Daikin outdoor units come with a helpful feature – fault and error codes! When something goes wrong with your Daikin air conditioner, these codes provide valuable clues. They’re like the air conditioner’s way of saying, “Hey, I need some attention!” Let’s explore them and keep your system running smoothly.
Daikin Error Codes – Outdoor Unit
For error codes beginning with E, F, H, J, L, M or P, see table below.
For error codes beginning with 6, 7, 8 or 9, find causes here
For error codes beginning with A or C, find causes here
For error codes beginning with U, find causes here
| Outdoor Unit Error Codes and Contents | Supposed causes | Parts affected |
|---|---|---|
| E0 Protection devices activated (unified) | Protection device connected to outdoor unit PCB actuated Defective protection device connector contact | SkyAir, VRV, Chiller |
| E1 Defective outdoor unit PCB | Defective outdoor unit PCB Defective connection of inside/ outside relay wires | RA, SkyAir, VRV, Package, Chiller |
| E3 Actuation of high pressure switch (HPS) | Dirty outdoor unit heat exchanger Defective high pressure switch Clogged refrigerant piping Defective connector contact | RA, SkyAir, VRV, Package |
| E4 Actuation of low pressure switch (LPS) | Abnormally drop in low pressure Defective low pressure sensor Defective outdoor unit PCB Defective connector contact | SkyAir, VRV, Package, Chiller |
| E5 Inverter compressor motor or overheat | Inverter compressor lock High differential pressure Defective inverter PCB UVW connection error Defective connector contact | RA, SkyAir, VRV, Package, Chiller |
| E6 STD compressor motor overcurrent/lock | Defective compressor Defective control PCB The stop valve is not opened | RA, SkyAir, VRV, Package |
| E7 Malfunction of outdoor unit fan motor system | Fan motor failure Neglect to connect or defective connection of harness/ connector between the fan motor and the PCB Fan does not rotate due to foreign matters caught in it | RA, SkyAir, VRV, Package, Chiller |
| E8 Overcurrent of inverter compressor | Defective compressor Defective inverter main circuit capacitor Defect of outdoor unit PCB Defect of power transistor | RA, Chiller |
| E9 Malfunction of electronic expansion valve coil | Disconnection of connectors from electronic expansion valves Defective electronic expansion valve coil Defective outdoor unit control PCB | SkyAir, VRV, Package, Chiller |
| EA Malfunction of four way valve or cool/heat switch | Defective four way valve Shortage of gas Defective outdoor unit PCB Defective thermistor | RA |
| EC Malfunction of entering water temperature | Cooling water temperature abnormality Defective outdoor unit PCB Defective thermistor | VRV |
| F3 Malfunction of discharge pipe temperature | Defective discharge pipe thermistor Abnormal discharge pipe temperature Defective outdoor unit control PCB Defective connector contact | RA, SkyAir, VRV, Package, Chiller |
| F6 Abnormal high pressure or refrigerant overcharged | Refrigerant overcharged Disconnection of heat exchanger deicer thermistor Disconnection of outdoor air thermistor Disconnection of liquid pipe temperature thermistor Defective outdoor unit PCB | RA, SkyAir, VRV, Package |
| H0 Malfunction of sensor system of compressor | Harness is disconnected, or defective connection Defective PCB | RA, Chiller |
| H1 Malfunction of room temperature sensor or humidifier unit damper | Defective limit switch Defective damper | RA, Chiller |
| H3 Malfunction of high pressure switch (HPS) | Defective high pressure switch Broken wire Defective outdoor unit PCB Defective connector contact | RA, SkyAir, VRV, Package, Chiller |
| H4 Malfunction of low pressure switch (LPS) | Defective low pressure switch Broken wire Defective outdoor unit PCB Defective connector contact | SkyAir, VRV, Chiller |
| H5 Malfunction of compressor motor overload thermistor | Defect of compressor motor overload thermistor Defective connector contact | RA, Chiller |
| H6 Malfunction of position detection sensor | Faulty contact of compress or cable Defective compressor Defective outdoor unit PCB | RA, Package, Chiller |
| H7 Malfunction of outdoor unit fan motor signal | Abnormal signal from fan motor (Circuit failure) Disconnection/Short circuit in fan motor leads or disconnection of connector Defective inverter PCB | SkyAir, VRV, Package, Chiller |
