General information of Outdoor Units Model name Dimension (mm) Compressor KSM135D23UFZ K2OC-18HFN32 800x333x554 KTF235D22UMT K3OE-27HFN32 845x363x702 KTF310D43UMT K4OB-36HFN32 946x410x810 KTF310D43UMT K5OD-42HFN32 946x410x810...
Features Outdoor unit Power relay control Low noise air flow system Hydrophilic aluminum fin the heating efficiency at operation mode. The hydrophilic fin can improve 4 way valve control It is only operated in the heating operation mode except defrosting operation. Anti-rust cabinet Valve protection cover It protects the valves and prevents water from dripping.
Refrigeration Cycle Diagram Refrigeration circuit drawing of inverter 1 drive 2 type I N D O O R O U T D O O R E X V A C A P I L L A R Y A L I Q U I D V A L V E A C H E C K V A L V E E X V B C A P I L L A R Y B L I Q U I D V A L V E B...
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4.3 Refrigeration circuit drawing of inverter 1 drive 4 type I N D O O R O U T D O O R E X V A C A P IL L A R Y A L IQ U ID V A L V E A E X V B C A P IL L A R Y B L IQ U ID V A L V E B C H E C K V A L V E...
Indoor units combination Indoor unit combination for K2OC-18HFN32 One unit Two unit 9+12 7+12 9+18 7+18 12+12 Indoor unit combination for K3OE-27HFN8-Q One unit Two unit Three unit 12+1 7+7+7 7+9+9 7+12+1 9+12+1 9+12 18+1 7+7+9 7+9+12 9+9+9 9+12+1 7+12...
Sound Levels Outdoor Unit Microphone 1.0m Note: H= 0.5 × height of outdoor unit Model Noise Power dB(A) Noise level dB(A) K2OC-18HFN32 K3OE-27HFN32 K4OB-36HFN32 K5OD-42HFN32...
Installation Details 8.1 Wrench torque sheet for installation Outside diameter Torque Additional tightening torque N.cm N.cm Ф6.35 1500(153kgf.cm) 1600(163kgf.cm) Ф9.52 2500(255kgf.cm) 2600(265kgf.cm) Ф12.7 3500(357kgf.cm) 3600(367kgf.cm) 8.2 Connecting the cables The power cord of connect should be selected according to the following specifications sheet. Nominal cross-sectional area (mm²) Rated current of appliance >3 and ≤6...
● When refrigerant pipe diameter is different from that of outdoor unit union (for 18K&24K indoor unit), additional transfer connector needs to be used on outdoor unit union. Indoor unit Extension pipe diameter (mm/inch) Model Pipe diameter (mm/inch) Liquid 6.35(1/4) Liquid 6.35(1/4) 7K9K12K...
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(Indoor unit) (Outdoor unit) (Liquid side) Two-way valve Close (Gas side) Three-way valve Close Manifold valve Compound meter Pressure gauge -0.1MPa Handle Lo Handle Hi Charge hose Charge hose Vacuum pump Vacuum pump 1) Completely tighten the flare nuts of the indoor and outdoor units, confirm that both the 2-way and 3-way valves are set to the closed position.
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2. Adding the refrigerant if the pipe length >5m Electronic scale Procedure: 1). Connect the charge hose to the charging cylinder, open the 2-way valve and the 3-way valve. Connect the charge hose which you disconnected from the vacuum pump to the valve at the bottom of the cylinder.
8.5 Adding the refrigerant after running the system for many years Electronic scale Procedure: 1). Connect the charge hose to the 3-way service port, open the 2-way valve and the 3-way valve. Connect the charge hose to the valve at the bottom of the cylinder. If the refrigerant is R410A, make the cylinder bottom up to ensure liquid charge.
8.6 Re-installation while the indoor unit need to be repaired 1. Collecting the refrigerant into the outdoor unit Procedure 1). Confirm that both the 2-way and 3-way valves are set to the opened position Remove the valve stem caps and confirm that the valve stems are in the opened position. Be sure to use a hexagonal wrench to operate the valve stems.
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2. Air purging with vacuum pump (Indoor unit) (Outdoor unit) (Liquid side) Two-way valve Close (Gas side) Three-way valve Close Manifold valve Compound meter Pressure gauge -0.1MPa Handle Lo Handle Hi Charge hose Charge hose Vacuum pump Vacuum pump Procedure: 1) Completely tighten the flare nuts of the indoor and outdoor units, confirm that both the 2-way and 3-way valves are set to the closed position.
8.7 Re-installation while the outdoor unit need to be repaired 1. Evacuation for the whole system Procedure: 1). Confirm that both the 2-way and 3-way valves are set to the opened position. 2). Connect the vacuum pump to 3-way valve’s service port. 3).
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2. Refrigerant charging Procedure: 1). Connect the charge hose to the charging cylinder, open the 2-way valve and the 3-way valve Connect the charge hose which you disconnected from the vacuum pump to the valve at the bottom of the cylinder.
