Troubleshooting & Reference

Error Code Descriptions Description of Error Codes - 9, 12 MBH code malfunction Error Display Repair Method 1 Storage slug (EEPROM) 2 Indoor PCB malfunction 3 Anti-freezing protection Dual 8 Display EE EE E2 Heating : pause 3s and blink 15 times Heating : pause 3s and blink 15 times Running : pause 3s and blink 2 times 4 System overload H4 Heating : pause 3s and blink 4 times 5 No indoor motor feedback 6 Indoor pipe (tube) temperature sensor malfunction 7 Internal ambient temperature sensor malfunction 8 Zero passage abnormal 9 Compressor overload H6 F2 F1 UF H3 Running : pause 3s and blink 11 times Cooling : pause 3s and blink 2 times Cooling : pause 3s and blink 1 time Heating and Cooling : blinks 7 times at the same time Heating : pause 3s and blink 3 times Replace indoor main board Replace indoor main board Outdoor ambient temperature is too low System Abnormal: Check evaporator and condenser coils for dirty or blocked condition Check indoor fan motor for proper mounting. Inspect for obstructions blocking fan rotation. Check Wiring & PCB plug. Check that sensor is properly positioned and securely attached. Measure the resistance of the sensor with an ohmmeter Check that sensor is properly positioned and securely attached Measure the resistance of the sensor with an ohmmeter Replace indoor main board Inspect overload wire connection

Error Code Descriptions Description of Error Codes - 9, 12 MBH code malfunction Error Display Repair Method Dual 8 Display 10 Startup failure LC Heating : pause 3s and blink 11 times 11 No outdoor motor feedback 12 Over-current protection 13 Defective 4-way valve conversion 14 Compressor phase current detection malfunction UH E5 U7 U1 Heating and Cooling : blinks 8 times at the same time Running : pause 3s and blink 5 times Cooling : pause 3s and blink 20 times Heating : pause 3s and blink 13 times 15 Sync failure H7 Heating : pause 3s and blink 7 times 16 Indoor and outdoor unit are not communicating 17 Outdoor ambient temperature sensor malfunction U5 F3 Cooling : pause 3s and blink 13 times Cooling : pause 3s and blink 3 times Check the resistance of the compressor and ground to see if it is normal, the outdoor board may need to be replaced Check feedback wiring and connectors. This problem may happen when an outdoor DC electromotor is used Check AC supply voltage to system Replace 4-way valve Replace outdoor main board Check the resistance of the compressor and ground to see if it is normal. If the compressor is normal, the outdoor board may need to be replaced. Replace outdoor main board Check that sensor is properly positioned and securely attached. Measure the resistance of the sensor with an ohmmeter

Error Code Descriptions Description of Error Codes - 9, 12 MBH code malfunction Error Display Repair Method 18 Compressor discharge protection 19 Broken or short circuit of the outdoor discharge temperature sensor 20 Broken or short circuit of the outdoor condenser temperature sensor 21 Carbon fin overheating Dual 8 Display E4 F5 F4 P8 Running : pause 3s and blink 4 times Cooling : pause 3s and blink 5 times Cooling : pause 3s and blink 18 times Heating : pause 3s and blink 19 times 22 DC over-current UU Heating and Cooling : blink 11 times at the same time 23 Heat sink temperature sensor malfunction 24 Lack of freon or block connection 25 DC input voltage is too high P7 F0 PH Heating : pause 3s and blink 18 times Cooling : pause 3s and blink 10 times Cooling : pause 3s and blink 11 times Check that sensor is properly positioned and securely attached. Measure the resistance of the sensor with an ohmmeter Check that sensor is properly positioned and securely attached. Measure the resistance of the sensor with an ohmmeter Check that sensor is properly positioned and securely attached. Measure the resistance of the sensor with an ohmmeter Outdoor ambient temperature may be too high or the radiator is mounted incorrectly Replace outdoor main board Check for correct AC power supply voltage

Error Code Descriptions Description of Error Codes - 9, 12 MBH code malfunction Error Display Repair Method 26 DC input voltage is too low 27 Communication malfunction 28 Setting error, indoor and outdoor unit are not matched Dual 8 Display PL E6 UA Heating : pause 3s and blink 21 times Running : pause 3s and blink 6 times Heating and Cooling : blink 12 times at the same time Check for correct AC power supply voltage Check outdoor connecting wire connection Outdoor unit is not matched with indoor unit

