Protection / Error Codes

Example of a Serial Number sticker.

The following error codes are provided to help troubleshoot your system.

To determine which Error codes apply to your system, look at the serial number of your Outdoor Unit. Generally it can be found on the  side or rear or the unit, where the refrigeration lines connect. On some units it will be located behind the wiring cover

In the event that you can’t find your serial number, your model number can also help figure out the correct error codes to use.

The prefix will tell you which M series Error Codes are correct for your unit

Example:
Serial #: M3-XXXXXX-WMMS-XXXXXXX(XX)-XXXXXXXXX
Use M3 Error Codes to diagnose

M6 Single & Multi Zone (56),(57),(58),(59)M8-(56)-G1-1198YM (56) On-Grid Solar SystemM8-G2-1201YM Single Zone (56) On-Grid Solar Heat PumpM8 (86) All DC Solar Heat Pump(78)1 SERIES 18.8-21.5 SEER Single Zone SystemM2 Single and Dual Zone 13/14 SEER SystemsM3 Single Zone 13 SEER SystemsM1 16 SEER (57)2,3 SystemsM1 13 SEER SystemsM1 48 Series SystemsM1 46 Series SystemsPTAC SystemsVRF Error CodesSHCR Error codes

M6 Single & Multi Zone (56),(57),(58),(59)

Protection/ Error Code Description Indoor Unit LED Display
C1 Current arc protection Running LED-Off 3S, Blinks 12 times
C2 Current leakage protection Running LED-Off 3S, Blinks 13 times
C3 Mis-wiring protection Running LED-Off 3S, Blinks 14 times
C5 Jumper error protection Running LED-Off 3S, Blinks 15 times
C6 No-ground Running LED-Off 3S, Blinks 16 times
Cd Too much CO2 protection TBD
CF Current short-out protection TBD (Buzzer will sound once every 2 sec.)
d1 WSHP: UV light error TBD
E0 Commercial: Water pump overload/error/flow switch error Running LED-Off 3S, Blinks 10 times
E1 System high pressure protection Running LED-Off 3S, Blinks 1 time
E2 Anti-freezing protection (heat exchanger-ID, OD) Running LED-Off 3S, Blinks 2 times
E3 Low pressure protection (run cooling when OD is too cold) Running LED-Off 3S, Blinks 3 times
E4 Compressor dischage pressure too high Running LED-Off 3S, Blinks 4 times
E5 System/compressor current too high Running LED-Off 3S, Blinks 5 times
E6 Communication error (ID-OD) Running LED-Off 3S, Blinks 6 times
E7 Mode clash (some Indoor Units set to run cooling/fan, some set to run heating) Running LED-Off 3S, Blinks 7 times
E9 Indoor Unit Water Full Error Cooling LED Flashing/Heating LED Flashing (both flashing)
EA VRF: Oil valve protection TBD
Ec Commercial & VRF: Water flow protection (lack of water flow) TBD
Ed System temperature too high TBD
EE Memory chip error (U5) Heating LCD-Off 3S, Blinks 15 times
EF Outdoor fan motor overload TBD
EL Fire alarm TBD
EP Shell top high temperature protection TBD
F0 System refrigerant lack or restriction protection Cooling LED-Off 3S, Blinks 10 times
F3 Outdoor abmient temperature sensor error Cooling LED-Off 3S, Blinks 3 times
F8 Incoming water temperature sensor error Cooling LED-Off 3S, Blinks 8 times
F9 Outgoing water temperature sensor error Cooling LED-Off 3S, Blinks 9 times
FA Oil temperature sensor error TBD
Fd Suction gas temperature sensor error TBD
FE User side water sensor error TBD
FL Water tank-middle sensor error TBD
FP CO2 checking error TBD
FU Shell top temperature sensor error protection TBD
H1 Heating-Defrosting, or oil return TBD
H2 Static electric de-dust protection Heating LED-Off 3S, Blinks 2 times
H3 Compressor over-temperature protection Heating LED-Off 3S, Blinks 3 times
H4 System abnormal (many different other reasons…) Heating LED-Off 3S, Blinks 4 times
H5 IPM abnormal / Control Module Protection
IPM Module protection, could be caused by over-charged refrigerant/high pressure (bad manifold gauge), restricted refrigerant flow or kinks on refrigerant pipes. Board failure due to age, insects, water exposure, power surge, lightning; or high current through the control board caused by any of these: failed fan motor, damaged fan blade, dirty coils outdoor and indoor units, airflow restricted by dirty filter, kinks in the copper lines, too much refrigerant, locked compressor, or other reasons.		 Heating LED-Off 3S, Blinks 5 times
H6 Indoor fan motor-no feedback Running LED-Off 3S, Blinks 11 times
H7 Compressor loses steps, not being able to check rotor position Heating LED-Off 3S, Blinks 7 times
HC PFC board abnormal / PFC protection Heating LED-Off 3S, Blinks 6 times
HE Compressor de-managet protection (rotor locked /doesn’t rotate) Heating LED-Off 3S, Blinks 14 times
L0 Airflow switch error TBD
L1 Humidity sensor error TBD
L2 Water level switch error / hot water tank level switch error TBD
L3 Outdoor DC motor error (L3 for dual -mtor 1, LA for motor 2) Running LED-Off 3S, Blinks 23 times
L4 Filter clogged TBD
L5 Circulating water temperature sensor error TBD
L6 System capacity insufficient TBD
L7 Water pressure switch protection TBD
Lc Starting failure Heating LED-Off 3S, Blinks 11 times
Ld Power phase loss/lack TBD
LE Compressor locked Running LED-Off 3S, Blinks 22 times
LF Compressor over-speed protection TBD
LH Indoor ambient temperature too high TBD
LL Indoor ambient temperature too low TBD
LP Indoor-Outdoor units don’t match or power line connection error Running LED-Off 3S, Blinks 19 times
P0 Driving module resumed TBD
P5 Driving board checking-compressor current too high Heating LED-Off 3S, Blinks 15 times
P6 Driving board checking-communication error with indoor board Heating LED-Off 3S, Blinks 16 times
P7 Radiator loose, or IPM /PFC board sensor abnormal /error Heating LED-Off 3S, Blinks 18 times
P8 Radiator loose, or IPM /PFC board too hot Heating LED-Off 3S, Blinks 19 times
P9 AC contactor protection TBD
PA AC current protection (incoming) TBD
Pc Current checking-circuit error or current sensor error TBD
Pd Current checking-connection error (U-V-W not connected accordingly) TBD
PE Temperature sensor drifting protection TBD
PF Driving board-ambient temperature sensor error TBD
PH DC incoming voltage too high (program checking) Cooling LED-Off 3S, Blinks 11 times
PL DC incoming voltage too low (program checking) Cooling LED-Off 3S, Blinks 21 times
PP AC incoming power abnormal (too low or too high) TBD
PU Capacitor-charging circuit error Heating LED-Off 3S, Blinks 17 times
U7 4-way switch valve abnormal Heating LED-Off 3S, Blinks 20 times
U6 Oil temperature too high Heating LED-Off 3S, Blinks 16 times
U4 Compressor rotation reversed Heating LED-Off 3S, Blinks 14 times
U5 Rectifying current checking error Heating LED-Off 3S, Blinks 13 times
U3 DC main bus voltage drop Heating LED-Off 3S, Blinks 20 times
U1 Compressor phase current checking circuit error Heating LED-Off 3S, Blinks 13 times
U2 Compressor phase loss protection Heating LED-Off 3S, Blinks 12 times
UC Filter needs to be cleaned TBD
U8 PG motor (indoor) checking circuit error Running LED-Off 3S, Blinks 17 times
U9 Outdoor fan motor checking circuit error Running LED-Off 3S, Blinks 18 times
UF De-actuate remote or control, from a long distance TBD
C7 PTC heater sensor error Heating LED-Off 3S, Blinks 9 times
FJ Discharge/vent air temperature sensor error TBD
L8 Storage tank water level switch error TBD
d3 AC condensate: anti-freezing sensor error TBD
d4 Domestic water: anti-freezing sensor error TBD
d5 Return water sensor error TBD
d6 Defrost coil sensor error TBD
d7 Back-up hot water temperature sensor error TBD
d8 Hot water outlet temperature sensor error TBD
d9 Hot water inlet temperature sensor error TBD
db Temp. Sensor Error-after metering device (cap. Tube, or EXV) TBD
dc Temp. Sensor Error-suction tube TBD
dP Temp. Sensor Error-discharge tube TBD
dL Low voltage reluctance/reluctor error TBD
L9 Compressor Protection-calculated input is too high Running LED-Off 3S, Blinks 20 times
dF Temp. Sensor Error-solar water heater-water outlet TBD
dH Temp. Sensor Error-solar water heater-assistant ele. heater TBD
dU Door-lock sensor: card is not in TBD
dJ AC phase protection (lost or reversed) TBD
d0 Fan motor speed communication error TBD
Eo Special function board error TBD
dn Mulitiple zone-pipe connection doesn’t match with comm. wire connection TBD
Cn Not for AC: Buring gas density too high Cooling LED-Off 3S, Blinks 23 times
Fn Not for AC: Buring gas sensor error Running LED-Off 3S, Blinks 21 times
HP Solar AC: solar power input voltage is higher than 180V TBD
dA AHU or RT: discharge air-relative humidity sensor error TBD
dE AHU or RT: fresh air-relative humidity sensor error TBD
Fr AHU or RT: fresh air-temp. sensor error TBD
UA DC inverter driving error 1 TBD
dr AHU or RT: air flow pressure sensor error TBD
Ub DC inverter driving error 2 TBD
Ud DC inverter driving error 3 TBD
UE DC inverter driving error 4 TBD
LU Compressor power input limit / decrease HZ (system power input) Cooling LED-Off 3S, Blinks 24 times
LA Outdoor unit fan motor protection (not rotating, or not connected). If 2 motors, motor 1-L3, motor 2-LA Running LED-Off 3S, Blinks 24 times
A5 Condensing coil-inlet temp. sensor error (=F5 in commercial units) TBD
A7 Condensing coil-outlet temp. sensor error (=F7 in commercial units) TBD
e4 Compressor dischage temp. (=pressure) too high TBD
e8 Over-load protection (outdoor coil temp. too high) TBD
e1 Dicharge pressure sensor error TBD
ee DC inverter driving chip error TBD
JF Indoor unit-testing board comm. Error (after 3-minutes) TBD
rF RF module error (once powered, the MCU tries to send commands, via SPI, to RF, if RF doesn’t receives it, error shows) TBD
Uu Solar AC: battery bank discharged too much and the output voltage is lower than 295V TBD
no For VRF groups: DC unit’s display board can not receive any data from the fixed speed comp. unit, will show “no” after 8 seconds TBD
E6+IDU Temp. Communication error (ID display-OD main board) and outdoor temperature sensor error TBD
E7+ODU Temp. Communication error (ID unit-OD unit) and outdoor temperature sensor error TBD
Fu AHU or RT: dust sensor error TBD
e2 Warning: water flow low TBD
e3 Oil level low protection TBD
e7 System pressure difference protection TBD
eA Heat exchanger-pressure transducer sensor error (similar to lower pressure transducer protection) TBD
eC Oil-pressure transducer sensor error (similar to lower pressure transducer protection) TBD
e0 Economizer-discharge temp. sensor error TBD
e9 Economizer-discharge pressure sensor error TBD
eF Compressor brand sensor error TBD
bH Water pump temp. sensor TBD
oE Any other error that the outdoor unit needs to stop TBD
E8 Anti-high temperature protection Running LED-Off 3S, Blinks 8 times
E9 Anti-cold blowing (discharging) protection Running LED-Off 3S, Blinks 9 times
F1 Indoor air temp. sensor error/bad-broken, shorted Cooling LED-Off 3S, Blinks 1 time
F2 Indoor coil temp. sensor error/bad-broken, shorted… Cooling LED-Off 3S, Blinks 2 times
F4 Outdoor coil temp. sensor error/bad-broken, shorted… Cooling LED-Off 3S, Blinks 4 times
F5 Compressor discharge temp. sensor error/bad-broken, shorted… Cooling LED-Off 3S, Blinks 5 times
F7 Cooling-oil return error Cooling LED-Off 3S, Blinks 7 times
FC Slide door error, or air louver mechanism error TBD
FE Over-load sensor error TBD
H8 Water level-high /overflow protection Heating LED-Off 3S, Blinks 8 times
H9 Ele. heater error Heating LED-Off 3S, Blinks 9 times
b7 Outlet temp. sensor error Cooling LED-Off 3S, Blinks 22 times
b5 Inlet temp. sensor error Cooling LED-Off 3S, Blinks 19 times
d1 DRM running mode 1
d2 DRM running mode 2
d3 DRM running mode 3