Electronic control function 9.1 Abbreviation T1: Indoor ambient temperature T2: Coil temperature of indoor heat exchanger middle. T2B: Coil temperature of indoor heat exchanger outlet(This sensor is located in outdoor unit) T3: Coil temperature of outdoor heat exchanger T4: Outdoor ambient temperature T5: Compressor discharge temperature Ts: Setting temperature 9.2 Electric control working environment.
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9.4 Outdoor unit point check function A check switch is included on the outdoor PCB. Push SW1 to check the unit's status while running. The digital display shows the following codes each time the SW1 is pushed. Display Remark Number Presses Normal display Displays running frequency, running state, or malfunction code...
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99 ℃, the digital display shows single and double digits. For example, if the digital display shows “0.5", the compressor discharge temperature is 105 ℃. AD value of current The display value is a hex number. For example, the digital display tube shows “Cd”, it means AD value is AD value of voltage 205.
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V O L T A G E N o li m it V O L T _ L T M _ F R E Q 1 _ A D D V O L T _ L T M _ F R E Q 2 _ A D D Note: if the low voltage protection occurs and not resumes within 3 minutes, it will keep the protection always after restart the machine.
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O f f D e c r e a s e H o ld R e s u m e 9.5.7 Outdoor unit anti-freezing protection When T2<4℃ for 250 seconds or T2<0℃, the indoor unit capacity demand will be zero and resume to normal when T2>8℃...
10. Troubleshooting Indoor unit error code explanation: 10.1 For all type indor , Four-way cassette type (compact): Operation Lamp Malfunction Timer Lamp Error Code (flashes) Indoor EEPROM malfunction Communication malfunction between indoor and outdoor units Indoor fan speed has been out of control Open or short circuit of T1 temperature sensor Open or short circuit of T2 temperature sensor Water level alarm...
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For 2 unit type: Malfunction Error Code Indoor unit EEPROM parameter error E0/EA Indoor / outdoor units communication error Indoor fan speed is operating outside of the normal range Indoor room temperature sensor T1 open circuit or short circuit Evaporator coil temperature sensor T2 open circuit or short circuit Communication error between the indoor PCB and display board Overload current protection Outdoor ambient temperature sensor T4 open circuit or short circuit...
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Outdoor unit error code explanation: 10.2 Display LED STATUS Outdoor EEPROM malfunction Indoor / outdoor units communication error Communication malfunction between IPM board and outdoor main board Open or short circuit of outdoor unit temperature sensor(T3,T4.T5) Voltage protection PFC module protection Outdoor fan speed has been out of control No A Indoor unit coil outlet temperature sensor or connector of sensor is defective No B Indoor unit coil outlet temperature sensor or connector of sensor is defective...
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Trouble shooting 10.3 10.3.1 For the indoor unit 10.3.1.1 Indoor EEPROM malfunction Power off, then restart the unit 2 minutes later Replace the indoor main PCB EEPROM: An electrically erasable programmable read-only memory whose contents can be erased and reprogrammed using a pulsed voltage.
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10.3.1.2 Indoor / outdoor units communication error Indoor / outdoor units communication error Start: Power off , then Power on the A/C by the Breaker. (reconnect the power wire). Is it still displaying the error code? Check wiring on the outdoor and indoor terminal follow the wiring diagram.
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Pic 1: check the voltage of N to S (Vs), is it moving alternately between positive value and negative value? Pic 2:IPM or outdoor main PCB Pic 2: IPM or outdoor main PCB Power, Self-Check Operating...
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PIC3 :Main board LED when power on and unit standby. PIC 4: check point button, Press 1 time for check how many indoor units are connected...
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10.3.1.3 Indoor fan speed has been out of control Power off, then restart the uni 2 mi nutes l ater. Is i t sti ng the error code? The uniit operates normallly Shut off the power suppl rotate the fan by hand. Does i Fiind out the cause and have iit sollved.
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DC motor voltage input and output For split type: Color Signal Voltage Vs/Vm 280V~380V Black White 14-17.5V Yellow 0~5.6V Blue 14-17.5V For other types: Color Signal Voltage Vs/Vm 192V~380V Black White 13.5-16.5V Yellow 0~6.5V Blue 13.5-16.5V...
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10.3.1.4 Open or short circuit of temperature sensor. Check the connecti between temperature Correct the connectiions sensor and PCB. Are the good? connecti Measure the resi stance val ue of the sensor vi a Appendi Repl ace the sensor. Is iit normall Repl ace the i ndoor PCB...
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10.3.1.6 E6(PFC module protection) PFC module protection Check whether the connecting line between Connect it tightly, check main board and the PFC normal or not module(IPM module) is connected tightly Check whether the voltage range of P-N on IPM module Replace the outdoor main board is normal? DC277-356V for 18-27KBtu/h;...
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10.3.1.8 Inverter compressor drive malfunction(P4) The trouble shooting is same with IPM module protection. 10.3.3 For the outdoor unit 10.3.3.1 Outdoor EEPROM malfunction(ODU E0) Power off, then restart the unit 2 minutes later Repl ace the outdoor mai n PCB EEPROM: An electrically erasable programmable read-only memory whose contents can be erased and reprogrammed using a pulsed voltage.
