Here we have detailed the possible reasons that specific fault codes may be appearing on your Viessmann boiler. Depending on which Viessmann boiler you have, the diagnosis for the code appearing may differ. In order to correctly diagnose the fault your Viessmann boiler is experiencing, we always recommend contacting a Viessmann Trained Installer.


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Fault Code 0b
Fault Code 0C
Fault Code 0F
Fault Code 10
Fault Code 10, 14, F3, and F4
Fault Code 18 and D1
Fault Code 19 
Fault Code 20
Fault Code 21
Fault Code 28
Fault Code 29, 41, 49, F80, F81, F83, F88 and F89
Fault Code 30
Fault Code 38
Fault Code 40 and 44
Fault Code 41
Fault Code 48 and 4C
Fault Code 50, 51, 58 and 59
Fault Code 52
Fault Code 55, 56 and 57
Fault Code 5A, B7, and B8
Fault Code 5C, 5D, 5E and 5F
Fault Code 60, 68, 70, 78, BD, BE and BF
Fault Code 80, 81, 82, 83 and FD
Fault Code 8C, 8D, 8E and 8F
Fault Code 88, 89, and E6
Fault Code 90, 91, 92, 93, 94, 98, 99, 9A, 9B , 9C, 9E, 9F and AB
Fault Code D4
Fault Code D5
Fault Code A0, A1, A2, AA, and AC
Fault Code A3, B0, F1, F-E1 and F-E2
Fault Code A4
Fault Code FA and FB
Fault Code A7
Fault Code A8
Fault Code A9, BA, BB, BC and FE0
Fault Code AD
Fault Code B1
Fault Code B2
Fault Code B3 and E5
Fault Code B4
Fault Code B5
Fault Code B6
Fault Code B9, ED, F0, F-E5, F-EC, F-ED, F-EE, F-EF, F-FD and F-FF
Fault Code C1
Fault Code C2-C8, CD-CF, D2-D8, DA-DF, and E0
Fault Code C9, CA and CB
Fault Code CC and F0
Fault Code E1, E7, E8, E9, EA, EB, EC and FF2
Fault Code E2 and E3
Fault Code E4
Fault Code EE and EF
Fault Code F5
Fault Code F6, 58, F9, F-E1, F-E2 and F-F6
Fault Code F-B7, F-F4, F-F2, F-F7, F-F8 and F-F9
Fault Code FC
Fault Code FE
Fault Code FE4
 Fault Code F-FA, F-FB and FR

Fault Code 0b

Listed below are the possible faults for the fault code 0b.

   


Boiler Model


System Behaviour


Diagnosis

Vitodens 200

The burner control switches to lockout. The fan does not idle after auto reset (incorrect fan rpm).

Severe wind conditions in the vent system

Vitodens 100-W

Burner blocked

Insufficient water flow. Incorrect flow direction. Defective flow switch.(Blockage)

Fault Code 0C

Listed below are the possible faults for the fault code 0C.

Boiler Model

System Behaviour

Diagnosis

Vitodens 100-W

Burner blocked

Insufficient power supply

Vitodens 200

Burner control switches to lockout

Flame signal still present after switching off

Fault Code 0F

Listed below are the possible faults for the fault code 0F.

Boiler Model

System Behaviour

Diagnosis

Vitodens 222-F

Control mode

Code "0F" is only displayed in the fault history(service required)

Vitotronic 300 / Vitotronic 300-K, with Vitotronic 300 / Vitodens 200-W / Vitocontrol-S, with Vitotronic 100

Control mode / Controlled operation

Service required. "0F" is only displayed in the fault history.

Vitotronic 200 / 300

Normal operation

Service required

Vitocontrol-S, MW1 with Vitotronic 100 / Vitotronic 300-K, MW1S with Vitotronic 100

Control mode

Maintenance "0F" is only displayed in the fault history

Fault Code 10

Listed below are the possible faults for the fault code 10.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200-W / 222-F / Vitotronic 300 / 200/ 200-H / 050/200-H / 300-K / vitocontrol-S

Boiler operates based on outdoor temperature of 32°F / 0°C

Short circuit – Outdoor temperature sensor

Vitotronic 300-K, MW2S with Vitotronic 100 / Vitodens 100-W (combiPLUS) / 200-w / Vitocontrol-S, WB2B with Vitotronic 100

Controls as if the outdoor temperature / Constant Mode

Outdoor temperature sensor shorted out


Fault Code 10, 14, F3, and F4

Listed below are the possible faults for the fault code 10, 14, F3 and F4.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Burner control switches to lockout

No flame signal is present


Fault Code 18 and D1

Listed below are the possible faults for the fault code 80, 81, 82, 83 and F.