M8-(56)-G1-1198YM Single Zone (56) On-Grid Solar Heat Pump

M8-(56)-G1-1198YM Error Code list online

E0 Driving board communication error
E1 Indoor unit air temperature sensor error
E3 Indoor unit tube temperature sensor error
E6 System refrigerant high pressure protection
E7 System refrigerant low pressure protection
E8 Indoor unit fan motor no feedback
F1 Outdoor board IPM abnormal
F2 Outdoor board inverter abnormal
F3 Outdoor temperature sensor errors-discharge, tube, ambient air, etc.
F4 Anti-freeze protection
F5 Outdoor compressor discharge temperature too high
F6 Outdoor compressor overload protection
F7 Over current protection

M8-(56)-G2-1201YM Single Zone (56) On-Grid Solar Heat Pump

Code# Code Descriptions What to check
H1 Protection-Refrigeration System High Pressure Copper line vacuumed, leakage, refrigerant charge, fan motors working properly, filters/coils are clean
H2 Protection-Refrigeration System Low Pressure Copper line leakage, refrigerant charge, ambient temperatures
E1 AC Voltage too high or too low AC voltage ranges
E2 DC Voltage too high AC voltage ranges
E3 DC Voltage too low DC voltage ranges
E4 Protection-AC input
current too high		 AC current ranges, surge protector
E5 Protection-Compressor
current too high		 Compressor-resistances between any 2 leads (less than 1 Ohm), and any 1 lead against ground (must be OL), refrigerant charge too much, fan motor failure
E6 System Pressure too high Check refrigerant levels
E7 Compressor-Phase loss Compressor-lead wire connections matched diagrams, correct circuit breaker/wire connections
E8 Protection-IPM not working properly IPM board components
E9 Starting failure AC input, DC input, compressor, control boards, etc.
F0 Driving board-communication error Control board
F1 Indoor unit temperature sensor error Temperature sensor connection and resistance
F2 Outdoor unit ambient temperature sensor error Temperature sensor connection/contact and resistance
F3 Indoor unit coil sensor error Temperature sensor connection/contact and resistance
F4 Outdoor unit defrost sensor error Temperature sensor connection/contact and resistance
F5 Compressor discharge temperature sensor error Temperature sensor connection/contact and resistance
F6 Protection-Indoor unit coil anti-freeze Filter/coil clean, fan motor working, refrigerant charge
F7 Protection-compressor discharge tube high temperature Copper line vacuumed properly, filter/coil clean, temperature sensor connection/contact and resistance
F8 Outdoor fan motor speed is not satisfied Fan blade clogged, motor resistance, control board
F9 Protection-Refrigerant leaking Refrigerant leaking, all connections especially flare/nuts
FA Protection-indoor fan motor no feedback Fan motor wire connection/resistances, control board
FC Outdoor unit fan motor error Fan motor wire connection/resistances, control board

