Baxi · An established brand in the UK. 265 codes across 5 product families, each taken from the manufacturer’s manuals. Baxi technical support ↗
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265 codes
| Code | Meaning | Stops? | Homeowner check? |
|---|---|---|---|
| A00.32 | TOutside Open Outside temperature sensor is either removed or measures a temperature below range | No | Yes |
| A00.33 | TOutside Closed Outside temperature sensor is either shorted or measures a temperature above range | No | Yes |
| A00.34 | TOutside Missing Outside temperature sensor was expected but not detected | No | Yes |
| A1 | Display reads A1 with audible alarm | Not stated | Yes |
| A02.06 | Water Press Warning Water Pressure Warning active | No | Yes |
| A02.18 | OBD Error Object Dictionary Error | No | Yes |
| A02.22 | System flow warning System water flow warning active | No | Yes |
| A02.37 | Uncritic device lost Uncritical device has been disconnected: | No | Yes |
| A02.55 | Inval or miss SerNR Invalid or missing device serial number | No | Yes |
| A02.80 | Missing Cascade Ctrl Missing Cascade controller | No | Yes |
| A06.111 | HP unit failure Heat Pump unit failure occurred | No | Yes |
| A06.112 | HP EEPROM error Hydronic system EEPROM error in the heat pump module | No | Yes |
| A06.113 | HP frost protection Water side heat exchanger frost protection | No | Yes |
| A06.114 | HP flow Temp error Flow temperature sensor error in the heat pump module | No | Yes |
| A06.115 | HP EEPROM error Heat pump inverter module EEPROM error | No | Yes |
| A06.116 | Water flow error Water flow is not detected by the heat pump module | No | Yes |
| A06.117 | ODU backup error Electric heating plate relay adhesion failure in the internal backup heater PCB | No | Yes |
| A06.118 | ODU current error Current transformer error or internal backup heater open circuit protection | No | Yes |
| A10.45 | RoomTempZoneA miss Measure of Room Temperature Zone A is missing | No | Yes |
| A10.46 | RoomTempZoneB miss Measure of Room Temperature Zone B is missing | No | Yes |
| A10.47 | RoomTempZoneC miss Measure of Room Temperature Zone C is missing | No | Yes |
| A10.50 | T_DHW top D miss Domestic Hot Water temperature sensor top zone DHW is missing | No | Yes |
| A10.54 | Temp. Zone DHW miss. Temperature sensor Zone DHW is missing | No | Yes |
| A10.56 | T_DHW Zone AUX miss Domestic Hot Water temperature sensor Zone AUX is missing | No | Yes |
| bA | T4 sensor out of operation range protection | No | Yes |
| bH | PED PCB failure | Yes | Yes |
| C7 | Transducer module temperature too high protection | Yes | Yes |
| CL | Water pump communication wire fault | Not stated | Yes |
| E0 | Flow switch error (E8 displayed 3 times) | Yes | Yes |
| E00.00 | TFlow Open Flow temperature sensor is either removed or measures a temperature below range | Yes | Yes |
| E00.01 | TFlow Closed Flow temperature sensor is either shorted or measures a temperature above range | Yes | Yes |
| E1 | Phase sequence fault (three-phase unit only) | Not stated | Yes |
| E2 | Communication error between user interface and main control board of hydraulic module | Not stated | Yes |
| E02.13 | Blocking Input Blocking Input of the Control Unit from device external environment | Yes | Yes |
| E02.24 | System flow locking System water flow locking active | Yes | Yes |
| E3 | Backup heater exchanger outlet water temperature sensor (T1) error | Not stated | Yes |
| E4 | Domestic hot water temperature sensor (T5) error | Not stated | Yes |
| E5 | Condenser outlet refrigerant temperature sensor (T3) error | Not stated | Yes |
| E6 | Ambient temperature sensor (T4) error | Not stated | Yes |
| E06.03 | Locking HydrauBackup Locking Hydraulic Backup | Yes | Yes |
| E06.110 | HP flow error Water flow error active in the heat pump module | Yes | Yes |