Boiler Model

System Behaviour

Diagnosis

Vitodens 100 / 200-W / 222-F / Vitotronic 300-K With 100 / Vitocontrol-S

Boiler operates based on outdoor temperature of 32°F / 0°C / Constant Mode

Outdoor temperature sensor cable broken

Vitotronic / 100 / 200 / 300 / 050/200-H /300-K / Vitocontrol-S, MW1 with Vitotronic 100

Operates on basis of 32°F / 0°C outdoor temperature

Open circuit – Outdoor temperature sensor

Vitotronic 200-H / Vitotronic 300-K, MW1B with Vitotronic 300 / Vitotronic 300-K, MW2B with Vitotronic 200

Controls as if the outdoor temperature

Lead break, Outdoor temperature sensor

Vitotronic 050/200-H

Activates after 0°C / 32°F outdoor temperature

Cable break – Outdoor temperature sensor

Vitodens 100-W

Burner in fault mode

DIP switch S2 is set to "ON"


Fault Code 19

Listed below are the possible faults for the fault code 19.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300

Activates after 0°C / 32°F outdoor temperature

Communication fault, Wireless Outdoor temperature sensor


Fault Code 20

Listed below are the possible faults for the fault code 20.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 300 / 300-K / 200 / 100

Stand-alone control unit without supply temperature sensor (possibly supply temperature not high enough)

short circuit – Common supply temperature sensor

Vitocontrol-S with Vitotronic 100 / Vitotronic 300-K, with Vitotronic 200

Vitocontrol-S, controls in a stand-alone manner w/o supply temperature sensor (supply temperature may not be high enough)

Common supply temperature sensor shorted out

Vitocrossal 300

Regulates without supply temperature sensor (low-loss header)

Short circuit – System Flow temperature sensor

Vitodens 200-W / 222-F

Regulates without supply temperature sensor (low-loss header)

Short circuit – System supply temperature sensor

Vitotronic 050/200-H< / 200 / 200-H / 300

Mixing valve closes/ closed

Short circuit – Supply temperature sensor / mixing valve circuit M1

Vitotronic 300-K, with Vitotronic 100

Vitotronic 300-K, MW1S controls in a stand-alone manner w/o strap-on sensor (supply temperature may not be high enough)

Short circuit – Strap-on temperature sensor

Vitodens 200-W

Regulates without supply temperature sensor (low-loss header)

System supply temperature sensor shorted out


Fault Code 21

Listed below are the possible faults for the fault code 21.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 200 / 300

operation without influence of return water temperature

Short circuit – Return water temperature sensor


Fault Code 28

Listed below are the possible faults for the fault code 28.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100

Vitocontrol-S, VD2/CT3/CM2 controls in a stand-alone manner w/o supply temperature sensor (supply temperature may not be high enough)

Open circuit – Common supply temperature sensor

Vitocontrol-S with Vitotronic 100 / Vitotronic 300-K,with Vitotronic 100

Vitocontrol-S, WB2B controls in a stand-alone manner w/o supply temperature sensor (supply temperature may not be high enough)

Common supply temperature sensor cable broken

Vitocrossal 300 / Vitodens 200-W / 22-F

Regulates without supply temperature sensor (low-loss header)

System supply temperature sensor cable broken

Vitotronic 050/200-H

Mixing valve closes

Cable break – Supply temperature sensor

Vitotronic 050/200-H

Mixing valve is closed

Open circuit – Supply temperature sensor of mixing valve circuit M1

Vitotronic 200-H / Vitotronic 200 / 300

Mixing valve is being closed

Lead break, Supply temperature sensor, heating circuit with mixing valve M1 (heating circuit 1)

