Diagnostic Codes – Overview
| Code | Parameter | Values or Explanations | Factory Setting | User’s Custom Setting |
|---|---|---|---|---|
| D.000 | Partial heating power | Set partial heating power in kW auto: the product automatically adjusts the maximum partial heating power to the current system demand | auto | |
| D.001 | Internal pump run-on time after heating request | 2 … 60 min | 5 min | |
| D.002 | Maximum burner lock time for heating mode at a supply temperature of 20°C | 2 … 60 min | 20 min | |
| D.003 | Hot water temperature | Not connected | ||
| D.004 | Measured temperature value of the hot water storage tank in °C | If a hot water storage sensor is connected | Cannot be set | |
| D.005 | Set temperature value for heating water on the supply (or return set value) in °C | Current set value, set value of the parameter set for D.071, limited by the eBUS controller if connected | Cannot be set | |
| D.007 | Set temperature value of the hot water storage tank in °C | (15°C = freeze protection, from 40°C to D.020 (max. 70°C)) | Cannot be set | |
| D.009 | Heating water temperature on the supply, set value from external eBUS controller | ℃ | ||
| D.010 | State of the internal heating circuit pump | 0 = off. 1 = on. | Cannot be set | |
| D.011 | State of the additional external heating circuit pump | 0 = off. 1 -100 = on. | Cannot be set | |
| D.012 | State of the storage tank charging pump | 0 = off. 1 -100 = on. | Cannot be set | |
| D.013 | State of the circulating pump | 0 = off. 1 -100 = on. | Cannot be set | |
| D.014 | Setting of the internal heating circuit pump controlled by the number of rotations | 0 = auto (pump modulates based on regulation, with constant pressure) from 1 to 5 = fixed pump setting – 1 = 53% – 2 = 60% – 3 = 70% – 4 = 85% – 5 = 100% |
0 | |
| D.015 | Current number of rotations of the internal heating circuit pump in % | Cannot be set | ||
| D.016 | Room thermostat 24 V DC open / closed | Heating mode off / on. | Cannot be set | |
| D.017 | Type of heating system regulation | 0 = supply water temperature regulation 1 = return water temperature regulation | 0 | |
| D.018 | Setting of the pump run type | 1 = comfort (pump working continuously) 3 = eco (pump in intermittent mode) | 3 | |
| D.020 | Max. set value of the storage tank temperature | 50 … 65 °C | 65 °C | |
| D.022 | Hot water demand | 0 = off. 1 = on. | Cannot be set | |
| D.023 | Heating request | 0 = off. 1 = on. | Cannot be set | |
| D.024 | State of the air pressure control sensor | 0 = open 1 = closed | Cannot be set | |
| D.025 | Preparation of hot water, unlocked by eBUS controller | 0 = no 1 = yes | ||
| D.026 | Control of optional grey relay X16 | 1 = circulation pump 2 = external pump 3 = charging pump 4 = flue damper 5 = external solenoid valve 6 = external fault message 7 = solar pump (inactive) 8 = remote control eBUS (inactive) 9 = pump for Legionella protection (inactive) 10 = solar valve (inactive) |
2 | |
| D.027 | Switching relay 1 for multifunction module equipment | 1 = circulation pump 2 = external pump 3 = charging pump (inactive) 4 = flue damper 5 = external solenoid valve 6 = external fault message 7 = solar pump (inactive) 8 = remote control eBUS (inactive) 9 = pump for Legionella protection (inactive) |
1 | |
| D.028 | Switching relay 2 for multifunction module equipment | 1 = circulation pump 2 = external pump 3 = charging pump (inactive) 4 = flue damper 5 = external solenoid valve 6 = external fault message 7 = solar pump (inactive) 8 = remote control eBUS (inactive) 9 = pump for Legionella protection (inactive) |
2 | |
| D.029 | Heating water flow (heating circuit or storage tank charging) | l/min | Cannot be set | |
| D.033 | Fan speed set value | rpm | Cannot be set | |
| D.034 | Actual fan speed value | rpm | Cannot be set | |
| D.035 | Position of the priority two-way valve | Not connected | Cannot be set | |
| D.040 | Supply temperature | Actual value in °C | Cannot be set | |
| D.041 | Return temperature | Actual value in °C | Cannot be set | |
| D.044 | Digital ionization value | 0 … 1,020 Good flame < 400 No flame > 800 |
Cannot be set | |
