Viessmann Mini-Split Error Codes

Updated October 16, 2026 · by Aurora Star Tech Inc.

129 Viessmann Mini-Split error codes and diagnostic codes, with causes and troubleshooting steps for each. Select a code, or find your model below.

Homeowner with a ductless mini-split problem? Call (647) 657-2977 or book a service call — licensed technicians across Vaughan and the GTA.

Viessmann Mini-Split error codes list

Code	Meaning	Severity
--	Indoor units mode conflict	Low
AP	Wi-Fi pairing (AP mode)	Low
CL	Filter cleaning reminder / Active Clean	Low
CP	Remote switched off	Low
d1	Demand response signal DR1 received	Low
d2	Demand response signal DR2 received	Low
d3	Demand response signal DR3 received	Low
dE	Demand response input error	Low
dF	Defrost	Low
E-C-O	ECO mode	Low
E1	Indoor / outdoor communication error	High
EC07	Outdoor fan speed out of range	High
EC50	Outdoor temperature sensor fault	Medium
EC51	Outdoor EEPROM error	High
EC52	Condenser coil sensor (T3) fault	Medium
EC53	Outdoor ambient sensor (T4) fault	Medium
EC54	Discharge temperature sensor (TP/T5) fault	Medium
EC55	IPM temperature sensor fault	Medium
EC56	Indoor coil outlet sensor (T2B) fault	Medium
EC57	Refrigerant pipe sensor fault	Medium
EC71	Outdoor fan motor over-current	High
EC72	Outdoor fan motor phase loss	High
EH0A	Indoor EEPROM error	High
EH0b	Indoor PCB to display board communication error	Medium
EH00	Indoor EEPROM error	High
EH02	Zero-crossing signal error	Medium
EH03	Indoor fan speed out of range	High
EH30	Indoor external fan low voltage	Medium
EH31	Indoor external fan over voltage	Medium
Eh60	Room sensor (T1) fault	Medium
Eh61	Indoor coil sensor (T2) fault	Medium
EL0C	Refrigerant leak detected	High
EL01	Indoor / outdoor communication error	High
F0	Current overload protection	High
F1	Outdoor ambient sensor (T4) fault	Medium
F2	Condenser coil sensor (T3) fault	Medium
F3	Discharge sensor (T5) fault	Medium
F4	Outdoor EEPROM error	High
F5	Outdoor fan speed out of control	High
Fb	Vapor injection inlet sensor fault	Medium
FC	Forced cooling	Low
Fd	Vapor injection outlet sensor fault	Medium
FH 0d	Fault - see outdoor unit	Low
FH 0P	AP mode on / no Wi-Fi kit	Low
FL14	Indoor and outdoor units not compatible	Medium
FP	Low-temperature heating (8 C mode)	Low
J0	Outdoor coil overheat in cooling	Medium
J1	Indoor coil temperature protection in heating	Medium
J2	Discharge temperature protection	High
J3	PFC module protection	High
J4	Main board to IPM board communication error	High
J5	High pressure protection	High
J6	Low pressure protection	High
J8	AC voltage protection	High
LC01	Speed limited by condenser temperature	Low
LC02	Speed limited by discharge temperature	Low
LC03	Speed limited by current	Low
LC05	Speed limited by voltage	Low
LC06	IPM high temperature / PFC frequency limit	Medium
LH00	Speed limited by indoor coil temperature	Low
LH07	Speed limited by remote	Low
LL	Controls locked	Low
nA	No fault	Low
nF	Filter replacement reminder	Low
ODU --	Outdoor board standby	Low
ODU 00	Wiring / piping check finished	Low
ODU CE	Automatic wiring / piping check running	Low
ODU E0	Outdoor EEPROM error (outdoor board)	High
ODU E2	Indoor / outdoor communication error (outdoor board)	High
ODU E3	IPM to main board communication error (outdoor board)	High
ODU E4	Outdoor or T2B sensor fault (outdoor board)	Medium
ODU E5	Over or under voltage (outdoor board)	High
ODU E6	PFC module protection (outdoor board)	High
