AU28: 0150503461 COMP FAN MOTOR HEATER STARTUP CAPACITOR 4-WAY VALVE SPRAY VALVE CN5(U) CON2 CN6(V) CN14 4-WAY CON3 CN7(W) HEATER ACFAN1 I P M CN11 control board ISPM TEMPERATURE SENSOR CN4(PTC) CN19 NOISE FILTER MODULE_COM )CN21 CN10 OUT/IN_COM P M V W:white R:red B:black BL:blue communication wire...
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AU48/60N: 0150502942 CN21 CN24 OUT/IN_COM CN11 CON3 MOD BUS MODULE_COM LED-DISPLAY CN7 TA CN6 TS CN5 TC SCP2 SCP1 CN4 TE CN3 TD CN2 LP (DOWN) (UP) CN1 HP ACFAN1 ACFAN2 - - + CN14 CN18 CN17 CN25 CN16 CN15 CN19 HEATER E N L3 L2 L1...
Troubleshooting: 1.Communication failure Is number of indoor units indicated by testing board Communication normal correct? Changeable? Is indoor unit address properly set? Without Reset address repetition? Are communication terminals of Reconnect indoor and outdoor units securely connected? Use shielded wire. Shield layer Is shielded wire should be grounded at single used for...
2.Sensor failure Are connectors of sensor properly Reconnect connected? Are resistance and temperature Replace sensor characteristics of sensor acceptable? Check PCB and replace 3.EEPROM failure Reinstall in right direction EEPROM chip installed firmly Is the PCB poorly Normal w elded? If chip is broken? Replace chip Check PCB and replace...
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5. Discharging temperature protection Are stop valves in gas pipe and liquid Open the stop valve pipe of outdoor unit open totally? Does EEV work properly during heating cycle? Check 1) Connector 2) Winding resistance 3) Repair outdoor EEV Valve 4) Mainboard Is actual discharging temperature detected Is discharging temperature Replace TD sensor...
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6. High pressure overhigh protection Are connectors of pressure switch Check and reconnect in good condition? replace PCB Is high pressure switch activated? Is pressure value detected by Replace high pressure switch pressure gauge above 3MPa? Are stop valves in suction pipe and liquid pipe of Open stop valve outdoor unit open?
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7 . Low pressure too low protection Are connectors of CN317pressure switch Check and reconnect in good condition? Is low side pressure switch activated? Replace PCB Is pressure valve detected by pressure gauge lower than Replace low pressure switch 0.05MPa? If outdoor stop valves of gas pipe Open stop valve and liquid pipe are open totally...
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8. Suction temperature protection Measure if the actual air return Check the suction temperature is over 40degree temperature Check the system: if the stop valve is normal; if EEV works normally; if the system is lack of refrigerant; if the system is clogged or leaks 9.