List of error codes for the De Dietrich HPI Evolution air-to-water heat pump
List of indoor unit error codes – De Dietrich HPI Evolution – AWHP-2 MIT-IN-2 iSystem
| Code | Messages | Description | VéCheck / solution |
| B00 | BL.PSU ERROR | The PSU electronic board is misconfigured | Parameter error on the PSU electronic board
Set the generator type again in the menu #CONFIGURATION (Refer to the original rating plate) |
| B02 | BL.S.DEPART | The MIT-2 flow sensor is short-circuited or has an open circuit. | Poor connection.
Check the wiring between the PCU electronic board and the sensor. Check that the SU electronic board is properly in place. Check that the sensor was fitted correctly. Check the sensor’s resistance. |
| B08 | BL.ENT.BL OUV. | The BL input on the PCU electronic board’s terminal block is open. No frost protection. | The contact connected to the BL input is open.
Check the contact on the BL. |
| input
Parameter error. Check the E.BL. |
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| parameter
Poor connection. Check the wiring. |
| Code | Messages | Description | VéCheck / solution |
| B09 | BL.ENT.BL OUV. | The BL input on the PCU electronic board’s terminal block is open. Frost protection active. | The contact connected to the BL input is open.
Check the contact on the BL. |
| input
Parameter error. Check the E.BL |
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| parameter
Poor connection. Check the wiring. |
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| B10 | BL.GROUPE.EXT | Outdoor unit fault. | Refer to the error codes specific to
the outdoor module. |
| B11 | BL.COM SCU | Communication error with the SCU electronic board. | Poor connection
Check the wiring |
| SCU electronic board not installed in the unit
Install an SCU electronic board |
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| B12 | BL.MANQUE EAU | Water pressure is below 0.5 bar | Lack of water in the circuit.
Add water to the system. |
| B13 | BL.S.ECS | The DHW tank sensor is disconnected or short-circuited | Check that the sensor is properly connected to the S.ECS input on the PCU
Check the wiring Check the sensor’s resistance value. Replace it if necessary |
| B14 | BL.S.EXT | The outdoor sensor is disconnected or short-circuited. | Check that the sensor is properly connected to the S.EXT input on the PCU
Check the wiring Check the sensor’s resistance value. Replace it if necessary |
| B17 | BL.PCU ERROR | The parameters stored on the PCU electronic board are corrupted. | Parameter error on the PCU electronic board.
Replace the PCU electronic board. |
| B18 | BL.MAUVAIS PSU | The PSU electronic board is not recognized | Wrong PSU electronic board for this heat pump.
Replace the PSU electronic board. |
| B19 | BL.PAS DE CONFIG | The indoor module is not configured. | The PCU electronic board has been replaced.
Set the generator type again in the menu #CONFIGURATION (Refer to the original rating plate). |
| B39 | BL.DEBIT | Low flow. | Check the heat pump’s circulator pump setting.
Check that the filter is not clogged. |
| B40 | BL.DEBIT.ARRET | Flow fault. | Check the heat pump’s circulator pump setting.
Check that the filter is not clogged. |
| B41 | BL.COM.CPT.kWh | Communication error with the energy metering option board. | Poor connection
Check the wiring |
| B50 | BL.S.DEP.CPT.kWh | Energy metering flow sensor fault. | Check the sensor’s connection and
resistance |
| B51 | BL.S.RET.CPT.kWh | Energy metering return sensor fault. | Check the sensor’s connection and
resistance |
| B52 | BL.CPT.kWh.ELEC1 | ELEC 1 electric meter fault. | Check that the ELEC1 input is not
short-circuited |
| B53 | BL.CPT.kWh.ELEC2 | ELEC 2 electric meter fault. | Check that the ELEC2 input is not
short-circuited |
| B54 | BL.CPT.kWh.THERM | Thermal meter fault. | Check that the THERM input is not
short-circuited |
| Code | Messages | Description | VéCheck / solution |
| B55 | BL.DEBIT | Low flow. | Check the heat pump’s circulator pump setting.
Check that the filter is not clogged. |
| M04 | SERVICE | A service visit is requested. | The scheduled service date has been reached.
Have the heat pump serviced. To clear the service reminder, set a new date in the #SERVICE menu or set the SERVICE TYPEparameter to NO. |
| SEC.CHAP.BXXJOURS | Screed drying is active.