| D.047 | External temperature (with weather regulating controller) | Actual value in °C, if the external temperature sensor is connected to X41 | Cannot be set | |
| D.050 | Relative offset for minimum rotations | 0 … 3,000 rpm | 30 | |
| D.051 | Relative offset for maximum rotations | −990 … 0 rpm | -45 | |
| D.060 | Number of overheat limiter STB shutdowns | Number of shutdowns | Cannot be set | |
| D.061 | Number of automatic ignition shutdowns | Number of failed ignitions in the last attempt | Cannot be set | |
| D.064 | Average ignition time | s | Cannot be set | |
| D.065 | Maximum ignition time | s | Cannot be set | |
| D.067 | Remaining burner lock time | min | Cannot be set | |
| D.068 | Failed ignitions on the first attempt | Number of failed ignitions | Cannot be set | |
| D.069 | Failed ignitions on the second attempt | Number of failed ignitions | Cannot be set | |
| D.071 | Maximum set supply temperature for heating | 30 … 80 ℃ | 75 ℃ | |
| D.072 | Heating circuit pump run time after additional storage tank heating | 0 … 600 s | 120 s | |
| D.074 | Legionella protection function | Thermal disinfection is performed every 24 hours 0 = inactive 1 = active |
0 | |
| D.075 | Maximum storage tank charging time | 20 … 90 min | 45 min | |
| D.076 | Product individual number | Device variant screen (DSN) | Cannot be set | |
| D.077 | Storage tank charging power limit | Set charging power of the storage tank in kW | Maximum power | |
| D.078 | Storage tank charging temperature limit (supply temperature set value during charging) in °C | 55 … 85 ℃ | 80 ℃ | |
| D.080 | Burner operating hours in heating mode | h | Cannot be set | |
| D.081 | Burner operating hours for water heating | h | Cannot be set | |
| D.082 | Number of burner starts in heating mode | Number of burner starts (x 100) | Cannot be set | |
| D.083 | Number of burner starts in hot water mode | Number of burner starts (x 100) | Cannot be set | |
| D.084 | Maintenance indicator: hours to next maintenance | 0 … 3,000 h “-” to deactivate function |
“-” | |
| D.085 | Minimal product power | kW | ||
| D.090 | eBUS controller status | 1 = detected 2 = not detected | Cannot be set | |
| D.091 | DCF status with external temperature sensor connected | 0 = no reception 1 = reception 2 = synchronization 3 = important |
Cannot be set | |
| D.093 | Setting for device variant (DSN) | Setting range: 170 to 199 The three-digit DSN code is provided on the product’s nameplate. |
||
| D.094 | Delete fault list | Delete fault list 0 = no 1 = yes |
||
| D.095 | Software version – eBUS components | Main electronic board (BMU) Electronic board of the control element (AI) |
Cannot be set | |
| D.096 | Factory reset | Reset all set parameters to factory settings 0 = no 1 = yes |
||
| D.122 | Set value of available pressure in the heating circuit | 100 … 400 mbar | 200 mbar | |
| D.123 | Duration of the last storage tank charging | min | ||
| D.124 | ECO mode for hot water storage | Not connected | ||
| D.125 | Hot water temperature at the storage tank outlet | Not connected | ||
| D.126 | Delay of additional heating due to sunlight | Not connected | ||
| D.148 | Set value of available pressure in the storage tank charging circuit | 100 … 400 mbar | 200 mbar | |
| D.149 | Detailed information on the circulation error F.75 | If error F.75 occurs, read the following explanation for each diagnosis code value to analyze the problem. 0 = no fault 1 = pump blocked 2 = electrical pump fault 3 = pump idling 5 = pressure sensor malfunction 6 = no feedback signal from the pump 7 = incorrect pump detected 8 = insufficient flow at the end of the venting program |
State Codes – Overview
| State Code | Meaning |
|---|---|
| Heating Mode | |
| S.1 | Heating mode fan startup |
| S.2 | Heating mode pump startup |
| S.3 | Heating mode ignition |
| S.4 | Heating mode burner turned on |
| S.5 | Heating mode – pump / fan run down |
| S.6 | Heating mode fan reduction |
| S.7 | Heating mode pump run down |
| S.8 | Heating mode burner lockout time |
| Hot Water Storage Mode | |
| S.20 | Hot water demand |
| S.21 | Hot water fan startup |
| S.22 | Hot water preparation pump running |
| S.23 | Hot water mode ignition |
| S.24 | Hot water mode burner turned on |
| S.25 | Hot water usage pump / fan run down |
