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TECHNICAL & SERVICE MANUAL CS-KS18NKU + CU-KS18NKU + CU-KS18NKUA CS-KS24NKU + CU-KS24NKU + CU-KS24NKUA DC INVERTER SPLIT SYSTEM AIR CONDITIONER Indoor Model No. Product Code No. Outdoor Model No. Product Code No. CS-KS18NKU 1 852 360 90 CU-KS18NKU 1 852 361 18...
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SAFETY PRECAUTIONS • Before doing repair work, please read the " SAFETY PRECAUTIONS" carefully and fully understand them. • The precautionary items here are divided into " Warning" and " Caution" items. Items in particular which may cause death or serious injury to the service personnel if the work is not performed correctly, are included in the "...
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Warning If refrigerant gas blows off during the work, do not touch the refrigerant gas as it may cause frostbite. Prohibit If refrigerant gas leaks during the work, ventilate the room. If refrigerant gas catches fire, harmful gas may be generated. Do not mix any gas other than the specified refrigerant gas in the refrigerating cycle.
Table of Contents Page 1. OPERATING RANGE ........................2. SPECIFICATIONS 2-1. Unit Specifications ......................2-2. Major Component Specifications ..................2-3. Other Component Specifications ..................3. DIMENSIONAL DATA ........................4. REFRIGERANT FLOW DIAGRAM 4-1. Refrigerant Flow Diagram ....................5. PERFORMANCE DATA 5-1.
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Page 11. REFRIGERANT R410A: SPECIAL PRECAUTIONS WHEN SERVICING UNIT 11-1. Characteristics of New Refrigerant R410A ................. 11-2. Checklist before Servicing ....................11-3. Tools Specifically for R410A ....................11-4. Tubing Installation Procedures .................... 11-5. In Case of Compressor Malfunction ..................11-6. In Case Refrigerant is Leaking ....................
2-2. Major Component Specifications 2-2-1. Indoor Unit Indoor Unit CS-KS18NKU Control PCB Part No. CB-CS-KS18NKU Controls Microprocessor Control Circuit Fuse 250V 3A Type Cross-Flow Q'ty ... Dia. and Length inch (mm) 1 ... D3-5/8 / L33-9/32 (D92/L845) Fan Motor Type DC Motor Model ...
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Indoor Unit CS-KS24NKU Control PCB Part No. CB-CS-KS24NKU Controls Microprocessor Control Circuit Fuse 250V 3A Type Cross-Flow Q'ty ... Dia. and Length inch (mm) 1 ... D3-5/8 / L33-9/32 (D92/L845) Fan Motor Type DC Motor Model ... Q'ty SIC-41CVJ-D847-3 ... 1 No.
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2-2-2. Outdoor Unit Outdoor Unit CU-KS18NKU Control PCB Part No. CB-CU-KS18NKU Controls Microprocessor Control Circuit Fuse 250V 25A Compressor Type DC Twin Rotary (Hermetic) Compressor Model / Nominal Output C-6RVN93H0M / 1,050W Compressor Oil ... Amount Pints (cc) FV50S ... 0.74 (350) Coil Resistance (Ambient Temp.
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Outdoor Unit CU-KS24NKU Control PCB Part No. CB-CU-KS24NKU Controls Microprocessor Control Circuit Fuse 250V 25A Compressor Type DC Twin Rotary (Hermetic) Compressor Model / Nominal Output G8T265FU1JW / 2,410W Compressor Oil ... Amount Pints (cc) FV50S ... 1.49 (700) Coil Resistance (Ambient Temp. 77 °F (25 °C)) U - V : 0.36 V - W :...
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Outdoor Unit CU-KS18NKUA Control PCB Part No. CB-CU-KS18NKUA Controls Microprocessor Control Circuit Fuse 250V 25A Compressor Type DC Twin Rotary (Hermetic) Compressor Model / Nominal Output C-6RVN93H0M / 1,050W Compressor Oil ... Amount Pints (cc) FV50S ... 0.74 (350) Coil Resistance (Ambient Temp. 68 °F (20 °C)) R - S : 0.482 S - T :...
