Reference
AC Error Codes
Fault code lookups for the UK's most common air conditioning brands. Pick a manufacturer to see codes, likely causes and recommended actions.
Mitsubishi Electric
16 codes
Mr. Slim and City Multi systems display codes on the wired controller or by flashing LEDs on the outdoor PCB.
Mitsubishi Heavy Industries
17 codes
MHI (SRK / FDT / KX) shows E-codes on the wired controller; outdoor LEDs flash a green/red pattern.
Samsung
17 codes
Samsung (AR/AJ/DVM S) shows E1xx / E2xx / E4xx codes on the wired controller or wireless display.
Daikin
20 codes
Daikin splits (FTX/FTXM) and VRV display 2-character codes on the BRC controller or by indoor LED flashes.
Fujitsu
17 codes
Fujitsu (ASYG/AOYG, AirStage VRF) flashes Operation + Timer LEDs; wired controllers show E:EE codes.
LG
20 codes
LG (Multi V, Multi Split, single splits) shows CHxx codes on wired controllers; wireless units flash indoor LEDs.
Midea
18 codes
Midea (and rebadges incl. Comfee, some Bosch/Olimpia) shows E/P/F codes on the wired/wireless controller.
Toshiba
22 codes
Toshiba (RAS / SMMS / SHRM) shows alphanumeric check codes on the wired controller; outdoor PCB has 7-segment display.
Haier
17 codes
Haier (Tundra / Flexis / MRV) shows E/F codes on wired/wireless controllers; outdoor 7-segment shows fault data.
Bosch
17 codes
Bosch Climate units (CL3000i / CL5000i / Multi) share much of the Midea code map; controller shows E/P/F codes.
Hitachi
19 codes
Hitachi RAS / Utopia / Set Free shows numeric alarm codes on the PC-ARFP / PC-ARFG controller and outdoor 7-segment.
Codes are a curated starter set for field guidance. Always confirm against the official service manual for the specific model before committing to a repair.