Ochsner · A niche brand in the UK. 145 codes across 2 product families, each taken from the manufacturer’s manuals. Ochsner technical support ↗
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145 codes
| Code | Meaning | Stops? | Homeowner check? |
|---|---|---|---|
| #1 | DHW temperature - troubleshooting: Check sensor position/replace sensor, check wiring | Not stated | Yes |
| #2 | DHW circulation pump return temperature - troubleshooting: Check sensor position/replace sensor, check wiring | Not stated | Yes |
| #4 | Charging shutdown - safety function limiting heat pump charging (manual section 22.1.1 p.48) | Not stated | Yes |
| #5 | Emergency mode, DHW - troubleshooting: Contact service partner | Not stated | Yes |
| #8 | Minimum system pressure, heat sink system - troubleshooting: Check system pressure in heat sink system, replace sensor, check wiring, check hydraulics | Not stated | Yes |
| #9 | System pressure, heat sink system - troubleshooting: Check system pressure in heat sink system, replace sensor, check wiring, check hydraulics | Not stated | Yes |
| #10 | Outdoor temperature - troubleshooting: Replace sensor, check wiring | Not stated | Yes |
| #11.1 | Maximum excess temperature, heating circuit 1 - troubleshooting: Check customer settings (heating curve, max. flow temperature), check 3-way switching module for heating/DHW, mixing valve | Not stated | Yes |
| #11.2 | Maximum excess temperature, heating circuit 2 - troubleshooting: Check customer settings (heating curve, max. flow temperature), check 3-way switching module for heating/DHW, mixing valve | Not stated | Yes |
| #11.3 | Maximum excess temperature, heating circuit 3 - troubleshooting: Check customer settings (heating curve, max. flow temperature), check 3-way switching module for heating/DHW, mixing valve | Not stated | Yes |
| #11.4 | Maximum excess temperature, heating circuit 4 - troubleshooting: Check customer settings (heating curve, max. flow temperature), check 3-way switching module for heating/DHW, mixing valve | Not stated | Yes |
| #12.1 | Dew point undershot, heating circuit 1 - troubleshooting: Customer settings (cooling curve), humidity sensor, | Not stated | Yes |
| #12.2 | Dew point undershot, heating circuit 2 - troubleshooting: Customer settings (cooling curve), humidity sensor, | Not stated | Yes |
| #12.3 | Dew point undershot, heating circuit 3 - troubleshooting: Customer settings (cooling curve), humidity sensor, | Not stated | Yes |
| #12.4 | Dew point undershot, heating circuit 4 - troubleshooting: Customer settings (cooling curve), humidity sensor, | Not stated | Yes |
| #14.1 | Flow temperature heating circuit 1 - troubleshooting: Replace sensor, check wiring | Not stated | Yes |
| #14.2 | Flow temperature heating circuit 2 - troubleshooting: Replace sensor, check wiring | Not stated | Yes |
| #14.3 | Flow temperature heating circuit 3 - troubleshooting: Replace sensor, check wiring | Not stated | Yes |
| #14.4 | Flow temperature heating circuit 4 - troubleshooting: Replace sensor, check wiring | Not stated | Yes |
| #15.1 | Timeout, screed drying program, heating circuit 1 - troubleshooting: Check settings, check heat pump output, shut off building zones if required | Not stated | Yes |
| #15.2 | Timeout, screed drying program, heating circuit 2 - troubleshooting: Check settings, check heat pump output, shut off building zones if required | Not stated | Yes |
| #15.3 | Timeout, screed drying program, heating circuit 3 - troubleshooting: Check settings, check heat pump output, shut off building zones if required | Not stated | Yes |
| #15.4 | Timeout, screed drying program, heating circuit 4 - troubleshooting: Check settings, check heat pump output, shut off building zones if required | Not stated | Yes |
| #16 | Emergency mode, heating circuit - troubleshooting: Contact service partner | Not stated | Yes |
| #20.1 | Heat pump return temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #20.2 | Temperature sensor, heat pump return not plausible - troubleshooting: Contact service partner | Not stated | Yes |
| #22.1 | Buffer tank temperature, bottom - troubleshooting: Replace sensor, check wiring | Not stated | Yes |
| #22.2 | Buffer tank 2 temperature, bottom - troubleshooting: Replace sensor, check wiring | Not stated | Yes |