| E7 | Buffer tank up temp. sensor (Tbt1) fault | Not stated | Yes |
| E8 | Water flow failure | Not stated | Yes |
| E9 | Suction temperature sensor (Th) error | Not stated | Yes |
| EA | Discharge temperature sensor (Tp) error | Not stated | Yes |
| Eb | Solar temp. sensor (Tsolar) fault | Not stated | Yes |
| Ec | Buffer tank low temp. sensor (Tbt2) fault | Not stated | Yes |
| Ed | Inlet water temperature sensor (Tw_in) error | Not stated | Yes |
| EE | Main control board of hydraulic module EEprom failure | Not stated | Yes |
| EL | Communication fault between hydraulic module and MH kit | Not stated | Yes |
| F1 | DC generatrix (DC bus) voltage too low | Yes | Yes |
| F6 | EXV (electronic expansion valve) fault | Not stated | Yes |
| F75 | Insufficient discharge superheating | Not stated | Yes |
| FC1 | TL outdoor unit heat exchanger outlet temperature sensor error | Not stated | Yes |
| H0 | Communication error between main control board PCB B and main control board of hydraulic module | Not stated | Yes |
| H00.16 | DHW sensor Open Domestic Hot Water tank temperature sensor is either removed or measures a temperature below range | Partly | Yes |
| H00.17 | DHW sensor Closed Domestic Hot Water tank temperature sensor is either shorted or measures a temperature above range | Partly | Yes |
| H00.32 | TOutside Open Outside temperature sensor is either removed or measures a temperature below range | Partly | Yes |
| H00.33 | TOutside Closed Outside temperature sensor is either shorted or measures a temperature above range | Partly | Yes |
| H00.34 | TOutside Missing Outside temperature sensor was expected but not detected | Partly | Yes |
| H00.47 | HP flow sensor removed or below range | Partly | Yes |
| H00.48 | THp Flow Closed Heat pump flow temperature sensor is either shorted or measures a temperature above range | Partly | Yes |
| H00.49 | THp Flow Missing Heat pump flow temperature sensor was expected but not detected | Partly | Yes |
| H00.51 | THp Return Open Heat pump return temperature sensor is either removed or measures a temperature below range | Partly | Yes |
| H00.52 | THp Return Closed Heat pump return temperature sensor is either shorted or measures a temperature above range | Partly | Yes |
| H00.57 | T DHW Top Open Domestic Hot Water top temperature sensor is either removed or measures a temperature below range | Partly | Yes |
| H00.58 | T DHW Top Closed Domestic Hot Water top temperature sensor is either shorted or measures a temperature above range | Partly | Yes |
| H00.69 | TbufferTankOpen Buffer Tank temperature sensor is either removed or measures a temperature below range | Partly | Yes |
| H00.70 | TbufferTankClosed Buffer Tank temperature sensor is either shorted or measures a temperature above range | Partly | Yes |
| H00.71 | TbufferTankTopOpen Buffer Tank top temperature sensor is either removed or measures a temperature below range | Partly | Yes |
| H00.72 | TbufferTankTopClosed Buffer Tank top temperature sensor is either shorted or measures a temperature above range | Partly | Yes |
| H00.74 | TBufferTankMissing Buffer Tank temperature sensor was expected but not detected | Partly | Yes |
| H00.75 | TBufferTankTop Miss Buffer Tank Top temperature sensor was expected but not detected | Partly | Yes |
| H00.76 | TcascadeFlow Open Cascade Flow temperature sensor is either removed or measures a temperature below range | Partly | Yes |
| H00.77 | TcascadeFlow Closed Cascade Flow temperature sensor is either shorted or measures a temperature above range | Partly | Yes |
| H00.78 | TcascadeFlow missing Cascade Flow temperature sensor was expected but not detected | Partly | Yes |
| H1 | Communication error between inverter module PCB A and main control board PCB B | Yes | Yes |
| H2 | Plate heat exchanger refrigerant inlet (liquid pipe) temperature sensor (T2) error | Not stated | Yes |