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Outdoor Unit CU-KS24NKUA Control PCB Part No. CB-CU-KS24NKUA Controls Microprocessor Control Circuit Fuse 250V 25A Compressor Type DC Twin Rotary (Hermetic) Compressor Model / Nominal Output G8T265FU1JW / 2,410W Compressor Oil ... Amount Pints (cc) FV50S ... 1.49 (700) Coil Resistance (Ambient Temp. 77 °F (25 °C)) U - V : 0.36 V - W :...
5. PERFORMANCE DATA 5-1. Temperature Charts Indoor Unit CS-KS18NKU Outdoor Unit CU-KS18NKU Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (60Hz, 230V) (1) Low pressure performance chart (1.2) Lo fan Hi Fan (1.1) (1.0) (0.9) (0.8) (0.7) (0.6)
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Indoor Unit CS-KS18NKU Outdoor Unit CU-KS18NKUA Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (60Hz, 230V) (1) Low pressure performance chart (1.2) Lo fan Hi Fan (1.1) (1.0) (0.9) (0.8) (0.7) (0.6) (0.5) (-20) (-15) (-10) (-5) (10) (15) (20)
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Indoor Unit CS-KS24NKU Outdoor Unit CU-KS24NKU Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (60Hz, 230V) (1) Low pressure performance chart (1.2) Lo fan Hi Fan (1.1) (1.0) (0.9) (0.8) (0.7) (0.6) (0.5) (20) (25) (30) (35) (40) Outdoor inlet air DB temp.
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Indoor Unit CS-KS24NKU Outdoor Unit CU-KS24NKUA Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (60Hz, 230V) (1) Low pressure performance chart (1.2) Lo fan Hi Fan (1.1) (1.0) (0.9) (0.8) (0.7) (0.6) (0.5) (-20) (-15) (-10) (-5) (10) (15) (20)
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5-2. Cooling Capacity Indoor Unit : CS-KS18NKU Outdoor Unit : CU-KS18NKU / CU-KS18NKUA Power Supply : 230V Single Phase 60Hz < Cooling Capacity > RATING CAPACITY: 17,500 BTU/h AIR FLOW RATE: 524 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (18.3) (23.9)
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Indoor Unit : CS-KS24NKU Outdoor Unit : CU-KS24NKU / CU-KS24NKUA Power Supply : 230V Single Phase 60Hz < Cooling Capacity > RATING CAPACITY: 24,200 BTU/h AIR FLOW RATE: 659 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (18.3) (23.9) (29.4) (35.0) (40.6) (46.1) 21,050...
6. ELECTRICAL DATA 6. ELECTRICAL DATA 6-1. Electrical Characteristics 6-1. Electrical Characteristics Indoor Unit Indoor Unit CS-KS18NKU CS-KS18NKU Outdoor Unit CU-KS18NKU Outdoor Unit CU-KS18NKU Cooling Cooling < < > > 230V 230V Indoor Unit Indoor Unit Outdoor Unit Outdoor Unit...
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Indoor Unit CS-KS24NKU Outdoor Unit CU-KS24NKU Cooling < > 230V Indoor Unit Outdoor Unit Complete Unit Fan Motor Fan Motor + Compressor Performance at 230V Single-phase 60Hz Rating conditions Running amp. 10.3 10.8 Power input 2,405 2,460 Rating conditions: Indoor air temperature: 80 °F (26.7 °C) DB / 67 °F (19.4 °C) WB Outdoor air temperature: 95 °F (35 °C) DB...
6-2. Electric Wiring Diagrams Indoor Unit CS-KS18NKU CS-KS24NKU To avoid electrical shock hazard, be sure to WARNING disconnect power before checking, servicing and/or cleaning any electrical parts. TERMINAL BASE EVAPORATOR CONNECTOR FLAP FLAP 5P (WHT) LAMP 10P (WHT) FLAP MOTOR CONTROLLER ROOM THERMISTOR ROOM/COIL...