ODU E8	Outdoor fan speed fault (outdoor board)	High
ODU Ed	Adapter / inverter board to main board communication error	High
ODU F1	Zone A coil outlet sensor (T2B-A) fault	Medium
ODU F2	Zone B coil outlet sensor (T2B-B) fault	Medium
ODU F3	Zone C coil outlet sensor (T2B-C) fault	Medium
ODU F4	Zone D coil outlet sensor (T2B-D) fault	Medium
ODU F5	Zone E coil outlet sensor (T2B-E) fault	Medium
ODU F6	Zone F coil outlet sensor (T2B-F) fault	Medium
ODU Hz readout	Compressor running frequency	Low
ODU LC	Low ambient cooling mode	Low
ODU LP	Low outdoor temperature protection (outdoor board)	Low
ODU P0	Compressor top overheat (outdoor board)	High
ODU P1	High pressure protection (outdoor board)	High
ODU P2	Low pressure protection (outdoor board)	High
ODU P3	Current overload (outdoor board)	High
ODU P4	Discharge temperature protection (outdoor board)	High
ODU P5	Condenser high temperature (outdoor board)	Medium
ODU P6	Inverter module (IPM) fault (outdoor board)	Critical
ODU PH	Compressor pre-heat	Low
ODU RO	Oil return cycle	Low
Off	Timer off	Low
On	Timer on	Low
P0	Inverter module (IPM) fault	Critical
P1	Over or under voltage protection	High
P2	Compressor top overheat (OLP)	High
P3	Low outdoor temperature cut-off in heating	Low
P4	Compressor drive fault	High
P7	IPM temperature sensor fault	Medium
PC0A	Condenser high temperature protection	Medium
PC0F	PFC module protection	High
PC0L	Outdoor temperature too low	Low
PC00	Inverter module (IPM) protection	Critical
PC02	Compressor top overheat (OLP)	High
PC03	Pressure protection	High
PC04	Inverter compressor drive error	High
PC06	Discharge temperature protection	High
PC08	Outdoor over-current protection	High
PC10	Low AC supply voltage	High
PC11	AC supply voltage protection (over voltage)	High
PC12	DC bus high voltage / 341 MCE error	High
PC30	High pressure protection	High
PC31	Low pressure protection	High
PC40	Main chip to compressor drive chip communication error	High
PC41	Current input detection protection	Medium
PC42	Compressor start failure	High
PC43	Compressor phase loss	High
PC44	Zero speed protection	High
PC45	Compressor drive chip (IR / 341 PWM) failure	High
PC46	Compressor speed out of control	High
PC49	Compressor over-current	High
PCA1	Refrigerant pipe condensation protection	Low
PH09	Anti-cold-air in heating	Low
PH90	Evaporator coil too hot	Medium
PH91	Evaporator coil too cold	Medium
SC	Self clean running	Low
SD	Power abnormal detection	Low

Find codes by Viessmann model

Viessmann Vitocal 200-S DLCM(R/H)B multi-zone outdoor

DLCMHBH24CAK DLCMHBH30DAK DLCMHBH36DAK DLCMHBH48EAK DLCMRBH18BAK DLCMRBH36DAK DLCMRBH48EAK

Viessmann DLFSHB high wall indoor

DLFSHBH09XAK DLFSHBH12XAJ DLFSHBH12XAK DLFSHBH18XAK DLFSHBH24XAK

Mini-Split troubleshooting guides

Indoor unit leaking water All brands · Mini-Split
Poor capacity / high head All brands · Mini-Split
Water leaking All brands · Mini-Split
Discharge the inverter capacitors before service Viessmann · Mini-Split
Display shows a strange code or does not answer the remote - DLFSHB indoor Viessmann · Mini-Split
Multi-zone: one room heats, another will not cool - DLC multi-zone Viessmann · Mini-Split
Read live data with the outdoor check button (SW1) Viessmann · Mini-Split
Run the automatic wiring / piping correction Viessmann · Mini-Split

Homeowner help: AC Running But Not Cooling: What to Check · Heat Pump Not Heating or Blowing Cold Air

General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.