| H8 Malfunction of compressor input (CT) system | Defective power transistor Defective reactor Faulty wiring of inverter system Defective outdoor unit PCB | RA, Chiller |
| H9 Malfunction of outdoor air thermistor | Defective connection of thermistor Defective outdoor unit PCB Defective outdoor air thermistor | RA, SkyAir, VRV, Package, Chiller |
| HC Malfunction of (hot) water temperature thermistor | Defective connection of thermistor Defective outdoor unit PCB Defective water temperature thermistor | SkyAir, VRV, Chiller |
| HF Alarm in thermal storage unit or storage controller | Thermal storage group defective wiring Defective setting Excess of thermal storage tank numbers | VRV |
| HJ Malfunction of thermal storage tank water level | Low water level Defective switch setting Water level detecting sensor failure Defective connector contact | RA, SkyAir, VRV, Package |
| J1 Malfunction of pressure sensor | Defective pressure sensor connector contact Defective pressure sensor Defective outdoor unit PCB | SkyAir, VRV, Package, Chiller |
| J2 Malfunction of current sensor of compressor | Defective current sensor Defective compressor Defective outdoor unit PCB | RA, SkyAir, VRV, Package, Chiller |
| J3 Malfunction of discharge pipe thermistor | Defective connection of thermistor Defective discharge pipe thermistor Defective outdoor unit PCB | RA, SkyAir, VRV, Package, Chiller |
| J4 Malfunction of low pressure equivalent saturated temperature sensor system | Defective connection of thermistor Defective thermistor Defective outdoor unit PCB | VRV, Chiller |
| J5 Malfunction of suction pipe thermistor | Defective connection of thermistor Defective suction pipe thermistor Defective outdoor unit PCB | SkyAir, VRV, Package, Chiller |
| J6 Malfunction of heat exchanger thermistor | Defective connection of thermistor Defective heat exchanger thermistor Defective outdoor unit PCB | RA, SkyAir, VRV, Package, Chiller |
| J7 Malfunction of thermistor (Refrigerant circuit) | Defective connection of thermistor Defective liquid pipe thermistor Defective outdoor unit PCB | SkyAir, VRV, Package, Chiller |
| J8 Malfunction of thermistor (Refrigerant circuit) | Defective connection of thermistor Defective liquid pipe thermistor Defective outdoor unit PCB | RA, SkyAir, VRV, Package, Chiller |
| J9 Malfunction of thermistor (Refrigerant circuit) | Defective connection of thermistor Defective gas pipe thermistor Defective outdoor unit PCB | RA, SkyAir, VRV, Package, Chiller |
| Outdoor Unit Error Codes and Contents | Supposed causes | Parts affected |
|---|---|---|
| JA Malfunction of high pressure sensor | Defective connector contact Connection of low pressure sensor in mistake for high pressure sensor Defective high pressure sensor Defective outdoor unit PCB | SkyAir, VRV, Package, Chiller |
| JC Malfunction of low pressure sensor | Defective connector contact Connection of high pressure sensor in mistake for low pressure sensor Defective low pressure sensor Defective outdoor unit PCB | SkyAir, VRV, Package, Chiller |
| JE Malfunction of oil pressure sensor or sub-tank thermistor | Defective connector contact Defective sub-tank thermistor Defective outdoor unit PCB | VRV |
| JF Malfunction of oil level sensor or heating heat exchanger thermistor | Defective connector contact Defective heat exchanger thermistor Defective outdoor unit PCB | VRV |
| L0 Malfunction of inverter system | Shortage of power supply capacity Defective power transistor Defective outdoor unit PCB | VRV, Chiller |
| L1 Malfunction of inverter PCB | Defective compressor wiring Defective outdoor unit fan motor Blown fuse Defective inverter PCB | SkyAir, VRV, Package, Chiller |
| L3 El.compo. box temperature rise | Fin temperature rise due to short circuit Defective outdoor unit fan motor Defective power transistor Defective outdoor unit PCB | RA, SkyAir, VRV, Chiller |
| L4 Malfunction of inverter radiation fi n temperature rise | Fin temperature rise due to short circuit Defective fi n thermistor | RA, SkyAir, VRV, Package, Chiller |