| #24.1 | Buffer tank temperature, top - troubleshooting: Replace sensor, check wiring | Not stated | Yes |
| #24.2 | Buffer tank 2 temperature, top - troubleshooting: Replace sensor, check wiring | Not stated | Yes |
| #27 | Compressor oil temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #28 | Flow temperature auxiliary heater - troubleshooting: Contact service partner | Not stated | Yes |
| #29 | Heat pump flow temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #30 | Phase monitor - troubleshooting: Contact service partner | Not stated | Yes |
| #32 | Hot gas temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #35 | Low pressure sensor for outdoor unit - troubleshooting: Contact service partner | Not stated | Yes |
| #36.1 | Maximum high pressure (envelope) - troubleshooting: Contact service partner | Not stated | Yes |
| #36.2 | Minimum high pressure (envelope) - troubleshooting: Contact service partner | Not stated | Yes |
| #36.3 | High pressure - troubleshooting: Contact service partner | Not stated | Yes |
| #37.1 | Low pressure - troubleshooting: Contact service partner | Not stated | Yes |
| #37.2 | Maximum low pressure (envelope) - troubleshooting: Contact service partner | Not stated | Yes |
| #38 | Maximum hot gas temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #39 | Compressor motor protection - troubleshooting: Contact service partner | Not stated | Yes |
| #40 | Temperature upstream of expansion valve - troubleshooting: Contact service partner | Not stated | Yes |
| #41 | Temperature upstream of expansion valve 2 - troubleshooting: Contact service partner | Not stated | Yes |
| #42 | Minimum cooling/ defrosting operating temperature - troubleshooting: Insufficient heat distribution, circulation pump faulty, valve closed/air in system, check buffer charging pump and hydraulics, system temperatures too low | Not stated | Yes |
| #43 | High pressure sensor for outdoor unit - troubleshooting: Contact service partner | Not stated | Yes |
| #44 | Economiser expansion valve - troubleshooting: Contact service partner | Not stated | Yes |
| #46.1 | Compressor suction gas temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #46.2 | Evaporator suction gas temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #48 | Evaporator intake air temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #49 | Evaporator discharge air temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #50.1 | Expansion valve speed deviation (target-actual) - troubleshooting: Contact service partner | Not stated | Yes |
| #50.2 | Expansion valve out of service – not available for control - troubleshooting: Contact service partner | Not stated | Yes |
| #51 | Compressor speed - troubleshooting: Contact service partner | Not stated | Yes |
| #52 | Compressor speed deviation (target-actual) - troubleshooting: Contact service partner | Not stated | Yes |
| #53 | Compressor speed reduction (envelope) - troubleshooting: Contact service partner | Not stated | Yes |
| #54 | Transition timeout - troubleshooting: Contact service partner | Not stated | Yes |
| #55 | Transition timeout (refrigerant circuit stuck in transition) - troubleshooting: Contact service partner | Not stated | Yes |
| #58.1 | Fan and phases - troubleshooting: Contact service partner | Not stated | Yes |
| #58.2 | Fan and phases 2 - troubleshooting: Contact service partner | Not stated | Yes |
| #71.1 | Room temperature heating circuit 1 - troubleshooting: Contact service partner | Not stated | Yes |
| #71.2 | Room temperature heating circuit 2 - troubleshooting: Contact service partner | Not stated | Yes |
| #71.3 | Room temperature heating circuit 3 - troubleshooting: Contact service partner | Not stated | Yes |
| #71.4 | Room temperature heating circuit 4 - troubleshooting: Contact service partner | Not stated | Yes |
| #72.1 | Relative humidity heating circuit 1 - troubleshooting: Contact service partner | Not stated | Yes |
| #72.2 | Relative humidity heating circuit 2 - troubleshooting: Contact service partner | Not stated | Yes |
| #72.3 | Relative humidity heating circuit 3 - troubleshooting: Contact service partner | Not stated | Yes |