Protection and Error Codes

Code Descriptions
C1 AC Voltage higher than 254V, unit stops to work, error code stays on until AC voltage drops below 254V
C2 AC Voltage lower than 197V, unit stops to work, error code stays on until AC voltage rises above 197V
C4 DC Voltage higher than 350V, unit stops to work, error code stays on until DC voltage drops below 350V
C5 DC Voltage lower than 150V, unit keeps on working, code stays on until DC voltage rises above 150V
C7 Compressor over current/over load protection
C8 Incorrect wiring between indoor unit and outdoor unit, unit stops to work until correction is made
P1 Refrigerant pressure too HIGH, unit stops to work until error is cleared
P2 Refrigerant pressure too LOW, unit stops to work until error is cleared
P6 4-way switching valve abnormal
A1 Error of temperature sensor for indoor air temperatures-open, short or other issues
A2 Error of temperature sensor for indoor coil tube temperatures-open, short or other issues
A3 Error of temperature sensor for outdoor air temperatures-open, short or other issues
A4 Error of temperature sensor for outdoor coil tube temperatures-open, short or other issues
A5 Error of temperature sensor for outdoor compressor discharge temperatures-open, short or other issues
A6 High temperature at compressor discharge tube, unit stops to work until error is cleared
A7 High temperature at outdoor coil, unit stops to work until error is cleared
AC Anti-freeze/anti-low temperature at indoor coil tube, unit keeps on working
F3 No feedback at indoor fan motor
F6 No feedback at outdoor fan motor
H1 Compressor over load/over current protection
H7 Compressor input power phase error
H8 Driving board check compressor over current
b3 Radiator or IPM, PFC module-Temperature sensor abnormal
b4 Radiator or IPM, PFC module-Temperature too high
b5 Compressor-loses steps, not detecting rotator position
b6 PFC abnormal or protection
b7 IPM abnormal or protection
b9 Starting failure
bb Communication error between driving board-main board
J3 Storage chip error at driving board
J7 Suction temperature sensor-open, short or other issues
J9 Outdoor coil middle temperature sensor-open, short or other issues

M8 Single Zone (86) All DC Solar Heat Pump

ERROR CODE DESCRIPTION TROUBLE SHOOTING
E1 Indoor Unit-Air Temperature Sensor error Check resistances, contacts to the board
E2 Indoor Unit-Tube Temperature Sensor error Check resistances, contacts to the board
E3 Indoor Unit-Fan Motor no feedback/error Check motor, resistances, contacts to the board and
filter
E4 Outdoor Unit-voltage between + and – lower than 40VDC (12-24K 48V) or 20V (09K 24V) Check charge controller, panel specs/connections
E5 Outdoor Unit-voltage between + and – higher than 60VDC (12-24K 48V) or 30V (09K 24V) Check charge controller, panel specs/connections
E6 Outdoor Unit-refrigeration pressure too low Check refrigerant pressure, and low pressure switch
E7 Outdoor Unit-refrigeration pressure too high Check fan motor, high pressure switch, and clean the filter
E8 Outdoor Unit-refrigerant is low Check refrigerant pressure, sensor, potential leak points before recharging
E9 Indoor Unit-Protecting the coil from becoming frozen Check refrigerant pressure, charge, sensor, potential leak points before recharge. Check Indoor fan motor, filter, and clean the coil.

(78)1 SERIES 18.8-21.5 SEER Single Zone System

Error and Protection Codes

Indication on the outdoor unit

When the unit has an issue, or the compressor stops running, the LEDs on the outdoor control board will show the error sequence automatically.

Key: ★ : LIGHT ○ : FLASHING LIGHT X : OFF

Outdoor Unit
Failure Description		 LED 1 LED 2 LED 3 Possible Cause
Lights will flash every second for the following faults
Normal Operation x x x
Outdoor
coil temperature sensor issue		 ★ X ★
  • Outdoor coil sensor connection is loose
  • Outdoor coil temperature sensor has failed
  • Outdoor control board has failed
Compressor exhaust temperature sensor issue ★ X X
  • Compressor exhaust temperature sensor connection is loose
  • Compressor exhaust temperature sensor has failed
  • Outdoor control board has failed
Communication failure between Indoor Unit and Outdoor Unit X X ○
  • Communication cable connection is loose
  • Communication cable has failed
  • Connection between the filter board and the outdoor control board is incorrect or loose
  • Connection between the filter board and the terminal is incorrect or loose
  • Indoor unit control board failure
  • PFC board failure
  • Power board failure
  • Outdoor control board failure
Current
Overload Protection		 ★ ○ X
  • Fan motor is running abnormally
  • Condenser and evaporator are dirty
  • Air inlet and outlet are abnormal
Maximum
Current Protection		 ★ ○ ★
  • Outdoor control board has a short
    circuit
  • Drive board has a short circuit
  • Other component has a short circuit
Communication issue between Outdoor Unit and Driver X ★ ★
  • Connection wires connection loose
  • Outdoor board or drive board failure
Outdoor
EEPROM issue		 ★ ★ ★
  • EEPROM chip is loose
  • EEPROM chip is inserted backwards
  • EEPROM chip has failed
Compressor exhaust temperature is too high protection X ○ ★
  • Compressor exhaust temperature sensor failure
  • Unit does not have enough refrigerant
Outdoor ambient temperature sensor issue ★ ★ X
  • Outdoor ambient temperature sensor connection is loose
  • Outdoor ambient temperature sensor failure
  • Outdoor control board failure
Compressor shell temperature too high protection X ★ ○
  • Compressor exhaust temperature sensor connection is loose
  • Unit does not have enough refrigerant
Anti-freeze protection with cooling or Overload protection with heating in Indoor Unit X ○ ○
  • Indoor unit coil temperature sensor is loose
  • Indoor unit coil temperature sensor failure
  • Indoor unit control board failure
  • Refrigerant system is running abnormally
Compressor
drive issue		 ○ X ○
  • Outdoor drive board failure
  • Compressor failure
  • Outdoor control board failure
Locked
rotor outdoor fan motor protection		 ○ ○ ★
  • Outdoor fan motor connection is loose
  • Outdoor fan has blockage
  • Fan motor failure
  • Outdoor control board failure
Outdoor coil anti-overload protection with cooling X ★ X
  •     System has too much refrigerant
  •     Outdoor fan motor failure
  •     Dirty condenser
  •     Air inlet and/or air outlet of the indoor unit or outdoor unit is blocked or abnormal
IPM module protection X ○ X
  • IPM board failure
  • Outdoor unit fan is broken
  • Outdoor unit motor failure
  • Outdoor unit fan is blocked
  • Condenser requires cleaning
  • Outdoor unit installed improperly
PFC
protection		 ○ X X
  • PFC failure
  • Outdoor Unit drive board failure
Compressor
preheating process		 ○ ★ ○
  • Unit in normal mode during cold weather
Outdoor
board chip issue		 ★ X ○
  • Wrong drive board
  • Wrong compressor
AC voltage
too high or too low protection		 ★ ★ ○
  • Supply voltage is higher or lower than normal
  • Internal voltage supply of the unit is higher or lower than normal
DC
compressor		 ○ ○ X
  • Outdoor drive board failure
  • Compressor failure
Outdoor ambient temperature too low protection ★ ○ ○
  • Outdoor ambient temperature is too low
Light flash every 2 seconds for the following faults
Outdoor radiator overheated protection ○ X X
  • Radiator sensor failure
  • Detection circuit of the sensor on control panel failure
System high
pressure failure protection		 ○ ○ X
  • Pressure switch failure
  • Pressure detection switch on the control panel failure
  • System pressure measurement exceeds system limit

 

 

When the compressor is in operation

Key:     ★ : LIGHT          ○ : FLASHING LIGHT                X : OFF            Flash cycle is 1 second

No. LED 1 LED 2 LED 3 Reason current operating frequency of the compressor is limited
Lights will flash every second for the following faults
1 ○ ○ ○ Normal frequency increasing and decreasing. No limitation
2 x x ★ Frequency decreasing or prohibition of frequency increasing caused by over current
3 x ★ ★ Frequency decreasing or prohibition of frequency increasing caused by anti-freezing of refrigeration or anti-overload in heating
4 ★ x ★ Frequency decreasing or prohibition of frequency increasing caused by compressor discharge temperature is too high
5 Limit to maximum operating frequency caused by low voltage
6 ★ ★ ★ Operation at fixed frequency (in case of capability measuring or compulsory operation at fixed frequency)
7 ○ x x Protective frequency decreasing against outdoor overload (over power, over frequency conversion rate, over torque, and detection of DC under-voltage)
8 ★ x x Frequency decreasing caused by indoor and outdoor communication fault
9 x ★ ○ Frequency decreasing or prohibition of frequency rising protection against overload of outdoor coiled pipe
10 x ★ x Frequency decreasing or prohibition of frequency increasing for power-saving when it is being used simultaneously with other applications

 

Indication on the Indoor Unit

The 88 display of the indoor display board will show the error code
automatically when the unit has the following issue

Error Code Error Reason current operating frequency of the compressor is limited
EA Error code indicates an issue with communication between the display board and control board
  • Connection between display board and control board is loose
  • Indoor control board failure
  • Wiring to the display board is incorrect

 

If the unit has the following issue, and the compressor stops running, press the sleep button on the remote controller 10 times in 10 seconds, and the Indoor unit 88 display on the display board will show the error code. If two malfunctions happen at the same time, pressing the sleep button an additional 10 times in 10 seconds will display the second error code.