| H02.02 | Wait Config Number Waiting For Configuration Number | Partly | Yes |
| H02.03 | Conf Error Configuration Error | Partly | Yes |
| H02.04 | Parameter Error Parameter Error | Partly | Yes |
| H02.05 | CSU CU mismatch CSU does not match CU type | Partly | Yes |
| H02.07 | Water Press Error Water Pressure Error active | Partly | Yes |
| H02.09 | Partial block Partial blocking of the device recognized | Partly | Yes |
| H02.10 | Full Block Full blocking of the device recognized | Partly | Yes |
| H02.16 | Int CSU Timeout Internal CSU Timeout | Partly | Yes |
| H02.23 | System flow error System water flow error active | Partly | Yes |
| H02.25 | ACI error Titan Active System short circuited or on an open circuit | Partly | Yes |
| H02.36 | Funct device lost Functional device has been disconnected | Partly | Yes |
| H02.37 | Uncritic device lost Uncritical device has been disconnected | Partly | Yes |
| H02.40 | Function unavailable Function unavailable | Partly | Yes |
| H02.45 | Full Can Conn Matrix Full Can Connection Matrix | Partly | Yes |
| H02.46 | Full Can Device Adm Full Can Device Administration | Partly | Yes |
| H02.47 | Failed Conn Funct Gr Failed Connecting Function Groups | Partly | Yes |
| H02.48 | Funct Gr Conf Fault Function Group Configuration Fault | Partly | Yes |
| H02.49 | Failed Init Node Failed Initialising Node | Partly | Yes |
| H02.55 | Inval or miss SerNR Invalid or missing device serial number | Partly | Yes |
| H02.60 | Unsupported function The zone doesn't support the selected function | Partly | Yes |
| H02.61 | Unsupported function Zone A doesn't support the selected function | Partly | Yes |
| H02.62 | Unsupported function Zone B doesn't support the selected function | Partly | Yes |
| H02.63 | Unsupported function Zone C doesn't support the selected function | Partly | Yes |
| H02.64 | Unsupported function Zone D doesn't support the selected function | Partly | Yes |
| H02.65 | Unsupported function Zone E doesn't support the selected function | Partly | Yes |
| H02.66 | TAS not connected The anti corrosion protection (TAS) of the Domestic Hot Water tank is not connected | Partly | Yes |
| H02.67 | TAS short-circuit The anti corrosion protection (TAS) of the Domestic Hot Water tank is shortend | Partly | Yes |
| H3 | Plate heat exchanger refrigerant outlet (gas pipe) temperature sensor (T2B) error | Not stated | Yes |
| H4 | Three times P6 protection | Yes | Yes |
| H5 | Indoor temperature sensor (Ta) error | Not stated | Yes |
| H6 | DC fan failure | Not stated | Yes |
| H06.01 | HP Unit Failure Heat Pump Unit Failure occured | Partly | Yes |
| H06.06 | BL CompHighPressure A high pressure anomaly has stopped the compressor | Partly | Yes |
| H06.07 | BL CompLowPressure A low pressure anomaly has stopped the compressor | Partly | Yes |
| H06.17 | DeltaT CH max limit The Delta Temperature on the central heating side exceeds the maximum overshoot. | Partly | Yes |
| H06.21 | Tret heat pump Heat pump return temperature sensor error | Partly | Yes |
| H06.22 | Heating error Heating operation error | Partly | Yes |
| H06.23 | Refr pressure Refrigerant pressure sensor error | Partly | Yes |
| H06.24 | Refr high pressure The refrigerant high pressure protection is activated | Partly | Yes |
| H06.25 | Tflow heat pump Heat pump flow temperature sensor error | Partly | Yes |
| H06.26 | HP liquid temp Heat pump liquid temperature sensor error | Partly | Yes |
| H06.27 | Frost protection The heat pump frost protection is activated | Partly | Yes |
| H06.28 | Comm IDU - ODU Communication error between the indoor unit and outdoor unit | Partly | Yes |
| H06.29 | ODU-interface Mismatch between the outdoor unit and the interface board | Partly | Yes |
| H06.30 | ODU temperature The outdoor unit temperature is anomalous | Partly | Yes |