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Outdoor Unit CU-KS18NKU CU-KS18NKUA To avoid electrical shock hazard, be sure to WARNING disconnect power before checking, servicing and/or cleaning any electrical parts. REACTANCE POWER RELAY TERMINAL PLATE FERRITE CORE ACIN1 CONTROLLER ACIN2 SI-A COMP A-TH COIL/OUTDOOR DCFM 1 2 3 4...
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Outdoor Unit CU-KS24NKU To avoid electrical shock hazard, be sure to WARNING disconnect power before checking, servicing and/or cleaning any electrical parts. REACTANCE POWER RELAY TERMINAL PLATE FERRITE CORE ACIN1 CONTROLLER ACIN2 SI-A COMP A-TH COIL/OUTDOOR DCFM 1 2 3 4 1 2 3 4 1 2 3 4 5 6 7 1 2 3 4 5...
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Outdoor Unit CU-KS24NKUA To avoid electrical shock hazard, be sure to WARNING disconnect power before checking, servicing and/or cleaning any electrical parts. REACTANCE 1P-CONNECTOR(WHT) POWER RELAY 1P-CONNECTOR(WHT) TERMINAL CRANKCASE HEATER1 HEATER0 PLATE FERRITE CORE HEATER ACIN1 CONTROLLER ACIN2 SI-A COMP A-TH COIL/OUTDOOR DCFM...
7. MAINTENANCE 7-1. Address Setting of the Remote Control Unit The address can be set in order to prevent interference between remote controllers when two Sanyo indoor units are installed near each other. The address is normally set to "A." To set a different address, it is necessary to change the address on the Fig.
7-2. Disconnecting and Connecting Positive Connector for Outdoor Unit One of the two types of connectors illustrated at left is used. Their basic structure is the same for each. How to Disconnect Hold the resin connector cover, and pull the connector off. You cannot disconnect the connector by pulling the wire since it is locked inside.
8. FUNCTIONS 8-1. Operation Functions Emergency operation SENSOR DRY Emergency operation is available when the remote During DRY operation, the system adjusts the room temperature and fan speed according to the conditions in the controller malfunctions, has been lost, or otherwise room, in order to maintain a comfortable room environment.
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HIGH POWER NIGHT SETBACK This function acts to raise the power but keeps the AC system in When NIGHT SETBACK operation is set, the temperature and the same operating mode. fan speed settings will be adjusted automatically to allow This function is set with the HIGH POWER button on the remote comfortable sleep.
8-2. Protective Functions Compressor discharge temperature control Freeze prevention This function controls the operation frequency to prevent the During COOL or DRY operation, freezing is detected and compressor discharge temperature from rising more than a operation is stopped when the temperature of the indoor heat exchanger matches the conditions below.
9. TROUBLESHOOTING (BEFORE CALLING FOR SERVICE) 9-1. Precautions before Performing Inspection or Repair After checking the self-diagnostics monitor, turn the power OFF before starting inspection or repair. High-capacity electrolytic capacitors are used inside the outdoor unit controller (inverter). They retain an electrical charge (charging voltage DC 310V) even after the power is turned OFF, and some time is required for the charge to dissipate.
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(1) Self-diagnostics Lamps INDOOR UNIT (1) OPERATION lamp (2) TIMER lamp (3) QUIET lamp OPERATION button REMOTE CONTROL receiver Since the indications cover various units, the corresponding parts listed below may not be present in some models..OFF ..BLINKING ..
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(2) If the self-diagnostics function fails to operate No indicators illuminate and the Check the indoor unit. indoor fan does not rotate. Check the power voltage. Blown Is the fuse blown? Normal Replace the circuit board or the fuse. Replace the controller.
9-3. Checking the Indoor and Outdoor Units (1) Checking the indoor unit Control Check items (unit operation) • The rated voltage must be present between inter-unit wirings 1 and 2. Use the remote controller to operate the unit in "TEST run" mode. To determine •...