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10.3.3.2 Communication malfunction between IPM board and outdoor main board(ODU E3) E3 display Communication malfunction between IPM board and outdoor main board Is there at least one LED in the IPM board light? Check the signal wire between the IPM board and the main board, is it connected good? Reconnect and retry.
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10.3.3.3 Voltage protection(ODU E5) Voltage protection Check the voltage of outdoor unit power supply, whether the voltage Check the power supply between L(L1) and N (L2) is about 220~240VAC Check whether the voltage of IPM board P and N is normal? DC277-356V for 18-27KBtu/h;...
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10.3.3.4 Outdoor fan speed has been out of control (E8) Power off, then restart the uni nutes l ater. Is i t sti ng the The uniit operates normallly error code? Shut off the power suppl Fiind out the cause and rotate the fan by hand.
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10.3.3.5 High pressure protection (ODU P1)(For K4OB-36HFN32, K5OD-42HFN32) High pressure protection Whether the wi between the hi Connect i t wel pressure swi tch and n control board i connected wel correctl Whether the gh pressure protector s broken Method: Di sconnect Measure t Repl...
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10.3.3.6 Low pressure protection (ODU P2) (For K4OB-36HFN32, K5OD-42HFN32) Low pressure protection Whether the wi between the l ow pressure Connect i t wel protector and mai n control board i s connected wel correctl Whether the l pressure protector s broken Method: Di sconnect the pl...
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10.3.3.7 Current protection of compressor (ODU P3) Current protection of compressor Judge 1: Check whether the input current of the power supply wire is higher than max protection current value Check whether the refrigerant system is ok Judge 2: Check whether the outdoor ambient Stop the unit temperature is higher than...
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10.3.3.8 Temperature protection of compressor discharge (ODU P4) Temperature protection of compressor discharge Check whether the Stop l eaki ng and add refri gerant compressor di scharge temp. i r r i t t i s s l more than 115°C ? Check whether connecti...
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10.3.3.9 High temperature protection of condenser (ODU P5) When outdoor pipe temperature is more than 65°C, the unit will stop, and unit runs again when outdoor pipe temperature less than 52°C. Check the Correct the connecti connecti gh temperature protecti on of between condenser...
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10.3.3.10 IPM module protection (ODU P6) IPM module protection Check whether the voltage range Check whether the input Regulate it to correct, then of P-N on IPM module is normal? power supply is correct? check whether the system DC277-356V for 18-28KBtu/h; can work normally? 208-230V, 1N, 60Hz DC277-410V for 36-42KBtu/h...
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10.3.3.11 The cooling operation or heating operation does not operate. Potential causes ● Faulty 4-way valve Check of 4-way, please refer to part 4 in 10.4 Trouble Criterion Of Main Parts. 10.3.3.12 When cooling, heat exchanger of non-operating indoor unit frosts. When heating, non-operating indoor unit get warm.
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10.4 Main parts check 1. Temperature sensor checking Disconnect the temperature sensor from PCB, measure the resistance value with a tester. Temperature Sensors. Room temperature(T1) sensor, Indoor coil temperature(T2) sensor, Outdoor coil temperature(T3) sensor, Outdoor ambient temperature(T4) sensor, Compressor discharge temperature(T5) sensor. Measure the resistance value of each winding by using the multi-meter.
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Appendix 1 Temperature Sensor Resistance Value Table for T1,T2,T3,T4,T2B (℃--K) K Ohm K Ohm K Ohm K Ohm ℃ ℃ ℃ ℃ 115.266 12.6431 2.35774 0.62973 108.146 12.0561 2.27249 0.61148 101.517 11.5000 2.19073 0.59386 96.3423 10.9731 2.11241 0.57683 89.5865 10.4736 2.03732 0.56038 84.2190...
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Appendix 2 Temperature Sensor Resistance Value Table for T5 (℃--K) K Ohm K Ohm K Ohm K Ohm ℃ ℃ ℃ ℃ 542.7 68.66 13.59 3.702 511.9 65.62 13.11 3.595 62.73 12.65 3.492 455.9 59.98 12.21 3.392 430.5 57.37 11.79 3.296 406.7 54.89...
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2.Compressor checking Measure the resistance value of each winding by using the tester. Position Resistance Value KSM135D23UFZ KTF235D22UMT KTF310D43UMT Blue - Red 1.72Ω(20℃) 0.75Ω(20℃) 0.65Ω(20℃)
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3. IPM continuity check Turn off the power, let the large capacity electrolytic capacitors discharge completely, and dismount the IPM. Use a digital tester to measure the resistance between P and UVWN; UVW and N. Digital tester Normal resistance value Digital tester Normal resistance value (+)Red...
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5.EXV check Disconnect the connectors. Red Brown Blue Orange Yellow White Resistance to EXV coil Color of lead wire Normal Value Red- Blue About 50Ω Red - Yellow Brown-Orange...
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