| H06.31 | ODU temp sensor Outdoor unit temperature sensor error | Partly | Yes |
| H06.32 | ODU temp sensor Outdoor unit temperature sensor error | Partly | Yes |
| H06.33 | ODU heatsink temp Outdoor unit heatsink temperature is anomalous | Partly | Yes |
| H06.34 | ODU power module Outdoor unit power module is anomalous | Partly | Yes |
| H06.35 | ODU superheat The outdoor unit superheat is anomalous | Partly | Yes |
| H06.36 | Fan motor Outdoor unit fan motor is anomalous. | Partly | Yes |
| H06.37 | Overheat protection The outdoor unit overheat protection is activated | Partly | Yes |
| H06.38 | ODU pressure The outdoor unit pressure is anomalous | Partly | Yes |
| H06.39 | ODU overcurrent Compressor overcurrent in the outdoor unit | Partly | Yes |
| H06.40 | ODU current sensor Current sensor error in the outdoor unit | Partly | Yes |
| H06.41 | ODU Tinl water The outdoor unit inlet water temperature is anomalous | Partly | Yes |
| H06.42 | ODU refrigerant Outdoor unit refrigerant is anomalous | Partly | Yes |
| H06.43 | DIP switch The DIP switch on the interface board has a configuration error interface panel = EHC–16 PCB | Partly | Yes |
| H06.53 | Tambiant air minimum The ambient air temperature is below the allowed minimum | Partly | Yes |
| H06.58 | HP outdoor temp Heat pump outdoor temperature sensor error | Partly | Yes |
| H06.59 | HP suction temp Heat pump compressor suction temperature sensor error | Partly | Yes |
| H06.60 | HP inverter voltage The inverter voltage of the heat pump is too low | Partly | Yes |
| H06.61 | HP supply voltage The heat pump power supply voltage is out of range | Partly | Yes |
| H06.62 | HP discharge temp Heat pump compressor discharge temperature sensor error | Partly | Yes |
| H06.63 | HP EEPROM error Heat pump Inverter module EEPROM error | Partly | Yes |
| H06.64 | HP inverter com Communication error between the outdoor main control unit and the inverter module of the heat pump | Partly | Yes |
| H06.65 | HP high temp cooling HP refrigerant outlet temperature is too high in cooling mode | Partly | Yes |
| H06.66 | HP gas temp Heat pump gas temperature sensor error | Partly | Yes |
| H06.67 | ODU return high flow The heat pump return temperature is higher than the flow temperature in the outdoor unit | Partly | Yes |
| H06.68 | ODU air temp sensor Refrigerant outlet temperature sensor error in air side of heat exchanger of the outdoor unit | Partly | Yes |
| H06.69 | 3 phase sequence Invalid phase sequence in the 3 phase heat pump power supply | Partly | Yes |
| H06.75 | ODU flow error Water flow error active in the outdoor unit module | Partly | Yes |
| H06.76 | ODU return temp err Return temperature sensor is on error in the outdoor unit | Partly | Yes |
| H06.77 | ODU EEPROM error EEPROM error in hydronic system main control board in the outdoor unit | Partly | Yes |
| H06.78 | ODU internal com Err Communication error between refrigerant system and hydronic system main control boards | Partly | Yes |
| H06.79 | ODU flow temp err Flow temperature sensor is on error in the outdoor unit | Partly | Yes |
| H06.80 | HE frost protection ODU water side heat exchanger anti-freeze protection | Partly | Yes |
| H06.81 | Evaporator error Evaporator error in the outdoor unit | Partly | Yes |
| H06.99 | Compressor alarm Alarm related to the compressor raised by the inverter | Partly | Yes |
| H7 | Main circuit voltage failure | Not stated | Yes |
| H8 | Pressure sensor failure | Yes | Yes |
| H9 | System outlet water temperature sensor T1B failure | Not stated | Yes |
| H10.00 | T Flow Zone A Open Flow temperature sensor Zone A Open | Partly | Yes |
| H10.01 | T Flow Zone A Closed Flow temperature sensor Zone A Closed | Partly | Yes |
| H10.02 | T Dhw Zone A Open Domestic Hot Water temperature sensor Zone A Open | Partly | Yes |