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(3) Serial Communication Error Identification Procedure If the lamps on the main body show the following conditions after the completion of self-diagnostics, a communication error between the indoor unit and outdoor unit might be considered. In such a case, identify the breakdown section by using the following procedure. NOTE Refer to "Method of Self-Diagnostics"...
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( Continued from the previous page A. ) ( Continued from the previous page B. ) Is the voltage of about DC22V to 24V given between the terminals 2 and 3 on the indoor unit terminal strip (Serial Communication Line) ? (Fig.
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(3-2) Condition: E12 Troubleshooting Serial Communication Outdoor Unit Power 1. Turn off the power and wait until the power lamp (LED) of the outdoor unit controller is turned OFF. 2. Disconnect the cable from the terminal 3 on the Outdoor Indoor Unit unit terminal strip.
9-4. Trouble Diagnosis of Fan Motor 9-4-1. Indoor Fan Motor This indoor DC fan motor contains an internal control PCB. Therefore, it is not possible to measure the coil resistance, and the following procedure should be used to check the motor. To perform diagnosis, operate the unit in cooling mode with indoor fan speed "High".
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Any one of the above measured values is not normal. Outdoor unit controller trouble (Replace the controller .) (Reference) DC motor connector pin arrangement CU-KS18NKU / CU-KS18NKUA CU-KS24NKU / CU-KS24NKUA Pin 1: Vs (white) Pin 1: Vm (red) Pin 2: Not used...
9-5. Noise Malfunction and Electromagnetic Interference An inverter A/C operates using pulse signal control and high frequencies. Therefore, it is susceptible to the effects of external noise, and is likely to cause electromagnetic interference with nearby wireless devices. A noise filter is installed for ordinary use, preventing these problems. However, depending on the installation conditions, these effects may still occur.
10. CHECKING ELECTRICAL COMPONENTS Ground wire 10-1. Measurement of Insulation Resistance Clip The insulation is in good condition if the resistance exceeds 1M ohm. Probe 10-1-1. Power Supply Cord Insulation tester Clamp the grounding wire of power cord with the lead Fig.
10-2. Checking Continuity of Fuse Fuse on PCB Ass'y Remove the PCB Ass'y from the electrical component box. Then pull out the fuse from the PCB Ass'y. (Fig. 5) Check for continuity using a multimeter as shown in PCB Ass'y Fig.
11. REFRIGERANT R410A: SPECIAL PRECAUTIONS WHEN SERVICING UNIT 11-1. Characteristics of New Refrigerant R410A 11-1-1. What is New Refrigerant R410A? R410A is a new refrigerant that contains two types of pseudo-non-azeotropic refrigerant mixture. Its refrigeration capacity and energy efficiency are about the same level as the conventional refrigerant, R22. 11-1-2.
11-2. Checklist before Servicing Use a clutch-type flare tool for R410A or the conventional flare tool. Note that sizes of the resultant flares differ between these two tools. Where a conventional flare tool is used, make sure to observe A Specification (amount of extrusion) by using the flare spacer.
11-3. Tools Specifically for R410A For servicing, use the following tools for R410A Tool Distinction Tool Name Gauge manifold Charging hose Gas leak detector Refrigerant cylinder Charging cylinder Refrigerant recovery unit Vacuum pump with anti-reverse flow (*1) Tools specifically for R410A (Solenoid valve-installed type, which prevents oil from flowing back into the unit when the power is off, is recommended.) Vacuum pump (*2)...can be used if the following adapter is attached.
11-5. In Case of Compressor Malfunction Should the compressor malfunction, be sure to make the switch to a replacement CAUTION compressor as quickly as possible. Use only the tools indicated exclusively for R410A. See "11-3. Tools Specifically for R410A." 11-5-1. Procedure for Replacing Compressor (1) Recovering refrigerant Any remaining refrigerant inside the unit should not be (1) Recover refrigerant...
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(5) Recharging Configuration and characteristics of cylinders Be sure to charge the specified amount of Valve refrigerant in liquid state using the service port of the wide tube service valve. The proper amount is listed on the unit's nameplate. When the entire amount cannot be charged all at once, charge gradually while operating the unit in Cooling Operation.