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have System protection from high pressure Anti-freezing protection Double 8 Code Display E1 E2 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Off 3s Blinks 1 time Off 3s Blinks 2 times Cooling Heating 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: compressor will stop running while indoor fan motor keeps running During heating mode: all stop running During cooling and dehumidifying mode: compressor and outdoor fan motor will stop running while indoor fan motor keeps running Possible Malfunction Problems 1. Too much refrigerant 2. Poor heat transfer caused by dirty heat exchanger and/or poor unit heating 3. Ambient temperature is too high 1. Poor indoor unit air circulation 2. Irregular indoor fan motor speed 3. Dirty evaporator

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Compressor air exhaust temperature protection AC overload protection Double 8 Code Display E4 E5 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Off 3s Blinks 4 times Off 3s Blinks 5 times Cooling Heating 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: compressor and outdoor fan motor will stop running while indoor fan motor keeps running During heating mode: all stop running During cooling and dehumidifying mode: compressor and outdoor fan motor will stop running while indoor fan motor keeps running During heating mode: all stop running Possible Malfunction Problems 1. Please refer to air exhaust protection overload troubleshooting 1. Power supply voltage c flut uat ions 2. Power supply voltage too low

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Indoor and outdoor units are not communicating High temperature protection Double 8 Code Display E6 E8 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Off 3s Blinks 6 times Off 3s Blinks 8 times Cooling Heating 3 types of display) Off On Blinks D40 D41 D42 D43 System Status Cooling mode: compressor will stop while indoor fan motor keeps running During heating mode: all stop running Cooling mode: compressor will stop while indoor fan motor will operate During heating mode: all will stop running Possible Malfunction Problems 1. Please refer to troubleshooting 1. Please refer to troubleshooting

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Indoor fan motor does not operate Jumper cap malfunction protection Double 8 Code Display H6 C5 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Off 3s Blinks 11 times Off 3s Blinks 15 times Cooling Heating 3 types of display) Off On Blinks D40 D41 D42 D43 System Status Entire unit will stop running Entire unit will stop running Possible Malfunction Problems 1. Poor connection at PGF (PG Motor Feedback) on the board 2. AP1 indoor control board malfunction 3. Indoor motor M1 malfunction 1. AP1 indoor control board jump cap is poorly connected 2. Please reinsert or replace the jump cap

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Indoor ambient sensor is open/ short circuited Indoor evaporator sensor is open/ short circuited Double 8 Code Display F1 F2 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Off 3s Blinks 1 time Off 3s Blinks 2 times Heating 3 types of display) Off On Blinks D40 D41 D42 D43 System Status Cooling mode, humidifying mode: indoor fan motor keeps running while other overloads will stop During heating mode: entire unit will stop running Cooling mode, humidifying mode: indoor fan motor keeps running while other overload will stop During heating mode: entire unit will stop Possible Malfunction Problems 1. Room temperature sensor is not properly connected on the AP1 control panel 2. Room temperature sensor is damaged 1. Tube temperature sensor is not properly connected on the control panel AP1 2. Tube temperature sensor is damaged

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Outdoor ambient sensor is open/short circuited Outdoor condenser sensor is open/ short circuited Double 8 Code Display F3 F4 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Off 3s Blinks 3 times Off 3s Blinks 18 times Heating 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: compressor will stop while indoor fan motor will work During heating mode: entire unit will stop During cooling and dehumidifying mode: compressor will stop while indoor fan motor will work During heating mode: entire unit will stop Possible Malfunction Problems 1. Outdoor ambient temperature sensor is not properly connected or damaged 2. Measure sensor resistance m and confir that it is correct. 1. Outdoor tube temperature sensor is not connected properly or damaged 2. Measure sensor resistance m and confir that it is correct.

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Outdoor air exhaust sensor is open/short circuited Limit / decrease frequency from overload Decrease frequency from over current Double 8 Code Display F5 F6 F8 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Off 3s Blinks 3 times Off 3s Blinks 6 times Off 3s Blinks 8 times Heating 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: after running for 3 minutes, compressor will stop running while indoor fan motor will start to run During heating mode: after 3 minutes all will stop running Normal load operation while the compressor operation frequency is decreased Normal load operation while the compressor operation frequency is decreased Possible Malfunction Problems 1. Exhaust temperature sensor is not connected properly or damaged 2. Measure sensor resistance m and confir that it is correct. 3. Sensor head is not properly inserted into the copper tube 1. Please refer to troubleshooting 1. Input power supply too low 2. System voltage too high, overload too much

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Decrease frequency from air discharge being too high Double 8 Code Display F9 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Off 3s Blinks 9 times Heating 3 types of display) Off On Blinks D40 D41 D42 D43 System Status Normal load operation while the compressor operation frequency is decreased Possible Malfunction Problems 1. Overload too much 2. Ambient temperature too high 3. Refrigerant is short 4. Electronic expansion valve malfunction

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have DC bus-bar voltage too high Double 8 Code Display PH Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Off 3s Blinks 11 times Heating 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: compressor stops running, fan motor runs During heating mode: all will stop Possible Malfunction Problems 1. Test wire terminal L and N position. If higher than 265 VAC, disconnect power supply and correct input voltage. If input voltage is normal, test the voltage of electrolytic capacitor on API after turning on the units. There may be some problem and replace the API if the electrolytic capacitor voltage range at 200 280V.