| H10.03 | T Dhw Zone A Closed Domestic Hot Water temperature sensor Zone A Closed | Partly | Yes |
| H10.04 | TSwimmPoolZoneA Open Swimming Pool Temperature Sensor Zone A Open | Partly | Yes |
| H10.05 | TSwimmPoolZoneAClose Swimming Pool Temperature Sensor Zone A Closed | Partly | Yes |
| H10.09 | T Flow Zone B Open Flow temperature sensor Zone B Open | Partly | Yes |
| H10.10 | T Flow Zone B Closed Flow temperature sensor Zone B Closed | Partly | Yes |
| H10.11 | T Dhw Zone B Open Domestic Hot Water Temperature Sensor Zone B Open | Partly | Yes |
| H10.12 | T Dhw Zone B Closed Domestic Hot Water temperature sensor Zone B Closed | Partly | Yes |
| H10.13 | TSwimmPoolZoneB Open Swimming Pool Temperature Sensor Zone B Open | Partly | Yes |
| H10.14 | TSwimmPoolZoneBClose Swimming Pool Temperature Sensor Zone B Closed | Partly | Yes |
| H10.18 | T Flow Zone C Open Flow temperature sensor Zone C Open | Partly | Yes |
| H10.19 | T Flow Zone C Closed Flow temperature sensor Zone C Closed | Partly | Yes |
| H10.20 | T Dhw Zone C Open Domestic Hot Water Temperature Sensor Zone C Open | Partly | Yes |
| H10.21 | T Dhw Zone C Closed | Partly | Yes |
| H10.22 | TSwimmPoolZoneC Open Swimming Pool Temperature Sensor Zone C Open | Partly | Yes |
| H10.23 | TSwimmPoolZoneCClose Swimming Pool Temperature Sensor Zone C Closed | Partly | Yes |
| H10.27 | T Flow Zone DHW open Flow temperature sensor Zone DHW open | Partly | Yes |
| H10.28 | Sens. ZoneDHW closed Flow temperature sensor Zone DHW closed | Partly | Yes |
| H10.29 | Sensor Zone DHW open Temperature sensor Zone DHW open | Partly | Yes |
| H10.30 | T Zone DHW closed Domestic Hot Water temperature sensor Zone DHW closed | Partly | Yes |
| H10.36 | Sensor Zone AUX open Flow temperature sensor Zone AUX open | Partly | Yes |
| H10.37 | Sens. ZoneAUX closed Flow temperature sensor ZoneAUX closed | Partly | Yes |
| H10.38 | T Dhw Zone AUX open Domestic Hot Water temperature sensor Zone AUX open | Partly | Yes |
| H10.39 | Sens. ZoneAUX Closed Domestic Hot Water temperature sensor Zone AUX closed | Partly | Yes |
| HA | Plate heat exchanger water outlet temperature sensor (TW_out) error | Not stated | Yes |
| Hb | Three times 'PP' protection and Tw_out < 7°C | Yes | Yes |
| Hd | Communication fault between hydraulic module parallel (cascade master/slave) | Not stated | Yes |
| HE | Condenser refrigerant outlet temperature too high in heating mode for more than 10 minutes | Yes | Yes |
| HF | Main control board PCB B EEprom failure | Not stated | Yes |
| HH | H6 displayed 10 times in 2 hours | Yes | Yes |
| HL | PFC module fault | Yes | Yes |
| HP | Low pressure protection (Pe<0.6) occurred 3 times in an hour | Yes | Yes |
| J1E | Fan drive: hardware overcurrent protection | Not stated | Yes |
| J2E | Fan drive: overheating protection | Not stated | Yes |
| J3E | Fan drive: bus voltage too low error | Not stated | Yes |
| J5E | Fan motor failed to start | Not stated | Yes |
| J6E | Fan drive: phase loss protection | Not stated | Yes |
| J11 | Fan drive: phase current instantaneous overcurrent protection | Not stated | Yes |
| J12 | Fan drive: phase current continuous 30 s overcurrent protection | Not stated | Yes |
| J31 | Fan drive: bus voltage too high error | Not stated | Yes |
| J32 | Fan drive: bus voltage excessively high error | Not stated | Yes |
| J43 | Fan drive: abnormal phase current sampling bias | Not stated | Yes |
| J45 | Fan motor code mismatch error | Not stated | Yes |
| J46 | Fan drive: IPM protection (FO) | Not stated | Yes |
| J52 | Fan motor stalling protection | Not stated | Yes |
| J61 | Fan terminal short circuit protection | Not stated | Yes |
| J65 | Fan drive: IPM short circuit protection | Not stated | Yes |
| L0 | Module protection (P6 group) | Yes | Yes |
| L1 | Display reads L1 with audible alarm | Yes | Yes |
