Saunier Duval IsoFast H-Condens faults
Identify the code and check the version of your boiler.
Check the model and reference of the device.
Guide to IsoFast H-Condens MA 36-CF/1 (N-INT)for the appliance references 0010025226 and 0010034218 declared on page 7 of manual 0020298498_00, dated 22/04/2021. The catalog sells the presentation MA 36-CF/1-CfI (N-INT). Confirm the accessible identification before using the table; it does not correspond to the IsoFast MA35-CS.
The edition that explicitly names N-INT is used. The subsequent documentation 0020298498_03 uses N-ES for those references; if the documentation that accompanies your unit differs, the one for that unit must prevail.
Find the message on the screen.
- F.022
Insufficient water or pressure.
- F.028
The ignition does not confirm flame.
- F.075
Insufficient pressure variation when starting the pump.
What can you check without opening the boiler?
Note the complete code, the indicated pressure, and whether it occurs when requesting heating or hot water. Provide a photograph of the display and the accessible identification. Avoid repeated resets if the fault returns; use only the operations from the user manual of your unit.
Do not open the casing or manipulate gas, electrical connections, combustion, or flue gas. If you smell gas, avoid flames and switches, leave the area, and notify the distributor's emergency service from a safe location; in case of immediate danger, call 112.
Saunier Duval IsoFast H-Condens components Manufacturer's diagram
N-INT edition codes
The 71 notices below summarize the meaning of the fault code, without reproducing the repair operations. The manufacturer indicates that some entries depend on the configuration. The table does not measure the frequency of faults nor does it identify a spare part on its own.
| Code | What does it indicate? |
|---|---|
| F.000 | The temperature signal is missing in the heating supply. |
| F.001 | The return temperature signal is missing. |
| F.002 | The temperature signal is lost in the sanitary connection. |
| F.003 | The temperature reading of the accumulator is lost. |
| F.010 | Short circuit in the supply temperature measurement. |
| F.011 | Short circuit in the return temperature measurement. |
| F.012 | Short circuit in the domestic hot water sensor. |
| F.013 | Short circuit in the thermal sensor of the accumulator. |
| F.020 | The thermal safety device stops the gas flow when the permissible temperature is exceeded. |
| F.022 | Lack of water or insufficient water pressure. |
| F.023 | Excessive difference between the supply and return temperature. |
| F.024 | The water heats up faster than expected. |
| F.025 | Excessive temperature in the combustion gases. |
| F.027 | The control detects flame with the burner off. |
| F.028 | The ignition fails to confirm the presence of a flame. |
| F.029 | The flame goes out during operation and the ignition fails. |
| F.032 | The fan is spinning outside the allowed range. |
| F.035 | An obstruction in the air or flue gas path is detected. |
| F.040 | The regulation detects an insufficient excess air factor. |
| F.042 | The coding of the device or the gas group is not valid. |
| F.044 | Insufficient ionization signal and failure of its adaptation. |
| F.047 | Incoherent reading from the domestic hot water sensor at the outlet of the internal accumulator. |
| F.049 | Electrical problem in eBUS: short circuit or incompatible polarity between active sources. |
| F.057 | The combustion control is faulty, including its emergency mode. |
| F.061 | The electronic control does not respond within the expected times. |
| F.062 | The flame outage is detected too late. |
| F.063 | Fault when checking the reading and writing of the EEPROM memory. |
| F.064 | The electronics do not correctly convert the signal from a sensor. |
| F.065 | An electronic component exceeds its operating thermal margin. |
| F.067 | Faulty operation warning of the flame control. |
| F.068 | The flame reading is unstable. |
| F.070 | Missing, incorrect, or incompatible DSN identification with the coding. |
| F.071 | The supply temperature reading is not consistent. |
| F.072 | Invalid variation between the supply and return temperature readings. |
| F.073 | Short circuit in the water pressure sensor. |
| F.074 | Interruption of the signal that measures the water pressure. |
| F.075 | The pressure barely increases when starting the heating pump. |
| F.076 | The thermal protection of the main heat exchanger is activated. |
| F.077 | The condensate pump or the flue damper prevents the burner from operating. |
| F.078 | The device does not support the installed control module. |
| F.080 | Anomaly in the cold water sensor of the internal accumulator. |
| F.081 | Fault in the supercharging process described by the manufacturer. |
| F.083 | After starting the burner, the temperature does not rise or does so too slowly. |
| F.084 | The supply and return temperatures show an inconsistent difference. |
| F.085 | The equipment detects an incorrect placement of the NTC sensors. |
| F.087 | There is a missing connection between the ignition transformer and the PCB. |
| F.088 | The electrical connection of the gas valve is lost. |
| F.089 | The integrated pump does not match the model identified by the device. |
| F.092 | The gas type adaptation has not been completed correctly. |
| F.095 | The gas valve actuator reaches its minimum step limit. |
| F.096 | The gas valve actuator reaches its maximum step limit. |
| F.105 | The adaptation of the gas valve requires inspection after replacing control components. |
| F.194 | Fault in the power supply of the PCB. |
| F.195 | The supply voltage drops significantly. |
| F.196 | The supply voltage increases significantly. |
| F.317 | The reading of the domestic hot water flow is not coherent. |
| F.318 | The three-way motorized valve does not move. |
| F.320 | The pump remains locked after the automatic unlocking attempt. |
| F.321 | Electronic fault warning in the pump. |
| F.322 | The pump overheats and the emergency mode does not reduce its temperature. |
| F.323 | Pump operation detected without water. |
| F.324 | The electrical connection of the pumps is interrupted. |
| F.325 | The control detects a fault in the heating pump. |
| F.326 | The hydraulic test detects at least two components that are not functioning. |
| F.327 | The lack of connection of the sanitary circuit limits the minimum flow of heating. |
| F.344 | The control indicates that the regulation electrode can no longer be used. |
| F.346 | The ignition fails with a sudden start condition. |
| F.363 | Memory read or write error on the display. |
| F.390 | Initialization does not complete after updating the software. |
| F.707 | The screen and the PCB are unable to communicate. |
| F.905 | The interface loses communication with the CIM module. |
No matches found. Please check the code and the version of the equipment.
Symptoms without code
If there is a lack of hot water, it does not heat or loses pressure without displaying a warning, describe when it occurs and if there was an intervention or supply cut. The absence of a fault code does not rule out a fault; it also does not allow attributing it to the PCB, a pump, or a sensor.
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Frequently asked questions: this generation
No. This page documents the MA36-CF/1 N-INT and the appliance references indicated above.
No. Describe a start-up without flame confirmation, which can be due to different causes. The part is determined after checking the appliance.
This boiler in the catalog
Saunier Duval Isofast Condens MA 36-CF/1-CfI boiler (n-int)
Manual and documentation
Saunier Duval IsoFast H-Condens
Document editing
Edition 0020298498_00 (04/22/2021), identifying N-INT. Copy of the manufacturer's document retrieved from a public archive; it is not presented as the latest edition.