open circuit • High-pressure sensor detected over 3.6MPa continuously for 30 minutes while outdoor units stopped. •...
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis F17 Alarm Alarm code Alarm meaning Low-pressure sensor trouble Alarm conditions (1) Sensor short circuit (2) Sensor open circuit Probable cause (1) Sensor malfunction (including connector) (2) PCB malfunction Check (1) Measure the sensor resistance. Check that the sensor is operating normally. (2) Use a remote monitor or a PC monitor to check the temperature that is recognized by the microcomputer.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis H11, H12 Alarm Alarm code H11, H12 Alarm meaning H11: Constant speed compressor 2 overcurrent alarm H12: Constant speed compressor 2 lock current alarm Alarm conditions H11: During operation, when the compressor current value exceeds the following values for 30 seconds or longer listed below table.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis H03, H13 Alarm Alarm code H03, H13 Alarm meaning H03 : Compressor 1 CT sensor disconnected or short-circuit H13 : Compressor 2 CT sensor disconnected or short-circuit Alarm conditions Compressor 1: When the compressor 1(INV) is stopped, the primary current detected over 18A. When the frequency of compressor 1(INV) is over 35Hz and the secondary current is over 7.0A, the primary current detected lower than 0.7A.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis H06 Alarm Alarm code Alarm meaning Abnormal decrease of low-pressure Alarm conditions • Low-pressure sensor detects lower than 0.06MPa continuously for 2 minutes or lower than 0.02MPa for just a moment. Probable cause (1) Low-pressure sensor failure (2) Failure to open the service valve of the outdoor unit (3) Clogged refrigerant circuit...
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis H08, H27 Alarm Alarm code H08, H27 Alarm meaning Trouble (open circuit) with the oil sensor (connection) at compressor 1 and compressor 2 Alarm conditions This alarm occurs when a connector connection (pins 1 and 2 for compressor 1, pins 4 and 5 for compressor 2) is open.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis L10 Alarm Alarm code Alarm meaning Outdoor unit capacity not set Alarm conditions The outdoor unit capacity has not been set, or the setting is not allowed by the system. Probable cause This alarm occurs because the capacity has not been set.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis L17 Alarm Alarm code Alarm meaning Outdoor unit model mismatch Alarm conditions This alarm occurs when a unit other than R410A refrigerant model is connected. Probable cause (1) A unit that uses R407C refrigerant, or a R22 model unit, was connected by mistake. (2) The connected unit is correct, however the refrigerant type setting in the outdoor unit EEPROM (item code 80) is incorrect.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis P03, P17 Alarm Alarm code P03, P17 P03 : Compressor 1 discharge temperature trouble Alarm meaning P17 : Compressor 2 discharge temperature trouble Alarm conditions Compressor 1 : Pre-trip stops when the temperature exceeds 106°C. Compressor 2 : Pre-trip stops when the temperature exceeds 106°C.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis P04 Alarm Alarm code Alarm meaning High-pressure switch activated. Alarm conditions The operation of the electronic circuit in the high-pressure switch may short-circuit the terminal depending on the pressure. A pressure of 3.8 MPa or above will short-circuit the terminal. Once the terminal is short-circuited, it will remain in that state until the pressure goes below 3.15 MPa.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis P14 Alarm Alarm code Alarm meaning sensor operation (1) It is judged an error whenever the outdoor unit receives the signal “O Alarm Generated” Alarm conditions from the indoor unit. (2) With the indoor unit's EEPROM setting (item code 0B) set to 0001, the EXCT input was shorted.
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3WAY SYSTEM 4. 3WAY Alarm Codes Trouble Diagnosis P22 Alarm Alarm code Alarm meaning Fan motor trouble Alarm conditions Fan motor start failure, fan motor Hall IC input failure Probable cause Possible causes are a Hall IC input circuit failure and a fan HIC failure. Check Check the fan motor wiring, the Hall IC wiring, and the connector connections.
3WAY SYSTEM 5. Blinking Inspection Display Trouble Diagnosis Currently the blinking inspection display can be displayed only on the wired remote controller CAUTION and system remote controller. Blinking inspection display (1) (Automatic backup) Alarm code (Blinking inspection display) Alarm meaning Automatic backup is in progress.
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3WAY SYSTEM 5. Blinking Inspection Display Trouble Diagnosis Blinking inspection display (2) (compressor magnet SW seizing detection) Alarm code (Blinking inspection display) Alarm meaning Compressor magnet SW seizing detected Status: Although an outdoor unit exists where the outdoor unit fan is running, no compressors in the system are operating.
3WAY SYSTEM 6. Inspection of Parts Trouble Diagnosis (1) High-pressure switch (63PH1, 63PH2, 63PH3) Disconnect the CN3 connector (3P, WHT) from the outdoor unit control panel. 63PH1 Measure the resistance between socket pins 1 and 3. The resistance is OK if the result is 0 Ω. Disconnect the CN4 connector (3P, RED) from the outdoor unit control panel.
3WAY SYSTEM 7. Test Pin Trouble Diagnosis 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 (CN022, WHT), then turn the power back ON. Output is performed in the sequence shown in the table below, for 0.5 seconds each.
3WAY SYSTEM 8. Symptom: Thermostat in OFF continues or Trouble Diagnosis cycles OFF & ON too frequently How to detect abnormality • Abnormality does not occur. Protective function can be checked when the outdoor maintenance remote controller is connected. Error Diagnosis Adjust setting Indoor control Setting temperature reaches the level set ON thermostat.