| L1E | Compressor drive: hardware overcurrent protection | Not stated | Yes |
| L2 | DC generatrix high voltage protection (P6 group) | Yes | Yes |
| L2E | Compressor drive: overheating protection | Not stated | Yes |
| L3E | Compressor drive: bus voltage too low error | Not stated | Yes |
| L4 | MCE malfunction (P6 group) | Yes | Yes |
| L5 | Zero speed protection (P6 group) | Yes | Yes |
| L5E | Compressor drive: motor failed to start | Not stated | Yes |
| L6E | Compressor drive: phase loss protection | Not stated | Yes |
| L7 | Phase sequence fault (P6/L-group) | Not stated | Yes |
| L8 | Speed difference >15Hz protection between the front and the back clock (P6 group) | Yes | Yes |
| L9 | Speed difference >15Hz protection between the real and the setting speed (P6 group) | Yes | Yes |
| L11 | Compressor drive: phase current instantaneous overcurrent protection | Not stated | Yes |
| L12 | Compressor drive: phase current continuous 30 s overcurrent protection | Not stated | Yes |
| L31 | Compressor drive: bus voltage too high error | Not stated | Yes |
| L32 | Compressor drive: bus voltage excessively high error | Not stated | Yes |
| L34 | Phase loss error on the three-phase power supply | Not stated | Yes |
| L43 | Compressor drive: abnormal phase current sampling bias | Not stated | Yes |
| L45 | Compressor drive: motor code mismatch error (printed 'Fan motor code mismatch error' in the L-series) | Not stated | Yes |
| L46 | Compressor drive: IPM protection (FO) | Not stated | Yes |
| L47 | Compressor drive: module type mismatch | Not stated | Yes |
| L52 | Compressor drive: motor stalling protection | Not stated | Yes |
| L61 | Compressor terminal short circuit protection | Not stated | Yes |
| L65 | Compressor drive: IPM short circuit protection | Not stated | Yes |
| LB7 | PED error | Not stated | Yes |
| LBE | Action of high pressure switch | Not stated | Yes |
| LC1 | Instantaneous overcurrent of PFC software protection | Not stated | Yes |
| LC2 | PFC software continuous 30 s overcurrent protection | Not stated | Yes |
| LC3 | PFC low voltage protection | Not stated | Yes |
| LC4 | PFC power factor is less than 0.8 | Not stated | Yes |
| LC5 | PFC valid value overcurrent protection | Not stated | Yes |
| LC6 | PFC1 channel hardware overcurrent protection | Not stated | Yes |
| LC7 | PFC2 channel hardware overcurrent protection | Not stated | Yes |
| LC8 | PFC3 channel hardware overcurrent protection | Not stated | Yes |
| LC9 | Overheating protection of PFC module | Not stated | Yes |
| LCA | PFC module CBC overcurrent error protection | Not stated | Yes |
| LCB | Overvoltage of PFC bus or PFC half bus | Not stated | Yes |
| LCC | Short circuit of PFC IGBT | Not stated | Yes |
| LCD | Abnormal PFC sampling bias | Not stated | Yes |
| LCE | PFC hardware overcurrent protection | Not stated | Yes |
| P0 | Low pressure protection | Yes | Yes |
| P1 | High pressure protection | Yes | Yes |
| P3 | Compressor overcurrent protection | Yes | Yes |
| P4 | High discharge temperature protection | Yes | Yes |
| P5 | High temperature difference protection between water inlet and outlet of the plate heat exchanger | Not stated | Yes |
| P6 | Module protection | Yes | Yes |
| P9 | DC fan motor protect | Not stated | Yes |
| P21 | L-SEN low pressure sensor error | Not stated | Yes |
| P27 | H-SEN and L-SEN connected in reverse (detected when the compressor is off) | Not stated | Yes |
| Pb | Anti-freeze mode protection | No | Yes |
| Pd | High temperature protection of refrigerant outlet temp of condenser | Yes | Yes |
| PE | Water pressure sensor failure | Not stated | Yes |
| PF | Water flow sensor failure | Not stated | Yes |
| PP | Water inlet temperature higher than water outlet in heating mode | Not stated | Yes |
| t1 | Display reads t1 with audible alarm | Yes | Yes |