Note:
When you perform a troubleshooting inquiry using the Indoor unit 88 display, the error code will be displayed after entering the command with the remote control. If the error code can’t be displayed on the indoor unit, you will need to check the LED display board on the outdoor unit.

 

Key:★ : LIGHT          ○ : FLASHING LIGHT                X : OFF            Flash cycle is 1 second

Error Code Running Timer Sleep Power Issue Cause may be one of the following:
1 2 3 4
0 Normal
Operation
1 X ○ X X Outdoor coil temperature sensor failure
  • Outdoor temperature sensor connection is loose
  • Outdoor temperature sensor failure
  • Indoor control board failure
2 X ○ ★ X Compressor exhaust temperature sensor issue
  • Compressor exhaust temperature sensor connection is loose
  • Compressor exhaust temperature sensor failure
  • Outdoor control board failure
5 ★ ○ X X IPM module protection
  • IPM board failure
  • Outdoor unit fan is broken
  • Outdoor unit fan motor failure
  • Outdoor unit fan motor is blocked
  • Condenser is dirty
  • Outdoor unit not installed properly
6 ★ ○ X ★ AC voltage out of range protection
  • Supplied voltage is higher or lower than normal
  • Indoor unit supply voltage is higher or lower than normal
7 ★ ○ ★ X Communication failure between Indoor Unit and Outdoor Unit
  • Communication cable connection is loose
  • Communication cable failure
  • Connection between the filter board and the outdoor control board is incorrect or loose
  • Connection between the filter board and the terminal is incorrect or loose
  • Indoor control board failure
  • PFC board failure
  • Power board failure
  • Outdoor control board failure
8 ★ ○ ★ ★ Current overload protection
  • Fan motor is running abnormally
  • Condenser and evaporator are dirty
  • Air inlet and/or outlet is abnormal
9 X X ○ X Maximum current protection
  • Outdoor control board has a short circuit
  • Drive board has a short circuit
  • Other component has a short circuit
10 X X ○ ★ Communication issue between Outdoor unit and driver
  • Connection wires connection loose
  • Outdoor board or drive board failure
11 X ★ ○ X Outdoor EEPROM issue
  • EEPROM chip is loose
  • EEPROM chip installed backwards
  • EEPROM chip failure
12 X ★ ○ ★ Outdoor ambient temperature too low
  • Outdoor ambient temperature is too low
13 ★ X ○ X Compressor exhaust temperature too high protection
  • Compressor exhaust temperature sensor failure
  • Refrigerant level is low
14 ★ X ○ ★ Outdoor ambient temperature sensor
issue
  • Outdoor ambient temperature sensor connection is loose
  • Outdoor ambient temperature sensor failure
  • Outdoor control board failure
15 ★ ★ ○ X Compressor shell temperature too high protection
  • Compressor exhaust temperature sensor connection is loose
  • Refrigerant level is low
16 Anti-freeze protection during cooling, or overload protection during heating
  • Indoor coil temperature sensor connection is loose
  • Indoor coil temperature sensor failure
  • Indoor control board failure
  • Refrigerant system is abnormal
17 PFC protection
  • PFC failure
  • Outdoor drive board failure
18 DC compressor start failure
  • Outdoor drive board failure
  • Compressor failure
19 X X X ○ Compressor drive issue
  • Outdoor drive board failure
  • Compressor failure
  • Outdoor control board failure
20 ★ X X ○ Outdoor fan motor-locked rotor protection
  • Outdoor fan motor connection loose
  • Outdoor fan is blocked
  • Outdoor fan is broken
  • Outdoor control board failure
21 Outdoor coil anti-overload protection while cooling
  • Too much refrigerant in system
  • Outdoor fan motor failure
  • Outdoor fan is broken
  • Dirty condenser
  • Air inlet and/or outlet of Indoor unit and/or Outdoor unit are abnormal
22 Compressor preheating process
  • This is a normal function of the unit during cold weather
24 Outdoor board chip issue
  • Incorrect drive board installed
  • Incorrect compressor installed
26 Outdoor unit radiator overheated
  • Radiator sensor failure
  • Control panel detection circuit on the sensor failure
27 High system pressure protection
  • Pressure switch failure
  • Pressure detection switch on the control panel failure
  • Measured system pressure exceeds system limit
33 ○ X X ★ Indoor unit temperature sensor failure
  • Indoor unit temperature sensor is loose
  • Indoor unit temperature sensor failure
34 ○ X ★ X Indoor unit coil temperature sensor failure
  • Indoor coil temperature sensor is loose
  • Indoor coil temperature sensor failure
  • Indoor control board failure
36 ○ ★ X ★ Communication failure between Indoor unit and Outdoor unit
  • Communication cable is loose
  • Communication cable has failed
  • Connection between filter board and Outdoor unit control board is incorrect or loose
  • Connection between filter board and terminal is incorrect or loose
38 ○ ★ ★ ★ Indoor
EEPROM failure
  • EEPROM chip is loose
  • Indoor control board failure
39 ○ X ★ ★ Indoor fan motor running abnormally
  • Fan motor is blocked
  • Fan motor cord connection is loose
  • Fan motor failure
  • Indoor control board failure
41 ★ ★ ○ ★ Indoor grounding protection failure
  • Indoor control board failure

 

 

LED Display

Key:     ★ : LIGHT          ○ : FLASHING LIGHT                X : OFF            Flash cycle is 1 second