| S.26 | Hot water fan run down |
| S.27 | Hot water pump run down |
| S.28 | Hot water time burner lockout |
| Special Cases | |
| S.30 | Room thermostat (RT) blocks heating mode |
| S.31 | Active summer mode of the system or no heat demand signal from the eBUS controller |
| S.32 | Waiting time fan speed deviation |
| S.33 | Calibration of air pressure switch |
| S.34 | Active frost protection function for the system |
| S.36 | Continuous controller setting 7-8-9 or eBUS controller setting < 20 °C and blocking heating mode |
| S.39 | Maximum underfloor heating thermostat triggered |
| S.41 | Water pressure too high |
| S.42 | Flue damper feedback signal (only with accessories) blocks burner operation or faulty condensate pump, heat demand is blocked |
| S.53 | Modulation blocked by device operation lockout due to water shortage (difference between supply and return too high) |
| S.54 | Product in standby mode due to device operation lockout due to water shortage (temperature gradient) |
| S.85 | Service message “Insufficient water flow, product in standby mode for 10 minutes” |
| S.96 | Return sensor test in progress, heat demand signals are blocked. |
| S.97 | Water pressure sensor test in progress, heat demand signals are blocked. |
| S.98 | Supply/return sensor test in progress, heat demand signals are blocked. |
| S.108 | Bleeding process in progress |
Error Messages – Overview
| Error Message | Possible Cause | Action |
|---|---|---|
| F.00 Power Supply Temperature Sensor Break | NTC sensor plug not inserted/loose | Check the NTC sensor plug and the connector. |
| NTC sensor damaged | Replace the NTC sensor. | |
| Improperly inserted/loose plug connection | Check the plug connection and the connector. | |
| Wiring harness interruption | Check the wiring harness. | |
| F.01 Return Temperature Sensor Break | NTC sensor plug not inserted/loose | Check the NTC sensor plug and the connector. |
| NTC sensor damaged | Replace the NTC sensor. | |
| Improperly inserted/loose plug connection | Check the plug connection and the connector. | |
| Wiring harness interruption | Check the wiring harness. | |
| F.03 Storage Temperature Sensor Break | NTC sensor damaged | Replace the NTC sensor. |
| NTC sensor plug not inserted/loose | Check the NTC sensor plug and the connector. | |
| Damage to the connection to the storage electronics | Check the connection to the storage electronics. | |
| F.10 Power Supply Temperature Sensor Short Circuit | NTC sensor damaged | Replace the NTC sensor. |
| Short circuit in the wiring harness | Check the wiring harness. | |
| F.11 Return Temperature Sensor Short Circuit | NTC sensor damaged | Replace the NTC sensor. |
| Short circuit in the wiring harness | Check the wiring harness. | |
| F.13 Storage Temperature Sensor Short Circuit | NTC sensor damaged | Replace the NTC sensor. |
| Short circuit in the wiring harness | Check the wiring harness. | |
| F.20 Emergency Shutdown: Overheating Limit STB | Power supply NTC damaged | Check the power supply NTC. |
| Return NTC damaged | Check the return NTC. | |
| Incorrect ground connection | Check the ground connection. | |
| Discharge through ignition cable, ignition plug, or ignition electrode | Check the ignition cable, ignition plug, and ignition electrode. | |
| F.22 Emergency Shutdown: Water Shortage | Too little/no water in the product | Fill the heating system. |
| Wiring harness interruption | Check the wiring harness. | |
| F.23 Safety Shutdown: Too Large Temperature Difference | Pump blocked | Check the pump for functionality. |
| Pump running with low power | Check the pump for functionality. | |
| Reversed power and return NTC connections | Check the power and return NTC connections. | |
| F.24 Safety Shutdown: Too Fast Temperature Rise | Pump blocked | Check the pump for functionality. |
| Pump running with low power | Check the pump for functionality. | |
| Check valve blocked | Check the check valve for functionality. | |
| Check valve incorrectly installed | Check the mounting position of the check valve. | |
| Low pressure in the system | Check the pressure in the system. | |
| F.25 Safety Shutdown: Excessive flue gas temperature | Safety temperature limiter plug not inserted/loose | Check the plug and the connector. |