| #72.4 | Relative humidity heating circuit 4 - troubleshooting: Contact service partner | Not stated | Yes |
| #74 | Outside the envelope - troubleshooting: Contact service partner | Not stated | Yes |
| #75 | Economiser pressure - troubleshooting: Contact service partner | Not stated | Yes |
| #76 | Economiser temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #77 | Refrigerant temperature, condenser outlet - troubleshooting: Contact service partner | Not stated | Yes |
| #78 | Minimum heat recovery temperature - troubleshooting: Contact service partner | Not stated | Yes |
| #79 | Matrix fault (HWIO) - troubleshooting: Contact service partner | Not stated | Yes |
| #81 | Auxiliary heater stage 1 – not OK - troubleshooting: Check circuit breaker, check flow temperature sensor | Not stated | Yes |
| #82 | Auxiliary heater stage 2 – not OK - troubleshooting: Check circuit breaker, check flow temperature sensor | Not stated | Yes |
| #90 | Minimum superheating, expansion valve - troubleshooting: Contact service partner | Not stated | Yes |
| #90.1 | Minimum superheating, expansion valve 2 - troubleshooting: Contact service partner | Not stated | Yes |
| #90.2 | Minimum superheating, economiser - troubleshooting: Contact service partner | Not stated | Yes |
| #90.3 | Minimum superheating, heat recovery - troubleshooting: Contact service partner | Not stated | Yes |
| #90.4 | Minimum hot gas superheating undershot - troubleshooting: Contact service partner | Not stated | Yes |
| #90.5 | Minimum suction gas superheating undershot - troubleshooting: Contact service partner | Not stated | Yes |
| #91 | Minimum flow rate, heat sink system - troubleshooting: Water pressure too low, circulation pump faulty, valve closed/air in system, check hydraulics, check selected pump speeds, filter (strainer) clogged | Not stated | Yes |
| #91.1 | Minimum flow rate, heat recovery - troubleshooting: Contact service partner | Not stated | Yes |
| #91.2 | Heat sink system flow rate - troubleshooting: Contact service partner | Not stated | Yes |
| #100.1 | Communication, heat pump 1 - troubleshooting: Contact service partner | Not stated | Yes |
| #100.2 | Communication, heat pump 2 - troubleshooting: Contact service partner | Not stated | Yes |
| #100.3 | Communication, heat pump 3 - troubleshooting: Contact service partner | Not stated | Yes |
| #100.4 | Communication, heat pump 4 - troubleshooting: Contact service partner | Not stated | Yes |
| #101 | Maximum pressure ratio (envelope) - troubleshooting: Contact service partner | Not stated | Yes |
| #102 | Minimum pressure ratio (envelope) - troubleshooting: Contact service partner | Not stated | Yes |
| #104.1 | Outdoor unit 1 - troubleshooting: Contact service partner | Not stated | Yes |
| #104.2 | Outdoor unit 2 - troubleshooting: Contact service partner | Not stated | Yes |
| #110.2 | Pool - troubleshooting: Contact service partner | Not stated | Yes |
| #111 | External heat generator - troubleshooting: Contact service partner | Not stated | Yes |
| #112 | Refrigerant detected - troubleshooting: Contact service partner | Yes | Yes |
| #113 | Safety box - troubleshooting: Contact service partner | Not stated | Yes |
| Er01 | DHW sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er10 | Outdoor temperature sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er14 | Mixer sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er20 | TWR sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er22 | TPM or TWR shutdown sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er23 | TPV sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er24 | Buffer sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er29 | TWV sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er30 | Phase monitor. Cause/remedy per manual: Check power supply | Partly | Yes |
| Er32 | THG sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er33 | High pressure sensor faulty. Cause/remedy per manual: Check sensor | Partly | Yes |
| Er34 | Low pressure sensor faulty. Cause/remedy per manual: Check sensor | Partly | Yes |
| Er36 | High pressure. Cause/remedy per manual: Insufficient heat distribution, circulation pump faulty, valve closed/air in system Check hydraulics | Partly | Yes |