Error Code Sleep Timer Running Issue Cause may be one of the following:
1 2 3
0 Normal Operation
1 ○ ★ ★ Outdoor coil temperature sensor failure
  • Outdoor temperature sensor loose
  • Outdoor temperature sensor failure
  • Indoor control board failure
2 Compressor exhaust temperature sensor issue
  • Compressor exhaust temperature sensor is loose
  • Compressor exhaust temperature sensor failure
  • Outdoor control board failure
5 ★ ○ X IPM module protection
  • IPM board failure
  • Outdoor fan is broken
  • Outdoor fan motor failure
  • Outdoor fan is blocked
  • Dirty condenser
  • Outdoor unit has been installed incorrectly
6 X ○ X AC voltage high or low protection
  • Supplied voltage is higher or lower than normal
  • Internal supplied voltage of the unit is higher or lower than normal
7 ★ ★ X Communication failure between Indoor unit and Outdoor unit
  • Communication cable is loose
  • Communication cable failure
  • Connection between filter board and outdoor control board is incorrect or loose
  • Connection between the filter board and terminal is incorrect or loose
  • PFC board failure
  • Power board failure
  • Outdoor control board failure
8 Current overload protection
  • Fan motor is running abnormally
  • Dirty condenser and evaporator
  • Air inlet and/or outlet is abnormal
9 Maximum current protection
  • Outdoor control board has a short circuit
  • Drive board has short circuit
  • Another component has a short circuit
10 ★ X X Communication issue between Outdoor unit and driver
  • Connection wires connection loose
  • Outdoor board or drive board failure
11 ○ X X Outdoor EEPROM issue
  • EEPROM chip is loose
  • EEPROM chip is installed backwards
  • EEPROM chip failure
12 Low outdoor ambient temperature protection
  • Outdoor ambient temperature is below system operation range
13 ○ X ★ High compressor exhaust temperature protection
  • Compressor exhaust temperature sensor failure
  • System refrigerant level is low
14 ★ ★ ○ Outdoor ambient temperature sensor issue
  • Outdoor ambient temperature sensor is loose
  • Outdoor ambient temperature sensor failure
  • Outdoor control board failure
15 X ○ ★ High compressor shell temperature protection
  • Compressor exhaust temperature sensor connection loose
  • System refrigerant level is low
16 ★ X ★ Anti-freeze protection in cooling, or overload protection in heating
  • Indoor coil temperature sensor is loose
  • Indoor coil temperature sensor failure
  • Indoor control board failure
  • Refrigerant system is abnormal
17 X ★ X PFC protection
  • PFC failure
  • Outdoor drive board failure
18 X ★ ★ DC compressor start failure
  • Outdoor drive board failure
  • Compressor failure
19 X ★ ○ Compressor drive issue
  • Outdoor drive board failure
  • Compressor failure
  • Outdoor control board failure
20 ★ X ○ Outdoor fan motor locked rotor protection
  • Connection of outdoor fan motor is loose
  • Outdoor fan motor blocked
  • Fan motor failure
  • Outdoor control board failure
21 X X ○ Outdoor coil anti-overload protection while cooling
  • Too much refrigerant in the system
  • Outdoor fan motor failure
  • Outdoor fan is broken
  • Dirty condenser
  • Air inlet and/or air outlet of the indoor unit and/or the outdoor unit is abnormal
22 Compressor preheating protection
  • This is a normal mode of operation in cold weather
24 Outdoor board chip issue
  • Incorrect drive board is installed
  • Incorrect compressor is installed
26 Outdoor radiator overheated
  • Radiator sensor failure
  • Detection circuit of the sensor on the control panel failure
27 High system pressure protection
  • Pressure switch failure
  • Pressure detection switch on control board failure
  • Measured value of system pressure exceeds system pressure limit
33 ★ ○ ○ Indoor temperature sensor failure
  • Indoor temperature sensor is loose
  • Indoor temperature sensor failure
  • Indoor control board failure
36 ○ ★ ○ Communication failure between indoor and outdoor unit
  • Communication cable is loose
  • Communication cable failure
  • Connection between the filter board and outdoor control board is incorrect or loose
  • Connection between the filter board and terminal is incorrect or loose
  • Indoor control board failure
  • Power board failure
  • Outdoor control board failure
38 ○ ○ X Indoor EEPROM failure
  • EEPROM chip is loose
  • Indoor control board failure
39 ○ ○ ★ Indoor fan motor running abnormally
  • Indoor fan motor is blocked
  • Fan motor cord connection is loose
  • Fan motor failure
  • Indoor control board failure
41 X X ★ Indoor ground protection failure
  • Indoor control board failure

 

A room temperature sensor failure is displayed if the sensor does not respond for over 5 seconds.

A heat exchange temperature sensor failure is displayed if the sensor does not respond for over 5 seconds.

A failure is displayed when the settings data does not match after the EEPROM self-checks two times.

A ground signal failure is displayed if the signal is not detected after the air conditioning system is powered ON.

M2 Single and Dual Zone 13/14 SEER Systems Error Codes

Protection/ Error Codes Description Possible Reasons Suggestion for User Technician Trouble-Shooting
E1 Condensate Full in drain pan
  • Drain pan dirty
  • Drain hose clogged
  • Water level switch failure
  • Loose connection
  • Bad control board/ components
  • Check  drain hose to see if it is clogged.
  • If drain hose does not appear clogged, contact your installer or service technician.
  1. Shut off power
  2. Check one by one, each of the possible issues listed at left.
  3. For a quick diagnosis, we suggest your technician makes an appointment with one of our YMGI technical support agents, and calls us while at the job site.
  4. To help speed up support, check the unit, and please have the model number, and serial number ready of the unit(s) being serviced ready, and the suspected unit problem, before contacting YMGI technical support.
  5. HVAC Technician needs to be physically at the job site, use right tools and be experienced to find all the possible causes to correct or fix the issues.
E2 Indoor air temp. sensor failure
  • Bad temperature sensor
  • Loose connection
  • Damaged wires
  • Bad control board/components
  • Lift up grille/cover to check if the sensor looks bad or drops out of holding socket/ pocket
  • Call your installer or service technician.
E3 Indoor coil copper tube sensor failure
  • Bad temperature sensor
  • Loose connection
  • Damaged wires
  • Bad control board/components
E4 Abnormal cooling
  • Dirty filters/coils, refrigerant leaks over time
  • Pipe too long
  • Kinks or clogging in pipe line or valves
  • Pipe damage
  • Sensor failure
  • Compressor or board or other component failures, etc.
  1. Regularly check and clean indoor unit filters, indoor and outdoor coils.
  2. The service valves at outdoor unit should be generally cool in cooling mode, hot in heating mode.
  3. Call your installer or service technician to examine unit.
E5 Abnormal heating
E6 Cooling-outdoor coil low temp. protection
  • Outdoor too cold to run cooling mode
  • Windy
  • Too much refrigerant
  • Short piping
  1. Shut off the unit
  2. Cooling: wait until weather allows the unit to re-start, or switch to alternative cooling equipment which allows lower ambient cooling
  3. Heating: wait until weather allows the unit to re-start, or switch to base-board heater, gas furnace or other alternative heating sources during cold hours/days.
  1. Check if these are caused by installation or component failure
  2. In some instances, there may be nothing abnormal. The unit may have entered a protection mode, which means the current ambient temperature is outside the systems operating range.
  3. If there is a problem, you may need to do a full diagnostic to find all the causes and correct or repair the problem.
E7 Cooling-Indoor coil anti-freeze protection
  • Dirty filter/coils, indoor fan motor failure
  • Loose blower wheel/motor connection
  • Too much or less  refrigerant
  • Pipe/cap. tube/valve clogging
E8 Heating-outdoor coil high temperature protection
  • Outdoor temperature too warm to run heating mode
  • Too much refrigerant
  • Short piping
E9 Heating-indoor coil anti-over heat protection
  • Dirty filter/coils, indoor fan motor failure
  • Loose blower wheel/motor connection
  • Too much refrigerant
  • Pipe/cap. tube/valve clogging
E0 Heating-outdoor coil too cold protection
  • Outdoor temperature is too cold to run heat pump/heating.

M3 Single Zone 13 SEER Systems Error Codes

 Protection/ Error Code Error Code – Light Signal Error Indicated Trouble Shooting
F4 SLEEP & TIME light blink Over-current protection Check for abnomalities in the incoming power voltages, wire sizing/connections, system refrigerant charge level, vacuum level, restrictions etc.
F5 WARM, SLEEP & TIME lights solid EEPROM read error Check wire connections. Shut off power, wait 30 seconds and restore power.
F6 POWER, TIME light blink, SLEEP light solid PG motor error Check and debug the PG motor, its driving circuit, or feedback control circuit
F7 POWER, SLEEP lights blink & TIME light solid RT indoor air temperature sensor error Chech sensor wire continuity, sensor resistance and installation
F8 POWER, TIME & SLEEP light blink PT indoor coil pipe temperature sensor error Check sensor wire continuity, sensor resistance and installation
F9 POWER & SLEEP light blink OT outdoor coil pipe termperature sensor error Check sensor wire continuity, sensor resistance and installation

M1 16 SEER (57)2,3 Systems

Fault Code Display Table.

Check parts Serial number Malfunction content Indoor unit display status Code
Indoor parts 1 The communication faults in the indoor and outdoor units F1
2 Indoor ambient temp. sensor fault F2
3 Indoor coil temperature sensor fault (Includes: Inlet, middle of pipe, outlet.) F3
4 Indoor fan fault F4
Outdoor parts 1 Outdoor module fault F5
2 Outdoor ambient temp. sensor fault F6
3 Outdoor coil temp. sensor fault F7
4 Compressor discharge temp. sensor
fault		 F9
5 Compressor drive abnormal fault FC
6 Phase lacking or phase sequence
fault		 FD
7 Outdoor DC Motor FH

Note:
The above error code information is applicable to several models of air conditioners, but because of product changes or improvements, they can change. Please refer to the User’s Manual for more information, or have a technician contact YMGI.

Protection Display Table.