| L5 Inverter instantaneous overcurrent (DC output) | Defective compressor coil (such as wiring disconnection or insulation failure) Compressor startup failure (mechanical lock) Defective inverter PCB | RA, SkyAir, VRV, Package, Chiller |
| L6 Inverter instantaneous overcurrent (AC output) | Overcharge of refrigerant amount Shortage of power supply capacity Defective compressor Defective inverter unit | VRV, Chiller |
| L8 Malfunction of overcurrent inverter compressor | Compressor overloaded Wiring disconnection in compressor coil Disconnection of compressor wiring Defective inverter PCB | RA, SkyAir, VRV, Package, Chiller |
| L9 Malfunction of inverter compressor startup error (Stall prevention) | The stop valve is not opened Defective compressor Error in wire connections to compressor Large differential pressure before compressor startup Defective inverter PCB | SkyAir, VRV, Package, Chiller |
| LA Malfunction of power transistor | Defective power transistor Defective compressor Defective inverter PCB | VRV, Chiller |
| LC Malfunction of transmission between control and inverter PCB | Defective connection between the inverter PCB and the control PCB External factors (e.g. noise) Defective inverter compressor Defective control PCB (transmission block) | RA, SkyAir, VRV, Package, Chiller |
| M1 Malfunction of central remote controller PCB | Defective central remote controller PCB | RA, SkyAir, VRV, Package, Fan Coil |
| M8 Malfunction of transmission between optional controllers for centralized control | Other centralized control power disconnection Centralized control reset switch ON Defective transmission wiring Central remote controller address change | RA, SkyAir, VRV, Package, Fan Coil |
| MA Improper combination of optional controllers for centralized control | Improper combination of optional controllers for centralized control More than one master controller is connected Faulty setting of centralized control Defect of centralized control | RA, SkyAir, VRV, Package, Fan Coil |
| MC Address duplication, improper setting | Address duplication of central remote controller | RA, SkyAir, VRV, Package, Fan Coil |
| PO Shortage of refrigerant amount (thermal storage unit) | Shortage of refrigerant Clogged refrigerant piping | VRV, Chiller |
| P1 Power voltage imbalance or inverter PCB | Open phase Interphase voltage imbalance Defective capacitor in the main circuit Defective wiring in the main circuit Defective inverter PCB | SkyAir, VRV, Package, Chiller |
| P2 Automatic refrigerant charge operation stop | The stop valve is not opened Closed valve of refrigerant tank | SkyAir, VRV, Package, Chiller |
| P3 Malfunction of thermistor in switch box | Defective connection of thermistor Defective reactor thermistor Defective inverter PCB | RA, SkyAir, VRV, Package, Chiller |
| P4 Malfunction of radiation fin temperature sensor | Defective radiation fi n temperature thermistor Defective inverter PCB Defective INV. compressor Defective fan motor | RA, SkyAir, VRV, Package, Chiller |
| P8 Heat exchanger freezing protection during automatic refrigerant charging | (Close the refrigerant cylinder. Start again from step 1.) | SkyAir, VRV, Package |
| P9 Malfunction of fan motor (humidifier unit) | __ | SkyAir, VRV, Package, Heat reclaim ventilator |
| PA Refrigerant cylinder during automatic refrigerant charging | Refrigerant cylinder of master unit is empty | SkyAir, VRV, Package |
| PA Broken wire of heater (humidifier unit) | Defective heater unit Defective thermistor Defective outdoor unit PCB | RA |
| PC Refrigerant cylinder during automatic refrigerant charging | Refrigerant cylinder of slave unit 2 is empty | VRV, Package |
| PE Automatic refrigerant charge operation nearly completed | __ | SkyAir, VRV, Package |
| PH Refrigerant cylinder during automatic refrigerant charging | Defective heater unit Defective connector contact Defective thermistor Defective outdoor unit PCB | RA, VRV, Package |
| PJ Malfunction of capacity setting (Outdoor unit PCB) | Capacity setting adaptor is not installed Improper capacity setting adaptor Defective outdoor unit PCB | SkyAir |
| PJ Improper combination between inverter and fan driver | Mis-matching of type of PCB Improper (or no) fi eld setting after replacing outdoor unit main PCB | SkyAir, VRV, Package, Chiller |