| Er37 | Low pressure. Cause/remedy per manual: Insufficient heat source energy, insufficient refrigerant, expansion valve Check refrigerant circuit Contact OCHSNER Customer Service. | Partly | Yes |
| Er38 | Hot gas. Cause/remedy per manual: Expansion valve, insufficient refrigerant, target value too high Check refrigerant circuit Contact OCHSNER Customer Service. | Partly | Yes |
| Er39 | Compressor motor protection. Cause/remedy per manual: Motor protection relay, phase fault/overload, source temperature too high Check compressor in refrigerant circuit Contact OCHSNER Customer Service. | Partly | Yes |
| Er42 | Heat sink frost protection. Cause/remedy per manual: Insufficient heat distribution, circulation pump faulty, valve closed/air in system Check buffer charging pump or hydraulics | Partly | Yes |
| Er46 | TSG sensor faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er47 | Defrost fault. Cause/remedy per manual: Insufficient defrosting energy, evaporator/sensor Check refrigerant circuit Contact OCHSNER Customer Service. | Partly | Yes |
| Er48 | TQE sensor/evaporator 1 faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er49 | TQA sensor/evaporator 2 faulty. Cause/remedy per manual: Replace sensor | Partly | Yes |
| Er50 | Expansion valve. Cause/remedy per manual: Check function of EEV and contact OCHSNER Customer Service. | Partly | Yes |
| Er56 | Heat source flow rate. Cause/remedy per manual: Insufficient heat source energy, heat source pump/ filter Flow rate in heat source too low | Partly | Yes |
| Er57 | Heat source frost protection. Cause/remedy per manual: Insufficient heat source energy, source temperature too low: Check heat source, check heat source pump, clean water filter, submersible pump faulty | Partly | Yes |
| Er58 | Heat source motor protection. Cause/remedy per manual: Check motor protection, check wiring to motor, motor protection relay, phase fault/overload, thermal contact | Partly | Yes |
| Er59 | TWV + TWR sensor break. Cause/remedy per manual: Check sensor | Partly | Yes |
| Er60 | TQA + TQE sensor break. Cause/remedy per manual: Check sensor | Partly | Yes |
| Er71 | Bus fault, remote controller. Cause/remedy per manual: Check eBus wiring | Partly | Yes |
| Er80 | Heat generator 1 address. Cause/remedy per manual: Check address | Partly | Yes |
| Er81 | Heat generator 2 address. Cause/remedy per manual: Check address | Partly | Yes |
| Er82 | Heat generator 3 address. Cause/remedy per manual: Check address | Partly | Yes |
| Er83 | Heat generator 4 address. Cause/remedy per manual: Check address | Partly | Yes |
| Er84 | Heat generator 5 address. Cause/remedy per manual: Check address | Partly | Yes |
| Er85 | Heat generator 6 address. Cause/remedy per manual: Check address | Partly | Yes |
| Er86 | Heat generator 7 address. Cause/remedy per manual: Check address | Partly | Yes |
| Er87 | Heat generator 8 address. Cause/remedy per manual: Check address | Partly | Yes |
| Er90 | Superheating. Cause/remedy per manual: Check refrigerant circuit and contact OCHSNER Customer Service. | Partly | Yes |
| Er91 | Heat sink flow rate. Cause/remedy per manual: Insufficient water pressure, circulation pump faulty, valve closed/air in system, check hydraulics | Partly | Yes |
| Er98 | Electric immersion heater running as sole heat generator!. Cause/remedy per manual: Check operating program of heat pump | Partly | Yes |
| Er104 | Sum fault, heat pump. Cause/remedy per manual: Contact OCHSNER Customer Service. | Partly | Yes |
| Er200 | Condensation temperature too low. Cause/remedy per manual: Check refrigerant circuit and contact OCHSNER Customer Service. | Partly | Yes |
| Er201 | Insufficient condensation - check the refrigerant circuit (OCHSNER) (older OTE3 SW5x wording) | Partly | Yes |
| Er202 | Evaporation temp. too low. Cause/remedy per manual: Check refrigerant circuit and contact OCHSNER Customer Service. | Partly | Yes |
| Er203 | Evaporation temp. too high. Cause/remedy per manual: Check refrigerant circuit and contact OCHSNER Customer Service. | Partly | Yes |
| Er240 | OTE does not detect a Modbus PCB. Cause/remedy per manual: Contact OCHSNER Customer Service. | Partly | Yes |
| Er241 | Modbus communication error | Partly | Yes |
| Er242 | Communication malfunction CAN bus | Partly | Yes |