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Complete unit current testing malfunction Over current protection for compressor phase current Defrosting Double 8 Code Display U5 P5 H1 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Off 3s Blinks 13 times Off 3s Blinks 15 times Heating Off 3s Blinks 1 time 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running. During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running. During heating mode: compressor running, indoor / outdoor fan motor stop running Possible Malfunction Problems 1. Malfunction on API circuit. Replace the outdoor unit API. 1. Please refer to troubleshooting (IPM protection, compressor step loss, compressor over current protection) 1. Normal operation

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Electrostatic dedusting protection Compressor overload protection System overload Double 8 Code Display H2 H3 H4 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Heating Off 3s Blinks 2 times Off 3s Blinks 3 times Off 3s Blinks 4 times 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running During cooling and drying mode: compressor will stop running, indoor fan runs. During heating mode: all will stop running. Possible Malfunction Problems 1. Wire terminal OVC-COMP loose or circuit problem, resistance of SAT should be lower than 1 ohm. 2. Please refer to trouble shooting (exhaust / overload protection) 1. Refer to malfunction analysis (overload, high temperature resistant)

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have IPM protection PFC protection Double 8 Code Display H5 HC Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Heating Off 3s Blinks 5 times Off 3s Blinks 6 times 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and drying mode: compressor will stop running, indoor fan runs. During heating mode: all will stop running. During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running Possible Malfunction Problems 1. Refer to malfunction analysis (IPM protection, compressor step loss, compressor over current protection) 1. Please refer to troubleshooting

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Compressor is out of sync Frequency decrease during heating mode from high temperature protection Double 8 Code Display H7 H0 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Heating Off 3s Blinks 7 times Off 3s Blinks 10 times 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running Overload normal, compressor running, frequency declines Possible Malfunction Problems 1. Please refer to troubleshooting 1. Please refer to troubleshooting

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Start-up failure Compressor phase current detection circuit malfunction EEPROM malfunction Double 8 Code Display LC U1 EE Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Heating Off 3s Blinks 11 times Off 3s Blinks 13 times Off 3s Blinks 15 times 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. Heating: all will stop running. During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running Possible Malfunction Problems 1. Please refer to troubleshooting 1. Replace outdoor control board AP1 1. Replace outdoor control board AP1

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Capacitor charging malfunction Module temperature sensor circuit malfunction Double 8 Code Display PU P7 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Heating Off 3s Blinks 17 times Off 3s Blinks 18 times 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. Heating: all will stop running. During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running. Possible Malfunction Problems 1. Please refer to part 3 capacitor charging fault of troubleshooting 1. Replace outdoor control board AP1

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Module high temperature protection DC busbar voltage dropping Double 8 Code Display P8 U3 Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Heating Off 3s Blinks 19 times Off 3s Blinks 20 times 3 types of display) Off On Blinks D40 D41 D42 D43 System Status During cooling and humidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running. During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running Possible Malfunction Problems 1. Check the temperature of IPM to see whether it is too high. Check IPM heat sink to see whether it is too dirty. If so, replace outdoor board API. 1. Power voltage not stable

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have Low DC busbar voltage protection Limit / decrease frequency from high IPM module temperature Double 8 Code Display PL Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Heating Off 3s Blinks 21 times 3 types of display) Off On Blinks D40 D41 D42 D43 EU System Status During cooling and dehumidifying mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running. Overload normal, compressor running with declining frequencies Possible Malfunction Problems 1. Check input voltage. If the voltage is lower than 150 VAC, restart the system when the power supply is normal. 2. Check reactor L connection. 1.Disconnect power for 20 minutes, discharge capacitor. Check outdoor unit AP1 IPM module for properly installed and secured heatsink. Correct or replace AP1 control board as necessary.