| Wiring harness interruption | Check the wiring harness. | |
| F.27 Safety Shutdown: Incorrect flame detection | Gas solenoid valve leaking | Check the gas solenoid valve for proper functionality. |
| Moisture on the electronic board | Check the electronic board for proper functionality. | |
| Flame loss detector damaged | Replace the flame loss detector. | |
| F.28 Failed ignition | Gas shut-off valve closed | Open the gas shut-off valve. |
| Damaged gas equipment | Replace the gas equipment. | |
| Gas pressure sensor triggered | Check the gas pressure. | |
| Gas flow pressure too low | Check the gas pressure. | |
| Thermal shut-off valve triggered | Check the thermal shut-off valve. | |
| Loose/incorrectly inserted cable terminals | Check the cable terminals. | |
| Damaged ignition device | Replace the ignition device. | |
| Damaged electronic board | Replace the electronic board. | |
| Ionization current error | Check the ionization electrode. | |
| Improper grounding | Check the grounding of the product. | |
| Air in the gas line | Check the gas-to-air ratio. | |
| Damaged gas meter | Replace the gas meter. | |
| Gas supply is interrupted | Check the gas supply. | |
| Incorrect flue gas circulation | Check the air-flue gas system. | |
| Ignition failure | Check the ignition transformer for proper functionality. | |
| Diagnosis code D.085 incorrectly set | Check in the flue gas backflow installation if the diagnosis code D.085 is correctly adjusted. | |
| Incorrect product code | For air-flue systems with large lengths, check if the product code is correctly adjusted. | |
| Condensate drain siphon clogged | 1. Check if the condensate drain is properly connected. 2. If clogged, check if the internal insulation material of the heat exchanger is damaged. |
|
| F.29 Ignition and control error during operation – flame extinguished | Damaged gas equipment | Replace the gas equipment. |
| Damaged gas meter | Replace the gas meter. | |
| Gas pressure sensor triggered | Check the gas pressure. | |
| Air in the gas line | Check the gas-to-air ratio. | |
| Gas flow pressure too low | Check the gas pressure. | |
| Thermal shut-off valve triggered | Check the thermal shut-off valve. | |
| Loose/incorrectly inserted cable terminals | Check the cable terminals. | |
| Damaged ignition device | Replace the ignition device. | |
| Ionization current error | Check the ionization electrode. | |
| Improper grounding | Check the grounding of the product. | |
| Damaged electronic board | Replace the electronic board. | |
| F.32 Fan fault | Plug on fan not inserted/loose | Check the plug on the fan and the connector. |
| Improperly inserted/loose plug connection | Check the plug connection and the connector. | |
| Wiring harness interruption | Check the wiring harness. | |
| Fan blocked | Check the fan for functionality. | |
| Electronic system damage | Check the electronic board. | |
| F.33 Air pressure switch fault | Air-flue system blocked | Check the entire air-flue system. |
| Air pressure switch damaged | Replace the air pressure switch. | |
| Loose/incorrectly inserted cable terminals | Check the cable terminals. | |
| Fan fault | Check the fan for functionality. | |
| Damaged electronic board | Replace the electronic board. | |
| Too high backpressure in the air-flue system | 1. Ensure no danger of excessive backpressure. 2. If necessary, secure the product (wind shield, larger diameter cascading pipes…). |
|
| F.49 eBUS fault | eBUS overload | Check the eBUS connection for functionality. |
| Short circuit on eBUS connection | Check the eBUS connection for functionality. | |
| Opposite polarities on eBUS connection | Check the eBUS connection for functionality. | |
| F.61 Gas safety valve drive fault | Short circuit in wiring harness | Check the wiring harness. |
| Damaged gas equipment | Replace the gas equipment. | |
| Damaged electronic board | Replace the electronic board. | |
| F.62 Gas safety valve connection fault | Damaged electronic board | Replace the electronic board. |
| Connection to gas equipment interrupted/interfered | Check the connection to the gas equipment. | |