XX DAYS = Number of screed drying days remaining. |
Screed drying is in progress. Heating for the circuits not involved is switched off.
Wait until the number of days shown reaches 0. Set the SCREED DRYING parameter to NO. |
|
| SEC.CHAP.CXXJOURS | |||
| SEC.CHAP.B+C XX DAYS | |||
| M23 | CHANGE OUTDOOR SENSOR | The outdoor sensor is faulty. | Replace the wireless outdoor sensor. |
| Code | Messages | Description | VéCheck / solution |
| B00 | BL.PSU ERROR | The PSU electronic board is misconfigured | Parameter error on the PSU electronic board
Contact the professional in charge of main taining the unit |
| B02 | BL.S.DEPART | The MIT-2 flow sensor is short-circuited or has an open circuit. | Faulty connection.
Contact the professional in charge of main taining the unit. |
| B08 | BL.ENT.BL OUV. | The BL input on the PCU electronic board’s terminal block is open. No frost protection. | The contact connected to the BL input is open.
Contact the professional in charge of main taining the unit. |
| Parameter error.
Contact the professional in charge of main taining the unit. |
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| Faulty connection.
Contact the professional in charge of main taining the unit. |
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| B09 | BL.ENT.BL OUV. | The BL input on the PCU electronic board’s terminal block is open. Frost protection. | The contact connected to the BL input is open.
Contact the professional in charge of main taining the unit. |
| Parameter error.
Contact the professional in charge of main taining the unit. |
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| Faulty connection.
Contact the professional in charge of main taining the unit. |
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| B10 | BL.GROUPE.EXT | Outdoor unit fault. | Contact the professional in charge of main
taining the unit. |
| B11 | BL.COM SCU | Communication error with the SCU electronic board. | Contact the professional in charge of main
taining the unit. |
| B12 | BL.MANQUE EAU | Water pressure is below 0.5 bar | Lack of water in the circuit.
Add water to the system. |
| B13 | BL.S.ECS | The DHW tank sensor is disconnected or short-circuited | Faulty connection.
Contact the professional in charge of main taining the unit. |
| Code | Messages | Description | VéCheck / solution |
| B14 | BL.S.EXT | The outdoor sensor is disconnected or short-circuited. | Faulty connection.
Contact the professional in charge of main taining the unit. |
| B17 | BL.PCU ERROR | The parameters stored on the PCU electronic board are corrupted. | Parameter error on the PCU electronic board.
Contact the professional in charge of main taining the unit. |
| B18 | BL.MAUVAIS PSU | The PSU electronic board is not recognized | Wrong PSU electronic board for this heat pump.
Contact the professional in charge of main taining the unit. |
| B19 | BL.PAS DE CONFIG | The indoor module is not configured. | The PSU electronic board has been replaced.
Contact the professional in charge of main taining the unit. |
| B39 | BL.DEBIT | Low flow. | Contact the professional in charge of main
taining the unit. |
| B40 | BL.DEBIT.ARRET | Flow fault. | Contact the professional in charge of main
taining the unit. |
| B41 | BL.COM.CPT.kWh | Communication error with the energy metering option board. | Faulty connection.
Contact the professional in charge of main taining the unit. |
| B50 | BL.S.DEP.CPT.kWh | Energy metering flow sensor fault. | Faulty connection.
Contact the professional in charge of main taining the unit. |
| B51 | BL.S.RET.CPT.kWh | Energy metering return sensor fault. | Faulty connection.
Contact the professional in charge of main taining the unit. |
| B52 | BL.CPT.kWh.ELEC1 | ELEC 1 electric meter fault. | Faulty connection.
Contact the professional in charge of main taining the unit. |
| B53 | BL.CPT.kWh.ELEC2 | ELEC 2 electric meter fault. | Faulty connection.
Contact the professional in charge of main taining the unit. |
| B54 | BL.CPT.kWh.THERM | Thermal meter fault. | Faulty connection.
Contact the professional in charge of main taining the unit. |
| B55 | BL.DEBIT | Low flow. | Contact the professional in charge of main
taining the unit. |
| M04 | REVISION | A service check is requested. | The scheduled service date has been reached.
Perform maintenance on the heat pump. To clear the service reminder, set another date in the #REVISION menu, or set the TYPE REVISION parameter to NO. |
| SEC.CHAP.BXXJOURS | Screed drying is active.