Error Code Descriptions Description of Error Codes - 18, 24 MBH Malfunction Indoor Unit Display Outdoor Unit Display (s have abnormal 4-way valve operation Outdoor unit zero-cross detecting error anti-freezing limit / frequency decrease Double 8 Code Display Indicator Display ( blinks 0.5s - ON / 0.5s - OFF) Running Cooling Heating 3 types of display) Off On Blinks D40 D41 D42 D43 U7 U9 FH System Status During heating mode: all will stop running During cooling mode: compressor stops running, indoor fan motor runs. During heating mode: all will stop running All loads work normally, running frequency limit or decrease Possible Malfunction Problems 1. Power supply voltage is lower than 175 VAC. 2. 4-way valve wire terminal loose or wire harness damaged 3. 4-way valve damaged, replace 4-way valve. 1. Replace outdoor control board API 1. Indoor unit air circulation is poor or fan speed is too low.

Common Error Code Diagnostics F (1-5) Description Short or open circuit of the temperature sensor. Indoor Unit Outdoor Unit F1 Error Code Error code displayed for indoor ambient temperature sensor malfunction. F3 Error Code Error code displayed for outdoor ambient temperature sensor malfunction. F2 Error Code Error code displayed for indoor tube temperature sensor malfunction. F4 Error Code Error code displayed for outdoor tube temperature sensor malfunction. F5 Error Code Error code displayed for compressor discharge (exhaust) temperature sensor malfunction. Causes A: Terminal is loose. B: Sensor is pulled off or not securely mounted in position.

Common Error Code Diagnostics F (1-5) Troubleshooting Fig. 1 Fig. 1 Fig. 2 Fig. 2 *See Troubleshooting Procedures

Description Troubleshooting & Reference Common Error Code Diagnostics C5 (Jumper Cap Malfunction) C5 jumper cap malfunction is usually caused by missing assembly of previous jumper when replacing the PCB. If there is a wrong jumper, LP will show. Causes A: Jumper missing(when replacing PCB) B: Jumper is loose C: Jumper is short circuit D: The circuit of jumper on the PCB has malfunction

Common Error Code Diagnostics C5 (Jumper Cap Malfunction) Troubleshooting Fig. 1 Fig. 1

Description Troubleshooting & Reference Common Error Code Diagnostics PU Capacitor charging malfunction (outdoor unit malfunction). Causes A: Improper line voltage at L and N terminals of board B: Poor Reactor (L) wire connections C: Connection wire loose or disconnected D: Reactor (L) damaged

Common Error Code Diagnostics PU Troubleshooting Fig. 1 Fig. 1 Fig. 2 Fig. 1 Fig. 2

Description Troubleshooting & Reference Common Error Code Diagnostics LC Startup failure malfunction. Causes A: Compressor wiring incorrect B: Stop time of compressor is to little C: Compressor damage D: Overcharge

Common Error Code Diagnostics LC Troubleshooting Fig. 1 Fig. 1,2 Fig. 2

Description Troubleshooting & Reference Common Error Code Diagnostics HC PFC (correction for power factor) malfunction. Causes A: Outdoor unit Reactor (L) damaged B: PFC capacitor damaged

Common Error Code Diagnostics HC Troubleshooting Fig. 1 Fig. 1 Fig. 2 Fig. 2 Fig. 3 Fig. 3

Description Troubleshooting & Reference Common Error Code Diagnostics H3 When the controller of the outdoor unit detects that the surface temperature of the compressor is too high, the unit will stop operation and the corresponding code will be shown on the indoor unit. Causes A: Wiring of overload protector is loose B: Overload temperature sensor doesn t work C: System is abnormal, e.g. leakage, blockage, heat exchangers are dirty, working condition is bad D: Detection circuit of outdoor controller doesn t work E: Compressor has malfunction F: Low voltage

Description Troubleshooting & Reference Common Error Code Diagnostics H6 When the detected speed of the indoor fan motor is too slow for 1 minute, the H6 error code motor blockage protection will be enacted. Causes A: Motor is installed incorrectly, the terminal is loose, the fan blade is stuck, sliding bearing of the motor is off center. B: Fan speed is too low because the air outlet is blocked C: Fan capacitor is damaged D: The control circuit for the motor has abnormal output and feedback signal E: The motor is damaged or gets stuck.

Common Error Code Diagnostics H6 Troubleshooting Fig. 1 Fig. 1 Fig. 2 Fig. 2

Description Troubleshooting & Reference Common Error Code Diagnostics H5 IPM Protection (includes overcurrent, low pressure, and overheating protections of IPM module) Causes A: Wrong wiring of compressor or mismatching between electric box and compressor B: ODU controller malfunction C: System is abnormal D: Low voltage or sudden change of power supply voltage E: Starting the unit within 3 minutes of system turning off F: Pressure difference is large between high and low pressure sides G: Malfunction of compressor H: Normal protection under large load

Common Error Code Diagnostics H5 Troubleshooting WARNING! Prior to performing this test, follow the procedure on page G25 to discharge the capacitor. Failure to do so can result in electrical shock or possibly death. Check IPM Module 1. Remove power from the unit. 2. Measure the resistance between the following points using an ohmmeter. Place one lead on P, then use the other lead to check U, V, and W. Place one lead on N, then use the other lead to check U, V, and W. The values should be above 10K ohm with no big difference between readings. 3. Set the multimeter to the diode check position, then place the black lead on P, then use the red lead to check U, V, and W. 4. Place the red lead on N then use the black lead to check U, V, and W. 5. The 6 readings should all be 0.3V ~0.7V.

