| Fault Code | Possible Cause | Meaning |
|---|---|---|
| F.00 | NTC Faults | This means that your Flow NTC cable is defective or broken and needs to be replaced |
| F.01 | The Flow NTC cable is defective or broken and needs to be replaced | |
| F.10 | - | |
| F.11 | ||
| F.13 | - | |
| F.20 | Over heating problem. Boiler needs to cool down | |
| F.22 | Low water in system / overheat | This means that there’s either no water in your system, you have a defective pump or the pump lead is defective |
| F.24 | Pump failure or pump blocked | Anything that affects the pump’s ability to circulate water will contribute to the F24 fault code. |
| F.28 | No ignition/Ignition problem. No gas! | |
| F.29 | Flame loss.( Fan, flue or gas problem ) | Flame or pilot light has gone out – check flue duct or gas supply. |
| F.60 | Electrical fault with internal components | Cable loom might have short circuited, gas valve assembly defective or electronic control system issue. |
| F.61 | Gas valve control defective | Gas valve control defective( usually comes down to a faulty PCB ) |
| F.62 | Defective gas valve closure mechanism | Boiler over heating problem and needs to cool down |
| F.63 | EEPROM (Electrically Erasable Programmable Read-Only Memory) error | Electronic faults with internal components. |
| F.64 | Electronic system or sensor fault | Flow or back flow NTC has short circuited, or an electronic fault |
| F.65 | Electronic system temperature too high | This can happen because of an external heat source or an electrical fault |
| F.67 | Electronic fault in the flame system | - |
| Fault Code | Possible Cause |
|---|---|
| F.1 | No gas; Insufficient gas; Incorrect gas valve adjustment; Electrode defect; |
| F.4 | No gas; Insufficient gas; Incorrect gas valve adjustment; Electrode defect; |
| F.5 | Overheat stat operated; Maximum temperature exceeded; |
| F.6 | Your flow NTC has developed a fault. |
| F.17 | Check electrical supply / polarity, Check fan. |
| F.24 | System fault; Possible external pump failure; |
| Fault Code | Possible Cause |
|---|---|
| F.00, .04, .05, .10, .14, .15 | NTC Faults. |
| F.21 | Flame failure fault. |
| F.22 | There is insufficient water in your system. |
| F.11 | A blockage in the appliance is preventing the system from flowing as it should. |
| F.12 | Appliance blocked, low system pressure. |
| F.13 | Water deficiency, appliance blocked. |
| Fault Code | Possible Cause |
|---|---|
| S.O | Heating issue, no heat demand |
| S.1 | Fan start-up error |
| S.2 | Pump flow error |
| S.3 | Heating mode error – ignition problem |
| S.4 | Heat mode – burner on error |
| S.6 | Heating mode – fan overrun error |
| S.7 | Heating mode – pump overrun error |
| S.8 | Heating remaining cut off for XX amount of time |
| S.31 | No heat demand summer operating mode |
| S.34 | Heating mode frost protection error |
| S.20 | Hot water requirement error |
| S.22 | Hot water handling pump flow error |
| S.24 | Hot water operation burner is on |
| S.85 | Service message quantity of circulation water |
| Fault Code | Possible Cause |
|---|---|
| F.00 / F.0 | Flow temperature sensor de- fective or not connected |
| F.01 / F.1 | Return temperature sensor defective or not connected |
| F.10 | Flow NTC short circuit |
| F.11 | Return NTC short circuit |
| F.20 | Safety switch off temperature limiter |
| F.22 | Safety switch off low water pressure |
| F.23 | Temperature spread too great. Water circulation too low |
| F.24 | Temperature increase too fast |
| F.25 | Flue gas temperature too high |
| F.26 | Error with gas valve – possible no function |
| F.27 | Monitoring electrode reports an incorrect flame |
| F.28 | Failure during start up – ignition unsuccessful to start |
| F.29 | Failure during operation – re-ignition unsuccessful |
| F.32 | Fan defective or not connected |
| F.49 | eBUS error – possible short circuit |
| F.61 | The gas valve assembly cannot be actuated |
| F.62 | Error with gas valve – switch off delay |
| F.63 | EEPROM error |
| F.64 | Electronics, safety-relevant sensor or cable defective |
| F.65 | Electronic temperature error could be overheating due to external influences |
| F.67 | Electronics flame signal error |
| F.68 | Unstable flame signal error air in gas |
| F.70 | Invalid device specific number (DSN) |
| F.71 | Flow NTC error – flow temperature sensor signal constant value |
| F.72 | Flow return NTC error – temperature difference too great |
| F.73 | Water pressure sensor reports that the water pressure is too low |
| F.74 | Water pressure too high |
| F.75 | nsufficient pressure jump de tected when starting the pump |
| F.76 | Overheating protection on – primary heat exchanger has responded |
| F.77 | No flue non-return flap feed back; condensate pump over flow |
| F.78 | Interruption to DHW outlet sensor at external controller |
| Interruption to DHW outlet sensor at external controller | Temperature difference between flow and return temperature sensor is too small |
| F.84 | Error with flow/return temperature sensor temperature changing error |
| F.85 | Flow/return temperature sensors returning incorrect/implausible values |
| CONNECTION | Communication fault between the display and the PCB in the electronics box |
| Fault Code | Possible Cause |
|---|---|
| S.00 | Heating mode error – no heat demand |
| S.01 | Heating mode fan start-up |
| S.02 | Heating mode: Pump pre-run |
| S.03 | Heating mode – ignition sequence error |
| S.04 | Heating mode – burner ignited |
| S.06 | Heating mode – fan overrun error |
| S.07 | Heating mode – pump overrun error |
| S.08 | Heating remaining cut off time xx minutes |
| S.10 | Hot water demand via impeller sensor |
| S.11 | DHW mode fan start up error |
| S13 | DHW mode ignition error |
| S.14 | Hot water demand via fan sensor error |
| S.15 | DHW mode pump and fan overrun |
| S.16 | DHW mode – fan overrun error |
| S.17 | DHW mode – pump overrun error |
| S.20 | DHW mode – burner on error |
| S.21 | DHW mode – fan start up error |
| S.22 | DHW demand – error pump running |
| S.22 | DHW demand – error pump running |
| S.23 | DHW ignition error |
| S.24 | DHW mode – burner error |
| S.25 | DHW mode – pump or fan overrun error |
| S.26 | DHW mode – fan overrun |
| S.27 | DHW mode – pump overrun |
| S.28 | Hot water burner anti-cycling time |
| S.30 | Room thermostat is blocking heating mode |
| S.31 | No heat demand: Summer mode |
| S.32 | Waiting period because of fan speed deviation |
| S.34 | Heating mode frost protection error |
| S.39 | Burner off contact has been triggered this could be because of contact thermostat or condensate pump |
| S.40 | Comfort safety mode active |
| S.41 | Water pressure > 2.8 bar |
| S.42 | Flue non return flap return signal blocks burner operation |
| S.46 | Comfort protection mode, flame loss at minimum load |
| S.53 | Boiler is in waiting period of modulation f block function due to water shortage |
| S.54 | Boiler is in waiting period of operation, blocking function as a result |
| S.57 | Waiting period comfort safety mode |
| S.58 | Modulation limitation due to noise / wind error |
| S.61 | Gas family check unsuccessful |