XX DAYS = Number of screed drying days remaining. |
Screed drying is in progress. Heating for the circuits not involved is turned off.
Wait until the displayed number of days reaches 0. Set the SECHAGE CHAPE parameter to NO. |
|
| SEC.CHAP.CXXJOURS | |||
| SEC.CHAP.B+C XX DAYS | |||
| M23 | CHANGE OUTDOOR SENSOR | The outdoor sensor is faulty. | Replace the wireless outdoor sensor. |
Défaults (code type Lxx or Dxx)
| Code | Défaults | Source of the
défault |
Description | VéCheck / solution |
| D03 D04 | DEF.S.DEP.B DEF.S.DEP.C | SCU | Circuit B flow sensor fault Circuit C flow sensor fault Notes:
The circuit pump is running. The circuit’s 3-way valve motor is no longer powered and can be operated manually. |
Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| D05 | DEF.S.EXT. | SCU | Outdoor sensor fault Notes:
The setpoint is equal to the parameter MAX MIT. Valve regulation is no longer ensured, but monitoring of the maximum circuit temperature after the valve is still ensured. The valves can be operated manually. Domestic hot water heating is still ensured. |
Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| D07 | DEF.S.SYST. | SCU | System sensor fault | Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| Code | Défaults | Source of the
défault |
Description | VéCheck / solution |
| D09 | DEF.S.ECS | SCU | Domestic hot water sensor fault
Notes: Domestic hot water heating is no longer ensured. The loading pump is running. The tank’s loading temperature is equal to the indoor module’s temperature. |
Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| D11 D12 D13 | DEF.S.AMB.A DEF.S.AMB.B DEF.S.AMB.C | SCU | Room sensor A fault Room sensor B fault Room sensor C fault Notes:
The affected circuit operates without input from the room sensor. |
Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| D14 | DEF.COM MC | SCU | Communication failure between the SCU electronic board and the radio module | Poor connection
Check the connection and the connectors |
| Boiler module failure
Replace the boiler module |
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| D15 | DEF.S.BAL.TP | SCU | Buffer tank sensor fault Note:
Buffer tank heating is no longer ensured. |
Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| D16 D16 | DEF.S.PISC.B DEF.S.PISC.C | SCU | Pool sensor fault circuit B Pool sensor fault circuit C Notes:
Pool heating runs continuously during the comfort period of the circuit |
Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| D17 | DEF.S.BAL.2 | SCU | Tank 2 sensor fault | Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| D18 | DEF.S.BAL.SOL. | SCU | Solar tank sensor fault | Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| D19 | DEF.S.COL.SOL. | SCU | Collector sensor fault | Poor connection Sensor failure
Contact the professional responsible for maintaining the unit |
| D20 | DEF.COM.SOL. | SCU | Communication failure between the SCU electronic board and the solar controller
Contact the professional responsible for maintaining the unit |
|
| D27 | DEF.COM.PCU | SCU | Communication failure between the SCU electronic board and the solar controller
Contact the professional responsible for maintaining the unit |
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| D32 | 5 RESET:ON/OFF | SCU | 5 resets have been performed in less than one hour
Turn the heat pump off and back on |
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| Code | Défaults | Source of the
défault |
Description | VéCheck / solution |
| D37 | TA-S COURT-CIR | SCU | The Titan Active System® is short-circuited
Check that the cable connecting the SCU electronic board and the anode is not short-circuited Check that the anode is not short-circuited Notes: Domestic hot water production has stopped but can still be restarted using the button. The tank is no longer protected. If a tank without Titan Active System® is connected to the heat pump, check that the TAS simulation connector (supplied in the AD212 kit) is installed on the sensor board. |
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| D38 | TA-S DEBRANCHE | SCU | The Titan Active System® circuit is open
Check that the cable connecting the SCU electronic board and the anode is not cut Check that the anode is not broken Notes: Domestic hot water production has stopped but can still be restarted using the button. The tank is no longer protected. If a tank without Titan Active System® is connected to the heat pump, check that the TAS simulation connector (supplied in the AD212 kit) is installed on the sensor board. |
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| D99 | DEF.MAUVAIS.PCU | The SCU software version does not recognize the connected PCU
Contact the professional responsible for maintaining the unit |
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| L33 | DEF.DEBIT | The flow is below the threshold set by the parameter DEBIT.MIN.STOP
Contact the professional responsible for maintaining the unit |
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