11-6. In Case Refrigerant is Leaking Never attempt to charge additional refrigerant when refrigerant has been leaking CAUTION from the unit. Follow the procedure described below to locate points of leaks and carry out repairs, then recharge the refrigerant. (1) Detecting Leaks Use the detector for R410A to locate refrigerant leak points.
11-7. Charging Additional Refrigerant 11-7-1. When Tubes are Extended Observe the proper amount of refrigerant as stated in this service manual or the installation manual that came with the indoor unit. Charge additional refrigerant in liquid state only. Never charge additional refrigerant if refrigerant is leaking from the unit. Follow CAUTION instructions given in "11-6.
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Operating Instructions Split System Air Conditioner Model No. Indoor Units Outdoor Units CS-KS18NKU CU-KS18NKU CS-KS24NKU CU-KS18NKUA CU-KS24NKU CU-KS24NKUA This air conditioner uses the refrigerant R410A. Before operating the unit, read these operating instructions thoroughly and keep them for future reference.
FEATURES This air conditioner is an inverter type unit that automatically adjusts capability as appropriate. Details on these functions are provided below; refer to these descriptions when using the air conditioner. • Microprocessor Controlled Operation • Air Sweep Control The interior compartment of the remote controller This function moves a flap up and down in the air outlet, contains several features to facilitate automatic operation, directing air in a sweeping motion around the room and...
INSTALLATION LOCATION • We recommend that this air conditioner be installed properly by qualified installation technicians in accordance with the Installation Instructions provided with the unit. • Before installation, check that the voltage of the electric supply in your home or office is the same as the voltage shown on the nameplate.
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• To prevent possible hazards from insulation failure, the unit must be grounded. • Do not clean inside the indoor and outdoor units by users. Engage authorized dealer or specialist for cleaning. • In case of malfunction of this appliance, do not repair by yourself. Contact to the sales dealer or service dealer for a repair.
NAMES OF PARTS Air Intakes INDOOR UNIT Air Outlet Remote Controller Drain Hose Refrigerant Tubes OUTDOOR UNIT Air Outlet This illustration is based on the external view of a standard model. NOTE Consequently, the shape may differ from that of the air conditioner which you have selected.
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UNIT DISPLAY AND OPERATION BUTTON INDOOR UNIT IMPORTANT OPERATION lamp TIMER lamp Avoid using radio equipment QUIET lamp QUIET such as mobile phone near (within 4 ft (1.2m).) the remote control receiver. Some radio OPERATION button equipment may cause malfunction of the unit. If the trouble happens, disconnect power and restart REMOTE CONTROL receiver...
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REMOTE CONTROLLER (DISPLAY) Displayed when transmitting data Displayed when indoor unit sensor is in use Displayed when setting temperature Displayed when temperature is shown Displayed when setting timer Displayed when the time display is set to 12-hour time. Symbols (1) Operation mode (4) Timer 24-hour clock with ON/OFF MILD DRY ......
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REMOTE CONTROLLER Sensor Transmitter (Cover closed) Display ON/OFF operation button QUIET button 1 HR. TIMER button Temperature setting buttons (TEMP.) MODE selector button FAN SPEED selector button NIGHT SETBACK button FLAP button HIGH POWER button ON TIME Advance button OFF TIME Advance button setting setting...
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REMOTE CONTROLLER (CONTINUED) Temperature setting buttons Press the button to increase the set temperature. (TEMP.) Press the button to reduce the set temperature. The temperature setting changes by 1 °C or 2 °F each time one of the TEMP. buttons is pressed. MODE selector button Use this button to select DRY, COOL or FAN mode.
REMOTE CONTROLLER (CONTINUED) Temperature Display Selector button This switches the temperature display between °C and °F. Time Display Selector button This switches the time display between 24-hour time and 12-hour time. ACL button (ALL CLEAR) Puts the remote controller into pre-operation status. Always press this button after replacing the batteries.