Check parts Serial number Protection content Indoor unit display status  Code
Indoor parts 1 Evaporator temp protection P1
Outdoor parts 1 Overheat, over current protection of inverter module P2
2 Over current protection P3
3 Compressor discharging temp. protection P4
4 Overheat of compressor top protection P5
6 Power supply over current/over voltage protection P7
9 High temp of condenser protection PA
10 High temp of outdoor ambient protection PC


M1 Single Zone 13 SEER Systems

Protection/ Error Code Self-Check code of Running Lamp Error Indicated
“dF” or Heating Icon blinks Blinks 1 time/sec Defrost Indication
Fan Motor Icon not Lit Blinks 1 time/ sec Anti-cold Wind
E2 Blinks 1 time/ 8 sec Room Temperature Sensor fault
E3 Blinks 2 times / 8 sec Coil Temperature Sensor
E8 Blinks 3 times / 8 sec Overheat Protection/Defrosting
E5 Blinks 6 times / 8 sec Indoor Fan Fault
E7 Blinks 7 times / 8 sec External Feedback Fault
E0 Blinks 3 times / 8 sec Open Door Fault
E1 Blinks 4 times / 8 sec Outdoor Tube Temperature Sensor Fault
E6 Blinks 6 times / 8 sec (EEPROM) Communication Failure(s)
FF Blinks 1 time / sec Outdoor Temperature Exceeds Operating Limits of System.

M1 48 Series Systems

LED Running Lamp
(blink no. times)		 Error The reason of fault and solution
F1 1 communication fault
  1. Check whether the connection of the outdoor unit and indoor unit is one to one, otherwise connect the L, N and communication line of the indoor unit and outdoor unit one to one.
  2. Measure whether the voltage between the zero line and the communication line is 18V-30AC half-wave signal, check whether the communication circuit on the indoor and outdoor electric control board has been damaged, otherwise replace it.
  3. Check whether the LED on the outdoor power board has been on, otherwise replace the electric control board.
  4. Check whether the unit is abnormal caused by the external interference, if it is, then find the interfering source, and removes it.
F2 2 ambient temp.
sensor fault
  1. Check whether the resistance of sensor is normal, otherwise replace it.
  2. Check whether the sensor wire is short circuit or open circuit, and whether the plug is well contacted, whether there is welding off or rosin joint on the electric control board, repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or integrated circuit is damaged, the electric control board should be replaced.
F3 3 coil pipe temp.
sensor of indoor
unit
fault(inlet,middle,outlet)
  1. Check whether the resistance of sensor is normal, otherwise replace it.
  2. Check whether the sensor wire is short circuit or open circuit, and whether the plug is well contacted, whether there is welding off or rosin joint on the electric control board, repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or integrated circuit is damaged, the electric control board should be replaced.
F4 4 fan motor of indoor
  1. Check whether the contact of the plug of the motor wire unit fault and socket is well, making sure well contact.
  2. Check whether the indoor motor has damaged, the motor should be replaced when it is damaged.
  3. Check whether the controllable silicon and other components on the electric control board have damaged, replace the controllable silicon or electric control board when they are damaged.
F5 5 module of outdoor
unit fault
  1. Check whether the connection of the compressor is reliable, otherwise connect firmly again.
  2. Check whether the fixation between the IPM module and the radiator is firm.
  3. Check whether the compressor is well, otherwise replace it.
  4. Check whether the IPM module is abnormal, otherwise replace it.
F6 6 ambient temp.
sensor of outdoor
fault
  1. Check whether the resistance of sensor is normal, otherwise replace it.
  2. Check whether the sensor wire is short circuit or open circuit, and whether the plug is well contacted, whether there is welding off or rosin joint on the electric control board, repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or integrated circuit is damaged, the electric control board should be replaced.
F7 7 coil pipe temp.
sensor of outdoor
unit fault
  1. Check whether the resistance of sensor is normal, otherwise replace it.
  2. Check whether the sensor wire is short circuit or open circuit, and whether the plug is well contacted, whether there is welding off or rosin joint on the electric control board, repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or integrated circuit is damaged, the electric control board should be replaced.
F8 8 suction temp.
sensor of
compressor fault
  1. Check whether the resistance of sensor is normal. If not,  replace it.
  2. Check whether the sensor wire is short circuit or open circuit, and whether the plug is well contacted, whether there is welding off or rosin joint on the electric control board, repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or integrated circuit is damaged, the electric control board should be replaced.
F9 9 discharge temp.
sensor of
compressor fault
  1. Check whether the resistance of sensor is normal, otherwise replace it.
  2. Check whether the sensor wire is short circuit or open circuit, and whether the plug is well contacted, whether there is welding off or rosin joint on the electric control 9 board, repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or integrated circuit is damaged, the electric control board should be replaced.
FA 10 inductor of current
or voltage fault
  1. Check whether inductor of current or voltage have been damaged, they should be replaced if they are fault.
FC 11 compressor drive
fault
  1. Power on again, and check the operation of the compressor is normal.
  2. Check whether the connection of the compressor is reliable, otherwise repair.
  3. Check whether the components on the electric control board have been damaged, if they are damaged, the components or the electric control board should be replaced.
FD 12 phase lacking or
phase sequence
fault
  1. Check power wire voltage or change two power wires.
FE 13 gas return sensor
fault
(include
A,B,C,D)
  1. Check whether the resistance of sensor is normal, otherwise replace it.
  2. Check whether the sensor wire is short circuit or open circuit, and whether the plug is well contacted, whether there is welding off or rosin joint on the electric control board, repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or integrated circuit is damaged, the electric control board should be replaced.
FF 14 other fault
P1 1 temp. of evaporator
protection
  1. Check whether the filter of indoor unit is too dirty, and it should be cleaned when it is too dirty.
  2. Check whether it has barrier around indoor unit, it should be remove if it has.
  3. Check whether the indoor motor is damaged, it should be replaced motor or electrical control board when it is damaged.
P2 2 overheat, over
current protection
of inverter module
  1. Check whether the fixation between the IPM module and the radiator is firm.
  2. Check whether the compressor is well, otherwise replace it.
  3. Check whether the IPM module is abnormal, otherwise replace it.
P3 3 over current
protection
  1. Check whether the ambient temperature exceeds the operation range for the air conditioner
  2. Check whether the current detection circuit is abnormal, the electric control should be replaced when it is abnormal.
P4 4 discharge temp. of
compressor
  1. Check whether the air condition system and pressure are normal. 10 protection
  2. Check whether the sensor, connecting wire of the sensor and the detection circuit are abnormal.
P5 5 over heat of
compressor top
protection
  1. Check whether the air condition system and pressure are normal.
  2. Check whether the sensor, connecting wire of the sensor and the detection circuit are abnormal.
P6 6 suction temp. of
compressor
protection
  1. Check whether the air condition system and pressure are normal.
  2. Check whether the sensor, connecting wire of the sensor and the detection circuit are abnormal.
P7 7 low or high voltage
protection
  1. Check whether the supply voltage is out of range from 150 to 270V
  2. Check the voltage detection circuit of the IPM base board is abnormal, if it is abnormal, the IPM base board or the electric control board should be replaced.
P8 8 low presser of gas
return protection
  1. Check whether the pressure is normal when the unit is running. If it is abnormal, check for leakage and welding, add refrigerant.
P9 9 high pressure of
discharge
protection
  1. Check whether the pressure is normal when the unit is running, if it is abnormal, should detect the leakage and welding, add refrigerant.
PA 10 high temp. of
condenser
protection
  1. Check whether the condenser of outdoor unit is too dirty, and it should be cleaned when it is too dirty.
  2. Check whether it is running at bad condition long time.
  3. Check whether senor and wire are normal.
PC 11 high temp. of
outdoor ambient
protection
  1. Check the outdoor ambient temperature is too high or there is heat source around the outdoor unit.
  2. Check whether the sensor and sensor wire are normal.
PF 12 other protection