| F.63 EEPROM (programmable permanent memory) fault | Damaged electronic board | Replace the electronic board. |
| F.64 Electronic system / NTC fault | Power supply NTC short circuit | Check the power supply NTC for functionality. |
| Return NTC short circuit | Check the return NTC for functionality. | |
| Damaged electronic board | Replace the electronic board. | |
| F.65 Electronic temperature error | Overheated electronics | Check external heat sources affecting the electronics. |
| Damaged electronic board | Replace the electronic board and the ionization electrode. | |
| F.67 Flame validity error | Damaged electronic board | Replace the electronic board. |
| F.70 Incorrect device number (DSN) | Device number not set/incorrectly set | Set the correct device number. |
| Missing or incorrect nominal power coding resistor | Check the nominal power coding resistor. | |
| F.71 Power supply temperature sensor fault | Power NTC reports a constant value | Check the position of the power NTC. |
| Power NTC in wrong position | Check the position of the power NTC. | |
| Power NTC damaged | Replace the power NTC. | |
| F.72 Power supply and/or return temperature sensor fault | Power NTC damaged | Replace the power NTC. |
| Return NTC damaged | Replace the return NTC. | |
| F.73 Pressure sensor signal out of range (pressure too low) | Short circuit in wiring harness | Check the wiring harness. |
| Wiring harness interruption | Check the wiring harness. | |
| Water pressure sensor fault | Replace the water pressure sensor. | |
| F.74 Water pressure sensor signal out of range (pressure too high) | Short circuit in the wiring harness | Check the wiring harness. |
| Wiring harness interruption | Check the wiring harness. | |
| Water pressure sensor fault | Replace the water pressure sensor. | |
| F.75 Pump/water shortage error | Operational disturbances | Refer to diagnosis code D.149 for more information on operational disturbances. |
| D.149 = 1, alarm pump blocked | 1. Unblock the pump. 2. Replace the pump. |
|
| D.149 = 2, alarm electrical fault in pump | 1. Check the pump power supply. 2. Replace the pump. |
|
| D.149 = 3, alarm pump idling | 1. Check the hydraulic circuit pressure, ensure that air is in the circuit. 2. Replace the pump. |
|
| D.149 = 5, no peak pressure value detected | 1. Check the pressure in the system. 2. Bleed the heating system (air removal program). 3. Check the water pressure sensor. 4. Replace the water pressure sensor. |
|
| D.149 = 6, no pump feedback signal | 1. Check the pump wiring harness. 2. Check the main electronic board. 3. Check if the plugs are properly inserted. 4. Check the pump power supply – ≥ 195 V. 5. Replace the pump. 6. Replace the main electronic board. |
|
| D.149 = 7, invalid pump detected | 1. The detected pump does not match the product code, check the product code. 2. Use the pump with the correct article number. |
|
| D.149 = 8, insufficient flow at the end of the air removal program | 1. Check if the shut-off valves and thermostatic valves are open. 2. Check the filling pressure, bleed the circuit – ≥ 0.15 MPa (≥ 1.50 bar). |
|
| F.77 Accessory fault (flue damper, condensate pump …) | No or incorrect feedback signal from the flue damper | Check the correct operation of the flue damper. |
| Damaged flue damper | Replace the flue damper. | |
| No or incorrect feedback signal from the condensate pump | Check the condensate pump for functionality. | |
| F.83 Temperature sensor change error (supply and/or return temperature sensor) | Water shortage | Fill the heating system. |
| No contact with supply NTC | Check if the supply NTC properly touches the supply pipe. | |
| No contact with return NTC | Check if the return NTC properly touches the return pipe. | |
| F.84 Temperature difference error between supply and return temperature sensor | Supply NTC improperly installed | Check if the supply NTC is properly installed. |
| Return NTC improperly installed | Check if the return NTC is properly installed. | |
| F.85 Supply and return temperature sensors improperly installed (swapped) | Supply/return NTC installed on the same/wrong pipe | Check if the supply and return NTCs are installed on the correct pipes. |