Common Error Code Diagnostics H5 Troubleshooting A. Check power supply and wiring. B. Check IPM Module is normal. C. Check system. D. Check compressor. Under this protection, disconnect the compressor and operate the system. If there is still a malfunction, the ODU controller has failure. If the compressor had been running for a while when the protection happened, the system is under heavy load and the current is high.

Troubleshooting Troubleshooting & Reference Common Error Code Diagnostics H5 Fig. 1 Fig. 4 Fig. 1 Fig. 2 Fig. 2 Fig. 3 Fig. 2 Fig. 5 Fig. 3 Fig. 4 Fig. 5

Description Troubleshooting & Reference Common Error Code Diagnostics H7 Compressor loss step protection, fail to synchronization. Causes A: System pressure is too high B: Voltage too low

Common Error Code Diagnostics H7 Troubleshooting Fig. 1 Fig. 2 Fig. 2 Fig. 1 Fig. 3 Fig. 3

Description Troubleshooting & Reference Common Error Code Diagnostics E4 E4 will be shown when detecting that discharge temperature of compressor is high. The compressor will stop, and will resume running after 3 minutes. Causes A: Outdoor discharge temperature sensor has malfunction B: Refrigerant leaks C: System blockage D: Malfunction of electric box E: Air in the system F: Air inlet of ODU is blocked or outdoor fan has a malfunction

Common Error Code Diagnostics E4 Troubleshooting Fig. 1 Fig. 1

Description Troubleshooting & Reference Common Error Code Diagnostics E6 E6 indicates a communication failure between the indoor and outdoor units. When the communication signal has not been received for 3 minutes, the system stops and the E6 error code is displayed. Causes A: Low voltage of the power supply B: Unmatched indoor / outdoor units C: Power cable between indoor and outdoor units D: Controller of indoor or outdoor unit malfunction E: Electronic component of indoor or outdoor unit (connecting wire, electric auxiliary heater) F: Electronic component of outdoor unit (connecting wire, electric reactor, DC motor, temp sensor, etc.)

Common Error Code Diagnostics E6 Troubleshooting

Testing Point Description To reduce the risk of shock hazard, a resistance must be placed across the + - terminals of the circuit board to drain the electrical charge from the capacitor. Place a 100Ω 20 watt resistor or the plug end of a pencil type soldering iron across the + - terminals on the circuit board for a period of 30 seconds to drain the charge from the capacitor. Verify the voltage has dropped to below 20 VDC with a voltmeter set to read DC volts. If the voltage has not dropped to below 20 VDC, reapply the resistance across the + - terminals for 30 more seconds, then check the voltage again.

Common Error Code Diagnostics Communication Circuit Diagram

Troubleshooting Air Conditioner Cannot Start Up Breaker has tripped or fuse has blown The breaker immediately trips as soon as it is turned ON. The breaker trips within minutes of turning it ON. Measure insulation resistance to ground to see if there is any resistance. The circuit or part of the air conditioner has malfunctioned. The unit heats up and breaks the insulation and eventually leads to short circuit or creepage. Measure the insulation resistance or eliminate the malfunction by narrowing the cause down one by one. If the breaker itself has malfunctioned, then replace the breaker. Air conditioner cannot start up The air conditioner does not react after it is powered (after the plug is inserted, the buzzer does not sound and the remote startup has no response) No power Power plug is loose causing a poor connection Controller fuse burnt out The transformer connection is loose, has a bad contact, or the transformer has malfunctioned Controller is defective Check power supply circuit Make sure the power plug is tightly and correctly connected Replace controller fuse Fasten the wiring; measure the output voltage of the transformer, if it is incorrect, change the transformer Replace the remote controller The remote controller does not transmit signals (after it is powered, the indoor unit buzzer will sound, unless it has malfunctioned) Remote controller has no power Remote controller malfunction Receiver has a poor connection Receiver is defective Replace remote controller batteries First press the manual switch button AUTO, if there is no response, perform checks based on the methods above. If it runs normally after pressing the button, check again whether the installation position and the connection wire of the reception head is correct. If it is correct, then replace the receiver or the remote controller. Power voltage is too low Check the voltage. If it is less than 10% of the rated voltage, check the cause, improve the power supply condition and add the stabilized voltage power supply.