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USING THE REMOTE CONTROLLER (CONTINUED) How to Use the Remote When using the remote controller, always point the unit’s transmitter head directly Controller at the air conditioner’s receiver. Air Conditioner (Indoor unit) Receiver Remote Controller (Transmitter head) Remote Controller Installation The remote controller may be operated either from a non-fixed position or from a Position wall-mounted position.
OPERATION WITH THE REMOTE CONTROLLER 1. Operation STEP 2 STEP 3 STEP 1 STEP 4 STEP 5 NOTE Check that the circuit breaker on the power panel is turned on. Press the setting buttons as described below and change the settings as desired. STEP 1 Press the MODE selector button and select the desired mode.
OPERATION WITH THE REMOTE CONTROLLER (CONTINUED) • Choose the best position in the room for the remote controller, which also acts NOTE as the sensor for room comfort and transmits the operating instructions. Once you’ve found this best position, always keep the remote controller there. •...
OPERATION WITH THE REMOTE CONTROLLER (CONTINUED) 4. Night Setback Mode Night Setback Mode is used for saving energy. Press the NIGHT SETBACK button while unit is operating. (except FAN mode) mark appears in the display. To release the night setback function, press the NIGHT SETBACK button again. NOTE Pressing the MODE selector button cancels Night Setback mode.
OPERATION WITH THE REMOTE CONTROLLER (CONTINUED) 5. QUIET Mode QUIET Mode is used to reduce the fan sound of the indoor unit. Press the QUIET button. mark appears in the display. To cancel, press QUIET button again. • In QUIET Mode, the fan rotates at a slower speed than the fan speed setting. •...
SPECIAL REMARKS ‘‘DRY’’ ( ) Operation How it works? • Once the room temperature reaches the level that was set, the unit’s operation frequency is changed automatically. • During DRY operation, the fan speed automatically runs at lower speed for providing a comfortable breeze.
SETTING THE TIMER In the descriptions below, the following settings are used for the temperature and NOTE time indicator selector button on the bottom front section of the remote controller. • Temperature: °F • Time: AM, PM 1. How to set the present (Example) To set to 10:30 pm.
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SETTING THE TIMER (CONTINUED) 3. How to set the ON time (Example) To start operation at 7:10 am. Operation Indication 1. Press the ON TIME setting The timer indication is displayed, button once. and the present ON time is shown. 2.
USING THE 1-HOUR OFF TIMER 1. 1-Hour OFF Timer This function causes the unit to operate for one hour and then stop, regardless of whether the unit is on or off when this button is pressed. indicator in the display indicates that this function is operating. Setting procedure: Regardless of whether the unit is operating or stopped, press the 1 HR.
ADJUSTING THE AIRFLOW DIRECTION 1. Horizontal The horizontal airflow can be adjusted by moving the vertical vanes with your hands to the left or right. When the humidity is high, the vertical vanes should be in the front CAUTION position during the cooling or dehumidifying operation. If the vertical vanes are positioned all of the way to the right or left, condensation may begin to form around the air vent and drip down.
OPERATION WITHOUT THE REMOTE CONTROLLER INDOOR UNIT If you have lost the remote controller or it has trouble, follow the steps below. When the air conditioner is not running Each time the OPERATION button is pressed, the operation mode changes cyclically.
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CARE AND CLEANING (CONTINUED) Filter The filter behind the air intake grille should be checked and cleaned at least once every two weeks. How to remove the filter 1. Grasp both ends of the air Air intake grille intake grille, and remove it by opening towards the front and pulling towards you.
CARE AND CLEANING (CONTINUED) Cleaning the main unit and • Wipe clean using a soft, dry cloth. Remote Controller • To remove stubborn dirt, moisten a cloth in warm water no hotter than 104 °F, wring thoroughly, and then wipe. •...
2. Consult your dealer. OPERATING RANGE The air conditioner is operable within the temperature ranges as listed below: For Cooling Only Models : CU-KS18NKU, CU-KS24NKU Temperature Indoor air temperature Outdoor air temperature COOLING Max.