M1 46 Series Systems

LED failure The reason of fault and solution
F1 communication fault
  1. Check  the connection of the outdoor unit and indoor unit. Make sure the wires are connected to the correct terminals.
  2. Check for  external interference. Make sure nothing is disrupting the communication wires, and that the wiring is not damaged.  If it is, then find the interfering source, and remove it.
  3. Check whether the electrical control board is damaged. If damaged, it should be replaced.
F2 indoor temp. sensor fault
  1. Check whether the resistance of sensor is normal, otherwise replace it.
  2. Check whether the sensor wire is short circuited or if there is an open circuit, make sure the plug is well connected. Check to see if there is any soldering that has come off or rosin joint on the electric control board. Repair it if there is any of the above.
  3. When the 1 and 2 are both normal, then the components or integrated circuit could be damaged. The electric control board should be replaced.
F3 outlet e temp. sensor of indoor unit coil pipe fault
  1. Check whether the resistance of sensor is functioning normally,. If not, replace it.
  2. Check whether the sensor wire is short circuited or an open circuit, and whether the plug is well connected. Also check to see whether there is soldering that has come off or a rosin joint on the electric control board. Repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or
    integrated circuit is damaged. The electric control board should be replaced.
F3 suction temp. sensor of indoor
unit coil pipe fault
  1. Check whether the resistance of sensor is normal, otherwise replace it.
  2. Check whether the sensor wire is short circuited or an open circuit, and whether the plug is well contacted, whether there is soldering off or rosin joint on the electric control board. Repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or
    integrated circuit is damaged. The electric control board should be replaced.
F3 middle temp. sensor of indoor unit coil pipe fault
  1. Check whether the resistance of sensor is normal, otherwise replace it.
  2. Check whether the sensor wire is short circuited or an open circuit, and whether the plug is well connected, whether there is soldering off or rosin joint on the electric control board, repair it if there is any above.
  3. When the 1 and 2 are both normal, then the components or
    integrated circuit is damaged. The electric control board should be replaced.
F4 PG motor fault
  1. Check whether the contact of the plug of the motor wire and socket is well, making sure well contact.
  2. Check whether the indoor motor has damaged, the motor should be replaced when it is damaged.
  3. Check whether the controllable silicon and other components on the electric control board have damaged, replace the controllable
    silicon or electric control board when they are damaged.
P2 protection of module fault
  1. Check whether the connection of the compressor is reliable, otherwise connect firmly again.
  2. Check whether the fixation between the IPM module and the radiator is firm.
  3. Check whether the compressor is well, otherwise replace it.
  4. Check whether the IPM module is abnormal, otherwise replace it.
P3 over current of outdoor unit
  1. Check whether the ambient temperature exceeds the operation range for the air conditioner
  2. Check whether the current detection circuit is abnormal, the electric control should be replaced when it is abnormal.
P4 discharge temp. of compressor too high, outside ambient temp. too high, temp. switch of compressor crust cut off, temp. of module too high.
  1. Check whether the pressure is normal when the unit is running, if it is abnormal, should detect the leakage and welding, add
    refrigerant.
  2. Check whether ambient temp. is too high or too low, when
    the temp. more than -20 degree and less 55 degree, it can
    disappear automatically.
  3. communicate interference, earth wire and communicate wire can’t put in one cable.
  4. Check whether temp. switch of compressor is damage, it
    should be replace if it damaged.
P7 DC voltage abnormal of outdoor unit
  1. Check whether the supply voltage is out of rang from 150 to 270V
  2. Check the voltage detection circuit of the IPM base board is
    abnormal, if it is abnormal, the IPM base board or the electric
    control board should be replaced.
P8 lack refrigerant or reverse valve fault
  1. Check whether the high and low pressure valves have been opened, otherwise open the valves.
  2. Check whether the indoor coil pipe temperature sensor is normal, if it is abnormal, the sensor should be replaced.
  3. Check the system pressure is abnormal, if it is abnormal, should
    detect leakage repairing welding and adding the refrigerant.
F6 outside sensor fault
  1. Mode Clash. Check to see that both Indoor units are set to the same mode. Both should be in Heating mode or cooling mode. If they are set to auto, this can cause conflict if one room is attempting to heat and the other is attempting to cool.
  2. Check whether the resistance of sensor is normal, otherwise replace it.
  3. Check whether the sensor wire is short circuit or open circuit, and whether the plug is well contacted, whether there is welding off or rosin joint on the electric control board, repair it if there is any above.
  4. When the 1 and 2 are both normal, then the components or
    integrated circuit is damaged, the electric control board should be replaced.
FC outdoor unit drive fault, start compressor failure
  1. Power on again, and check the operation of the compressor is
    normal.
  2. Check whether the connection of the compressor is reliable,
    otherwise repair.
  3. Check whether the components on the electric control board have been damaged, if they are damaged, the components or the electric control board should be replaced.

PTAC Systems

Malfunction Possible Causes
Indoor ambient temperature sensor is open/short circuited
  1. The wiring terminal between indoor ambient temperature controller is loosened or has poor contact
  2. There is a short circuit due to the trip-over of the parts on the controller
  3. Indoor ambient temperature sensor is damaged (Please check it by referring to the resistance table for temperature sensor)
  4. Main board is broken
Indoor evaporator temperature sensor is open/short circuited
  1. The wiring terminal between the indoor evaporator temperature sensor and controller is loose or has poor contact
  2. There’s a short circuit due to trip-over of the parts on the controller
  3. Indoor evaporator temperature sensor is damaged
  4. Main board is broken
Outdoor ambient temperature sensor is open/short circuited
  1. The wiring terminal between the outdoor ambient temperature sensor and controller is loose or has poor contact
  2. There’s a short circuit due to trip-over of the parts on the controller
  3. Outdoor ambient temperature sensor is damaged. (Please check it by referring to the resistance table for temperature sensor)
  4. Main board is broken
Low temperature prevention protection
  1. Indoor ambient temperature is lower than 40 °F (5 °C) continuously
  2. Indoor ambient temperature sensor is damaged
  3. Main board is broken

PTAC Series 0 Error Codes

Protective Auto Diagnostics

Failure code Content of defect
E2 Indoor temperature sensor failure
E3 Indoor coil temperature sensor failure
E4 High temperature protection of air outlet
E5 Outdoor coil temperature sensor failure
E8 Overheating protection/defrosting
E9 High temperature protection of outdoor coil

TABLE OF ERROR CODES FOR OUTDOOR UNIT

Error Code Content
E0 Outdoor Unit Error
E1 High Pressure Protection
E2 Discharge Low Temperature Protection
E3 Low Pressure Protection
E4 Excess Discharge Temperature Protection of Compressor
Ed Low Refrigerant Protection
EN Copressor Power Protection
F0 Bad Performance of the Outdoor Mainboard
F1 High Pressure Sensor Error
F3 Low Pressure Sensor Error
F5 Compressor 1 Discharge Temperature Sensor
F6 Compressor 2 Discharge Temperature Sensor Error
F7 Compressor 3 Discharge Temperature Sensor Error
F8 Compressor 4 Discharge Temperature Sensor Error
F9 Compressor 5 Discharge Temperature Sensor Error
FA Compressor 6 Discharge Temperature Sensor Error
Fb Compressor 2 Top Temperature Sensor Error
FC Compressor 2 Current Sensor Error
Fd Mode Exchanger Outlet Pipe Temperature Sensor Error
FE Compressor 4 Current Sensor Error
FF Compressor 5 Current Sensor Error
FH Compressor 1 Current Sensor Error
FJ Compressor 6 Current Sensor Error
FL Compressor 3 Current Sensor Error
Fn Mode Exchanger Inlet Pipe Temperature Sensor Error
FP Malfunction of DC motor
FU Compressor 2 Top Temperature Sensor Error
J1 Compressor 1 Over-current Protection
J2 Compressor 2 Over-current Protection
J3 Compressor 3 Over-current Protection
J4 Compressor 4 Over-current Protection
J5 Compressor 5 Over-current Protection
J6 Compressor 6 Over-current Protection
J7 4-way Valve Blow-by Protection
J8 System Pressure Over-Ratio Protection
J9 System Pressure Under-Ratio Protection
JA Protection of Abnormal Pressure
JC Protectionof Water Flow Switch
JE Oil return pipe is blocked
JF Oil return pipe is leaking
JL Protection of Low High-pressure
b1 Outdoor Ambient Temperature Sensor Error
b2 Defrosting Temperature Sensor 1 Error
b3 Defrosting Temperature Sensor 2 Error
b4 Subcooler Liquid-out Temperature Sensor Error
b5 Subcooler Gas-out Temperature Sensor Error
b6 Gas-liquid separator inlet temperature sensor error
b7 Gas-liquid separator outlet temperature sensor error
b8 Outdoor Humidity Sensor Error
b9 Heat Exchanger Gas-out Temperature Sensor Error
bA Oil-return Temperature Sensor Error
bC Compressor 1 Top Temperature Sensor Detachment Protection
bE Malfunction of entry tube temperature sensor of condensor
bF Malfunction of exit tube temperature sensor of condenser
bH System Clock Malfunction
bJ High and low pressure sensors are connected inversely
bL Compressor 2 Top Temperature Sensor Detachment Protection
Fd High pressure switch
P0 Compressor Drive Board Error
P1 Compressor Drive Board Malfunction
P2 Protection of Compressor Drive Board Power Supply
P3 Protection of Compressor Drive Board Module Reset
P4 PFC Over current protection
Pn PFC Module Overheat
PE Phase loss protection of compressor
P5 AC over current
P6 IPM over current
P8 IPM module overheat
P9 Desynchronization protection
PH Busbar over voltage protection
PC Phase current detection fault
PL Busbar under voltage protection
PF Capacitor charge error
PU Demagnitization protection
H0 Error of Fan Drive Board
H1 Malfunction of Fan Drive Board
H2 Protection of Fan Drive Board Power Supply
– —