Troubleshooting Poor Cooling or Heating Effect Incorrect temperature setting Correctly set the temperature Check the estimated load of cooling (heating) Refrigerant has a leak or is undercharged Vacuum after leakage detection and leakage repair. Charge arefrigerant according to correct specifict ions. Leak between high and low pressure inside compressor Replace the compressor Malfunction of w refrigerant i flo Malfunction of four-way valve Replace the four-way valve Partial tblockage of capillary Replace the capillary t Blockage of cooling system Observe the evaporator condensation and the pressure value of the high pressure manometer to see if the system is blocked and correctly being handled by the system Poor thermal insulation of connecting pipes Ensure that both thick pipe and thin pipe are insulated well. The exposed part of the connector and copper pipe must be insulated as well. Poor cooling (heating) effect Outdoor unit heat exchanger is blocked Air filer s ar e bl ocked Clean the dust accumulated on the heat exchanger Clean the air filer s Fan speed is set too slow Set the fan speed to high or medium Insufficent ai r circulation Fan turns at a low speed Damaged capacitor Damaged motor Replace the capacitor Replace the motor Outdoor unit installed in improper location Outdoor unit should be installed in a well ventilated area Outdoor temperature is too high Flashing or awning dcan be installed as needed. If the maximum cooling capacity cannot be satisfie, repl aceme nt of the ai r condi tioner is recomme nded. Building/windows not ; adequately sealed; large amount of in/out human traffic appl iance/ et c pr oduci ng an excess amount of heat. Adequately seal ; building/windows; reduce in/out traffic reduce use of appl iances/ et c creating excess heat

Troubleshooting Compressor Doesn t Run / Indoor Fan Doesn t Run Abnormal readings from the power supply of outdoor unit Check the circuit according to the circuit diagram When unit is cooling or heating, both the compressor and outdoor fan do not run Damaged outdoor main control board Damaged outdoor power module Replace the outdoor main control board Replace the outdoor power module Improper setting of temperature Adjust the set temperature Damaged outdoor fan motor Replace the outdoor fan motor When unit is cooling or heating, the compressor runs but the outdoor fan does not Incorrect wiring Damaged outdoor main control board Wire according to the circuit diagram Replace the outdoor main control board Damaged outdoor fan capacitor Replace the outdoor fan capacitor Malfunctioning compressor Replace the compressor When unit is cooling or heating, the outdoor fan runs but the compressor does not Poor contact or connection between the main control board and module Abnormal input of power module Re-fasten and secure the connection r Check if input is 230V. If not, replace the rectifie Abnormal output of power module Replace the power module When unit is cooling or heating, the outdoor fan runs but the compressor does not Compressor temperature is too high Incorrect wiring Damaged outdoor main control board Cool the compressor for 30 minutes before running Wire according to the circuit diagram Replace the outdoor main control board Burnt out or broken indoor fan motor wire Repair or change the indoor fan motor Fan doesn t run when FAN mode is set Incorrect wiring Break in circuit or damaged fan motor capacitor Wire according to the circuit diagram 1. Check circuit wiring 2. Replace the indoor main control board

Troubleshooting Water Leakage / Abnormal Sound and Vibration Water leakage Blockage or breakage of draining hose Refrigerant pipe wrap connector is not tight enough Replace the drainage hose Re-wrap refrigerant pipe more tightly Indoor unit fan contacts other parts Adjust the fan location Foreign object inside the indoor unit Remove the foreign object Compressor shakes excessively Adjust the compressor support washer and tighten any loose bolts Abnormal sound and shake Outdoor unit pipeline touches Inner plates are touching Separate the touching pipeline 1. Tighten connecting screws 2. Place shock-absorbing clay between plates Outdoor unit fan blade touches with the outer case Adjust louver position Abnormal sound inside compressor Replace the compressor Abnormal electromagnetic sound inside the four-way valve when heating Short circuit inside the electromagnetic valve. Replace the electromagnetic valve