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1-3. Optional Copper Tubing Kit Model No. 1-4. Type of Copper Tube and Insulation Material 1-5. Additional Materials Required for Installation Indoor Unit Outdoor Unit CS-KS18NKU CU-KS18NKU INSTALLATION SITE SELECTION ....5 2-1. Indoor Unit CU-KS18NKUA 2-2. Outdoor Unit CS-KS24NKU CU-KS24NKU 2-3.
IMPORTANT! When Transporting Please Read Before Starting Be careful when picking up and moving the indoor and out- door units. Get a partner to help, and bend your knees when This air conditioning system meets strict safety and operating lifting to reduce strain on your back. Sharp edges or thin alu- standards.
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Others the flare and union tubes before connecting them, CAUTION then tighten the nut with a torque wrench for a leak- free connection. the refrigeration system. Escaped refrigerant gas, on contact with fire or heat, can produce dangerously or re-installation, and while repairing refrigeration parts. toxic gas.
1. General 6. Sabre saw or key hole saw This booklet briefly outlines where and how to install the 7. Hacksaw air conditioning system. Please read over the entire set 8. Core bits of instructions for the indoor and outdoor units and make 9.
1-5. Additional Materials Required for Installation Indoor unit Refrigeration (armored) tape Insulated staples or clamps for connecting wire (See local codes.) Putty Refrigeration lubricant Clamps or saddles to secure refrigerant tubing Drain hose 2. Installation Site Selection Outside drainage 2-1. Indoor Unit Fig.
(level concrete pad, concrete block, 4" 1'4" (10 40 cm) or 6" 1'4" (15 40 cm) beams Obstacle above (CU-KS18NKU) or equal), a minimum of 4" (10 cm) or 6" (15 cm) above (CU-KS18NKUA) ground level to reduce humidity and protect the unit Min.
2-3. Baffle Plate for the Outdoor Unit (CU-KSxxNKUA models only) Air intake baffle NOTE Wind It is recommended to use baffle plates for models CU-KS18NKUA and CU-KS24NKUA. The baffle plates Front are not normally required for the other models. When the outdoor unit is installed in a position exposed to strong wind (such as seasonal winds with low air tem- Back Wind...
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(1) Recommended dimensions of the baffle plates Air Intake Baffle Air Discharge Baffle 2- 15/64" 6 mm) 1/4" 6.5 mm) 1/4" 6.5 mm) Fig. 5g Fig. 5h For Air Intake Dimensions Model (inch) 24-13/32 25/32 1-25/32 22-1/4 9-1/4 9-1/4 25/64 25/32 19/32 23-1/8...
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(3) Installation procedure 1. Air Intake Baffle 2. Air Discharge Baffle 1. Remove the panels front, top, side L and R from the (1) Left side unit and drill 4 holes of ø1/4 inch (6.5 mm) at the 1. Remove the top panel from the unit. prescribed positions.
3. How to Install the Indoor Unit 3-1. Remove the Rear Panel from the Unit (1) Remove and discard the set screw on the rear panel. (Fig. 6) (2) Press the 2 marks on the frame cover and disen- gage the stationary tabs from the frame. (Fig. 7) Set screw only for transportation (3) Remove the rear panel.
(4) Using a sabre saw, key hole saw or hole-cutting drill NOTE attachment, cut a hole in the wall. See Table 4 and Hole should be made at a slight downward slant to the Fig. 10. outdoor side. Table 4 Indoor Outdoor side...
Grille Air intake grille 3-4. Remove the Grille to Install the Indoor Unit Basically, these models can be installed and wired with- out removing the grille. If access to any internal part is needed, follow the steps as given below. How to remove the grille (1) Grasp both ends of the air intake grille, and remove Fig.
3-5. Shape the Indoor Side Tubing (1) Arrangement of tubing by direction Frame a) Right or left tubing Cut out the corner of the right/left frame with a hacksaw or the like. (Figs. 20 and 21) Left tubing outlet b) Right-rear or left-rear tubing In this case, the corner of the frame need not be cut.