 

 

TABLE OF ERROR CODES FOR INDOOR UNIT

Error Code Content
E0 Low Refrigerant Protection
E0 Copressor Power Protection
EO PFC Over current protection
EO Middel Sensor Error
EO High Pressure Switch
L0 Indoor Unit Error
L1 Indoor Fan Protection
L2 E-heater Protection
L3 Water Full Protection
L4 Wired Controller Power Supply Error
L5 Anti-Frosting Protection
L6 Mode Conflict
L7 No Master Indoor Unit Error
L8 Power Insufficiency Protection
L9 Quantity Of Group Control Indoor Units Setting Error
LA Indoor Units Incompatibility Error
Lb Inconsistency of Group-controlled Indoor Units in Reheat Dehumidification System
LC Outdoor-Indoor Incompatibility Error
LF Shunt Valve Setting Error
LH Low Air Quanlity Warning
LJ Wrong Setting ofFunction DIP Switch
LP Zero-crossing malfunction of PG motor
LU Inconsistent Branch of Group-controlled Indoor Units in Heat Recovery System
d1 Indoor Unit PC-Board Error
d3 Ambient Temperature Sensor Error
d4 Inlet Pipe Temperature Sensor Error
d5 Malfunction of middle tube temperature sensor
d6 Outlet Pipe TemperatureSensor Error
d7 Humidity Sensor Error
d8 Water Temperature Abnormality
d9 Jumper Cap Error
dA Indoor Unit Hardware Address Error
db Special Code:Field Debugging Code
dC Capacity DIP Switch Setting Error
dE Indoor Unit CO2 Sensor Error
dH Wired Controller PC-Board Error
dL Outlet Air Temperature Sensor Error
dn Swing AssemblyError
P0 PFC Module Overheat
P0 Phase loss protection of compressor
P0 AC over current
P0 IPM over current
P0 IPM module overheat
P0 Desynchronization protection
P0 Busbar over voltage protection
P0 Phase current detection fault
P0 Busbar under voltage protection
P0 Capacitor charge error
P0 Demagnitization protection
y7 Fresh Air Inflow Temperature Sensor Error
y8 Indoor Air Box Sensor Error
y9 Outdoor AirBox Sensor Error
– —

 

TABLE OF DEBUGGING CODES

Error Code Content
U2 Outdoor Unit Capacity Code/Jumper Cap Setting Error
U3 Phase Sequence Protection of Power Supply
U4 Protection of Lack of Refrigerant
U5 Wrong Address of Compressor Drive Board
U6 Valve Abnormal Alarm
U8 Indoor Unit Tube Malfunction
U9 Outdoor Unit Tube Malfunction
UC Master indoor unit is successfully set
UE Refrigerant Charging is ineffective
UF Indoor Unit Identification Error of Mode Exchanger
UL Emergency Operation DIP switch setting of the compressor is wrong
C0 Communication between indoor unit and outdoor unit and the communication between indoor unit and wired controller have malfunction
C1 485 Communication Error between main controller and debugging controller
C2 Communication error between master control and inverter compressor drive
C3 Communication error between master control and inverter fan motor drive
C4 Error of Lack of Indoor Unit
C5 Alarm of Indoor Unit Project Number Collision
C6 Alarm of Wrong Number of Outdoor Unit
C7 Mode Exchanger Communication Error
Cb Outflow of Units IPAddress
Cd CommunicationFailure Between Mode Exchanger and Outdoor Unit
CE Communication Failure Between Mode Exchanger and Indoor Unit
CF Error of Multiple Master Indoor Unit
CH Rated capacity is too high.
CJ System addresses is incompatible.
CL Rated capacity is too low.
Cn Indoor and Outdoor NetworkError of Mode Exchanger
CP Error of Multiple Master Wired Controller
CU Communication Error between Indoor Unit and Remote Receiver
Cy CommunicationError of No Master in Mode Exchanger

 

 

TABLE OF STATUS CODES

Error Code Content
A0 Unit is waiting for debugging
A1 Check the compressor operation parameters
A2 After-sales Refrigerant Reclaim
A3 Defrosting
A4 Oil return
A5 Online Testing
A8 Vacuum-pumping Mode
Ab Emergency Stop
Ad Operation Restriction
AC Cooling
AF Fan
AH Heating
AJ Filter Clean Reminder
AU Remote Urgent Stop
n3 Compulsory defrosting
qE EVI Operating Mode

 

SHCR Error Codes

NO. LED1
(GREEN)		 LED2
(RED)		 LED3
(RED)		 Status Trouble Shooting
1 On Off Off Cooling mode – normal operation N/A
2 On On Off Heating mode – normal operation N/A
3 On On On Defrosting mode – ongoing N/A
4 On/On
(AC/HP)		 Off/On
(AC/HP)		 Blinks 3 times/ 5 seconds Outdoor defrost temperature sensor failure Check connectivity or resistance of this sensor, or replace with a new sensor.
5 On Off Blinks 1 times/ 5 seconds Cooling Mode, High Pressure Protection is ON.
The whole unit stops working until the problem is cleared, or power is turned off, and then restored, or another unit function is selected.		 Check possible causes:
Mechanical or refrigerant blockage at the filter/drier.
Too much refrigerant.
4-way valve is damaged.
Faulty TEV or others.
Electrical wiring connection is faulty.
Component is damaged.
Or switch Unit funtion.
6 On Off Blinks 2 times/ 5 seconds Cooling Mode, Low Pressure Protection is ON.
The whole unit stops working until the problem is cleared, or power is turned off, and then restored, or another unit function is selected.		 Check possible causes:
Refrigerant is very low
4-way valve is damaged.
Faulty TEV or others.
Electrical wiring connection is faulty.
Component is damaged.
Or switch Unit funtion.
7 On On Blinks 1 times/ 5 seconds Heating Mode, High Pressure Protection is ON.
The whole unit stops working until the problem is cleared, or power is turned off, and then restored, or another unit function is selected.		 Check possible causes:
Mechanical or refrigerant blockage at the filter/drier.
Too much refrigerant.
4-way valve is damaged.
Faulty TEV or others.
Electrical wiring connection is faulty.
Component is damaged.
Or switch Unit funtion.
8 On On Blinks 2 times/ 5 seconds Heating Mode, Low Pressure Protection is ON.
The whole unit stops working until the problem is cleared, or power is turned off, and then restored, or another unit function is selected.		 Check possible causes:
Refrigerant is very low
4-way valve is damaged.
Faulty TEV or others.
Electrical wiring connection is faulty.
Component is damaged.
Or switch Unit funtion.