Troubleshooting Compressor is too Hot Compressor too hot, starts and immediately stops or it stops frequently Check whether the outdoor unit is mounted properly. e.g. - outlet blockage; bad ventilation or directly under sunlight yes Change the mounting position no Ambient temperature t is too high yes For safe use no Check is the filer or the out door condenser is di rty yes Clean them no Check if the indoor and outdoor fans wrun too slowly and whether or not the outlet airflo is nor ma l yes Check the power supply circuit for motor on the controller is normal or replace the motor no Check the cooling system for blockage and that the frost on the capillary is not melting yes Replace blockage component no The power is abnormal yes Add voltage regulator no Check if the system operating pressure is normal to check whether the refrigerant is leaking or mixing with air (normal: 0.4-0.6 MPa for cooling system, 1.6-2.4 MPa for heating system) yes 1. Check for leaks 2. Recharge refrigerant no Check the circuit boards on the indoor and outdoor units and the power supply circuit assembly yes Change the assembly or main PCB no Check the U, V, W output of the outdoor power module. For more detailed information see Power Module Protection yes Change the power module no Check if the compressor is jammed or if the coil resistance is open or shorted. yes Change the compressor

Troubleshooting Procedures EEV Cooling Mode Step 1 To check the EEV valve operation, place a temperature probe on the input side of the EEV. Record the reading. Input Step 2 Next, place the temperature probe on the output side of the EEV. Record the reading. Compare the readings. Output With the compressor operating, the input side of the EEV should have a higher temperature reading than the output side of the EEV. No temperature drop across the EEV indicates the valve is fully open, whereas a temperature drop across the input and output indicates that the valve is metering refrigerant. No temperature charts are available for this check.

Troubleshooting Procedures EEV Heating Mode Step 1 To check the EEV valve operation, place a temperature probe on the input side of the EEV. Record the reading. Input Step 2 Next, place the temperature probe on the output side of the EEV. Record the reading. Compare the readings. Output With the compressor operating, the input side of the EEV should have a higher temperature reading than the output side of the EEV. No temperature drop across the EEV indicates the valve is fully open, whereas a temperature drop across the input and output indicates that the valve is metering refrigerant. No temperature charts are available for this check.

Troubleshooting Procedures Reversing Valve Cool Mode To check a reversing valve for proper operation in cool mode, there are four temperature readings required. They are grouped into two tests of two readings each. To condenser coil Compressor discharge Step 1 Place a temperature probe on the top input (compressor discharge) pipe of the reversing valve. Record the reading. Next, place the temperature probe on the lower left pipe (to condenser coil) of the reversing valve. Record the reading. Compare the readings. There should be a temperature difference of no more than 10 degrees. Suction line To accumulator Step 2 Place a temperature probe on the lower right pipe (suction line) of the reversing valve. Record the reading. Next, place the temperature probe on the lower middle pipe (to accumulator) of the reversing valve. Record the reading. Compare the readings. There should be a temperature difference of no more than 10 degrees. A temperature difference higher than the allowed difference indicates the valve has not shifted fully, or there is a blockage.

Troubleshooting Procedures Reversing Valve Heat Mode To check a reversing valve for proper operation in heat mode, there are four temperature readings required. They are grouped into two tests of two readings each. Suction line Compressor discharge Step 1 Place a temperature probe on the top input pipe (compressor discharge) of the reversing valve. Record the reading. Next, place the temperature probe on the lower right pipe (to suction line) of the reversing valve. Record the reading. Compare the readings. There should be a temperature difference of no more than 10 degrees. To accumulator To condenser coil Step 2 Place a temperature probe on the lower left pipe (to condenser coil) of the reversing valve. Record the reading. Next, place the temperature probe on the lower middle pipe (to accumulator) of the reversing valve. Record the reading. Compare the readings. There should be a temperature difference of no more than 10 degrees. A temperature difference higher than the allowed difference indicates the valve has not shifted fully, or there is a blockage.

Solenoid Check Troubleshooting & Reference Troubleshooting Procedures Reversing Valve Step 1 The reversing valve is powered up only during the heat mode of operation. Operating voltage is 208VAC-230VAC. To check the resistance value, disconnect the 4V plug from the AP1 board. Step 2 Using an ohmmeter, place the probes on the plug connected to the reversing valve solenoid. The ohms value should be 1.8K ohms. If the reading is infinite, replace the solenoid coil..

Troubleshooting Procedures Temperature Sensors The sensors used for indoor and outdoor temperature sensing are a negative temperature coefficient (NTC) type thermistor. These sensors include the indoor and outdoor unit ambient temperature sensors, indoor and outdoor unit tube temperature sensors, and outdoor unit discharge temperature sensor. The higher the temperature, the lower the resistance. To check these sensors, an ohmmeter, a cup of ice water, a stick thermometer, and the sensor resistance table for ambient temperature sensors for indoor and outdoor units will be required. Step 1 Disconnect the sensor plug from the control board. Step 2 Place the ohmmeter probes on the contacts of the sensor plug. Use the back of the plug for the test. Sticking the probes in the socket end may deform the contacts making for poor connections when reconnecting the plug back to the control board socket.