3-8. Wiring Instructions for Inter-unit Connections Rear (1) Insert the inter-unit wiring (according to local codes) Wall panel into the through-the-wall PVC pipe. Run the wiring Plastic toward the indoor side allowing approx. 10" (25 cm) cover to extend from the wall face. (Fig. 24) (2) Grasp both ends of the air intake grille, and remove Wiring it by opening towards the front and pulling towards...
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Loose wiring may cause the WARNING terminal to overheat or result in unit malfunction. A fire hazard may also exist. There- fore, be sure all wiring is tightly connected. When connecting each power wire to the corresponding terminal, follow the instructions “How to connect wiring to the terminal”...
3-9. Mounting (1) To install the indoor unit, mount the indoor unit onto the 2 tabs on the upper part of the rear plate. (2) Hold down the air discharge outlet and press the lower part of the indoor unit until it clicks to securely fasten to the 2 tabs on the lower part of the rear plate.
Left-side tubing Rear panel (1) Lead the tubing and drain hose through the wall, Hole in wall allowing sufficient length for connection. Then bend the tubing using a tube bender to make the attach- ment. (Fig. 38) Wide tube Bent part (2) Switch the drain hose and drain cap.
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To unmount indoor unit Press the 2 marks on the lower part of the indoor unit and unlatch the tabs. Then lift the indoor unit and unmount. (Fig. 42) 3-10. Drain Hose a) The drain hose should be slanted downward to the outdoors.
4. How to Install the Outdoor Unit First refer to Section 2. Installation Site Selection. 4-1. Wiring Instructions for the Outdoor Unit Lock nut Regulations on wire size differ from locality to locality. For Cabinet field wiring requirements, please refer to your local elec- trical codes.
5. Refrigerant Tubing Deburring Before After 5-1. Use of the Flaring Method Many of the conventional split system air conditioners employ the flaring method to connect refrigerant tubes which run between indoor and outdoor units. In this method, the copper tubes are flared at each end and connected with flare nuts.
5-4. Connecting Tubing between Indoor and Torque wrench Outdoor Units a) Tightly connect the indoor side refrigerant tubing exten- ded from the wall with the outdoor side tubing. (Fig. 52) Spanner Indoor unit b) To fasten the flare nuts, apply specified torque as: Table 6 Outdoor unit Tube Dia.
6. Air Purging Indoor unit Air and moisture remaining in the refrigerant system have undesirable effects as indicated below. Therefore, they must be purged completely. pressure in the system rises operating current rises cooling (or heating) efficiency drops Outdoor unit moisture in the air may freeze and block capillary tubing water may lead to corrosion of parts in the refrigerant system...
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(5) With the vacuum pump still running, close the “Lo” knob of the manifold valve. Then stop the vacuum pump. 90° (1/4 turn) Narrow tube (6) With the hex wrench, turn the valve stem on the narrow tube service valve counter-clockwise by Hex wrench 90 degrees (1/4 turn) for 10 seconds, and then turn the stem clockwise to close it again.
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How to Test Run the Air Conditioner After turning on the power of the air conditioner, use the remote controller and follow the steps below to conduct the test run. (1) Set the remote controller in Test Run mode. (Fig. 59a) a)Press and hold the QUIET button and the 1HR.
Basic Functions of the Service Valves The basic functions of the service valves are given in Table 8 below. Table 8 Narrow Tube Service Wide Tube Service Action Valve (2-Way) Valve (3-Way) O-ring Valve cap CLOSED Stem Shipping Fully OPEN Operating and test running the air conditioner...
Service Valve Connections a) Temporary connection: Screw in 3 – 5 turns by hand. (Fig. 60c) b) To fasten the flare nuts, apply specified torque as Table 9 and Fig. 60d. Torque wrench Table 9 Fig. 60c Fig. 60d Tube Dia. Tightening Torque Be sure to tighten the 1/4"...
8. Address Switch 8-1. Address Setting of the Remote Controller The address can be set in order to prevent interference between remote controllers when 2 indoor units are installed near each other. The address is normally set to “A.” To set a different address, it is necessary to change the address on the second remote controller.