| F.00 Interruption: Flow sensor |
Flow temperature sensor defective or not connected |
| F.01 Interruption: Return sensor |
Return temperature sensor defective or not connected |
| F.10 Short circuit: Flow sensor |
Flow temperature sensor defective or has short-circuited |
| F.11 Short circuit: Return sensor |
Return temperature sensor defective or has short-circuited |
| F.20 Safety switch-off: Temperature limiter |
Maximum temperature at the flow/return temperature sensor is too high when the safety cut out function is operating using the NTC |
| F.22 Safety switch-off: Low water pressure |
No/insufficient water in the product or the water pressure is too low |
| F.23 Safety switch-off: Temp. spread too large |
Temperature spread too great. Water circulation too low |
| F.24 Safety switch-off: Temp. incr. too fast |
Temperature increase too fast |
| F.25 Safety switch-off: Flue temp. too high |
Flue gas temperature too high |
| F.26 Fault: Fuel valve not working |
Gas valve assembly stepper motor defective or not connected |
| F.27 Safety switch-off: Flame simulation |
Monitoring electrode reports an incorrect flame |
| F.28 Start-up failure: Ignit. unsuccessful |
Failure during start-up or ignition unsuccessful. Gas pressure monitor or thermal cut-out has been triggered. |
| F.29 Operating failure: Ignit. unsuccessful |
Gas supply interrupted intermittently. Re-ignition failed. |
| F.32 Fault: Fan |
Fan defective or not connected |
| F.49 Fault: eBUS |
Undervoltage on the eBUS |
| F.61 Fault: Fuel valve actuation |
The gas valve assembly cannot be actuated |
| F.62 Fault: Fuel valve switch off delay |
Delayed switch-off sequence for the gas valve after the flame is extinguished |
| F.63 Fault: EPROM |
EEPROM faulty |
| F.64 Fault: Electronics/sensor |
Electronics, safety-relevant sensor or cable defective |
| F.65 Fault: Electronics temp. |
Electronics defective or too hot due to external influences |
| F.67 Fault: Electronics/flame |
Implausible flame signal |
| F.68 Fault: Flame signal un stable |
Flame monitor reports an un stable flame signal |
| F.70 Fault: Invalid Device Specific Number |
Incorrect/missing Device Specific Number or incorrect/missing coding resistor |
| F.71 Fault: Flow sensor |
Flow temperature sensor re turns implausible values |
| F.72 Fault: Flow/return sensor |
Temperature difference between flow and return temperature sensor is too great |
| F.73 Fault: Water press. sensor (signal too weak) |
Water pressure sensor reports that the water pressure is too low |
| F.74 Fault: Water press. sensor (signal too strong) |
Water pressure too high |
| F.75 Fault: Pump/ water shortage |
Insufficient pressure jump de tected when starting the pump |
| F.77 Fault: Flue non-ret. valve/condens. pump |
No flue non-return flap feed back; condensate pump over flow |
| F.78 Interrupt.: DHW outlet sensor on ext. contr. |
UK link box is connected without the domestic hot water temperature sensor being bridged |
| F.83 Fault: NTC temp. gradient |
Temperature difference between flow and return temperature sensor is too small |
| F.84 Fault: NTC temp. diff. implausible |
Temperature difference is im plausible |
| F.85 Fault: NTCs fitted incorrectly |
Flow/return temperature sensors returning incorrect/implausible values |
| Communication fault |
Communication fault between the display and the PCB in the electronics box |