Troubleshooting Procedures Temperature Sensors Step 3 Place the sensor and the stick thermometer in the cup of ice water. Wait for the readings to stabilize before taking a reading. Read the resistance value on the ohmmeter and the temperature on the stick thermometer. Step 4 Compare these values to the sensor resistance table for the indoor and outdoor ambient temperature sensors. If the values vary greatly, replace the sensor. If the sensor is OK, reconnect the sensor to the control board.

Troubleshooting Procedures Compressor Motor Windings Step 1 To check the resistance value of the windings of the compressor, unplug the connector located on the wiring harness for the compressor. Step 2 Using an ohmmeter, measure the resistance between the terminals of the plug attached to the compressor. 1-2, 1-3, and 2-3. All readings should be the same. If a difference is encountered, the windings are bad. Replace the compressor.

Troubleshooting Procedures Compressor Motor Windings Step 3 Next, check the resistance from each terminal of the plug to ground. There should be no resistance indicated. If resistance is encountered, replace the compressor. If all check OK, reconnect the wiring harness plugs.

Troubleshooting Procedures Outdoor Fan Motor Cooling Only Unit Step 1 To check the resistance value of the windings of the outdoor fan, unplug the 3 wire connector S70 located on the control board. If the motor is hot, allow it to cool as there is a thermal overload switch internal to the motor that may give an open winding indication if tripped. Step 2 Measure the resistance between the terminals of the plug connected to the fan. Refer to the chart below for specific ohms values. An open reading between any two terminals indicates a bad winding, replace the fan motor.

Troubleshooting Procedures Outdoor Fan Motor Cooling Only Unit Step 3 Next, check the resistance from each terminal of the plug to ground. There should be no resistance indicated. If resistance is encountered, replace the fan motor. If all check OK, reconnect the plug to the control board.

Troubleshooting Procedures Outdoor Fan Motor Heat Pump Unit Step 1 To check the resistance value of the windings of the outdoor fan, unplug connector OFAN located on the AP1 control board, and the wires connected to the fan motor capacitor. The fan motor capacitor is located on the housing for the AP1 control board. If the motor is hot, allow it to cool as there is a thermal overload switch internal to the motor that may give an open winding indication if tripped. Step 2 Measure the resistance between all wires connected to the fan. Refer to the chart below for specific ohms values. An open reading between any two terminals indicates a bad winding, replace the fan motor.

Troubleshooting Procedures Outdoor Fan Motor Heat Pump Unit Step 3 Next, check the resistance from each terminal of the plug to ground. There should be no resistance indicated. If resistance is encountered, replace the fan motor. If all check OK, reconnect the plug to the control board.

Sensor Resistance Tables Resistance Table of Ambient Temperature Sensor for Indoor and Outdoor Units (15K)

Sensor Resistance Tables Resistance Table of Indoor and Outdoor Tube Temperature Sensors (20K)

Sensor Resistance Tables Resistance Table of Outdoor Discharge Temperature Sensor (50K)

Component Electrical Reference Indoor Fan Motor (Cooling Only) Voltages at the PG connector with the unit operating. Ohms reading taken with power off and plug disconnected from the board. Voltages at the PGF socket with the unit operating. Voltages are the same at any motor speed. Ohms reading taken with power off and plug disconnected from the board.

Component Electrical Reference Indoor Fan Motor (Heat Pump Only) Voltages at the PG connector with the unit operating. Ohms reading taken with power off and plug disconnected from the board. Voltages at the PGF socket with the unit operating. Voltages are the same at any motor speed. Ohms reading taken with power off and plug disconnected from the board.

Component Electrical Reference Swing Motor (Cooling / Heat Pump) The swing motor connector has the following ohm readings: Ohms readings taken with power off and plug disconnected from the board.

Component Electrical Reference Terminal Block (Cooling / Heat Pump)

Component Electrical Reference Outdoor Fan Motor (Cooling Only) The chart below shows the voltage and ohms values for the outdoor fan. Outdoor Fan S70 Socket on PCB2 Board. Ohms readings taken with power off and plug disconnected from the board.

Component Electrical Reference Outdoor Fan Motor (Heat Pump Only) The chart below shows the voltage and ohms values for the outdoor fan. Outdoor Fan OFAN Socket and capacitor wiring on the AP1 Board

Component Electrical Reference EEV (Heat Pump Only) Ohms reading taken with power off and plug FA disconnected from the board

Component Electrical Reference Reversing Valve (Heat Pump Only) Reversing Valve Ohms reading taken with power off and plug 4V disconnected from the board.

Quick Reference 16 SEER

Quick Reference 18 SEER