Vitotronic 300 Vitotronic / 300-K with Vitotronic 300 / 200

Stand-alone control unit without supply temperature sensor (possibly supply temperature not high enough)

Lead break, Common supply temperature sensor

Vitotronic 300-K with Vitotronic 100

Vitotronic 300-K, MW1S controls in a stand-alone manner w/o strap-on sensor (supply temperature may not be high enough)

Open circuit – Strap-on temperature sensor

 

Fault Code 29, 41, 49, F-80, F-81, F-83, F-88 and F-89

Listed below are the possible faults for the fault code 29, 41, 49, F-80, F-81, F-83, F-88 and F-89.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 200 / 300

Normal operation without influence of return water temperature

Open circuit 1 or 2 – Return water temperature sensor (of mixing valve circuit 1)

Fault Code 30

Listed below are the possible faults for the fault code 30.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S, with Vitotronic 100 / Vitocrossal 300 / Vitodens 200-W / 222-F / Vitotronic 100 / 200 / 300

Burner is started and stopped via an adjustable high limit

Short circuit – Boiler water temperature sensor

Vitocontrol-S with Vitotronic 100 / Vitodens 100-W (CombiPLUS)/ 200-1

Burner blocked

Boiler water temperature sensor shorted out

Fault Code 38

Listed below are the possible faults for the fault code 38.

Boiler Model

System Behaviour

Diagnosis

Vitodens – 200-W / 222-F / COMBIPLUS

Burner blocked

Boiler water temperature sensor cable broken

Vitotronic 100 / 200 / 300 / Vitocontrol-S with Vitotronic 100

Burner is switched on and off by the adjustable high limit

Open circuit – Boiler temperature sensor

Vitotronic 300-K with Vitotronic 300 / Vitotronic 300-K with Vitotronic 300

The burner is started and stopped via a temperature controller

Lead break, Boiler water temperature sensor

Vitodens 100-W

Burner blocked

Boiler water temperature sensor lead broken


Fault Code 40 and 44

Listed below are the possible faults for the fault code 40 and 44.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Mixing valve closes

Heating circuit 2 with mixing valve supply short circuit on temperature sensor


Fault Code 41

Listed below are the possible faults for the fault code 41.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300

Operation without accounting for return water temperature

Short circuit – Return water temperature sensor of mixing valve circuit 2


Fault Code 48 and 4C

Listed below are the possible faults for the fault code 48 and 4C.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Mixing valve closes / Closed

Heating circuit 2 with mixing valve supply temperature sensor cable broken / open circuit


Fault Code 50, 51, 58 and 59

Listed below are the possible faults for the fault code 50, 51, 58 and 59

Boiler Model

System Behaviour

Diagnosis

Vitodens 200-W / 222-F

No DHW heating/ Fault with DHW

Short circuit/open circuit – DHW tank temperature sensor or lead break

Fault Code 52

Listed below are the possible faults for the fault code 52

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300

Control mode

Short circuit – Supply temperature sensor low-loss header

Vitodens 100-W CombiPLUS

Burner blocked (with CombiPLUS only)

Flow sensor shorted out (in CombiPLUS)


Fault Code 55, 56 and 57

Listed below are the possible faults for the fault code 55, 56 and 57.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300-K, with Vitotronic 200

Control mode

Maintenance or fault on Vitotronic 100 of boiler 5-8


Fault Code 5A, B7, and B8

Listed below are the possible faults for the fault code 5A, B7 and B8.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Lead break, low-loss header Supply temperature sensor

All Viessmann boilers

Burner blocked / control mode

sensor cable broken



Fault Code 5C, 5D, 5E and 5F

Listed below are the possible faults for the fault code 5C, 5D, 5E and 5F.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300-K with Vitotronic 200

Control mode

Communication fault, Vitotronic 100 of boiler 5-8

Fault Code 60, 68, 70, 78, BD, BE and BF

Listed below are the possible faults for the fault code 60, 68, 70, 78, BD, BE and BF.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

– No output reduction

– Return control open

– Boiler with maximum temperature

Short/open circuit – Temperature sensor [17A]

Fault Code 80, 81, 82, 83 and F

Listed below are the possible faults for the fault code 80, 81, 82, 83 and F.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner control unit in a fault state; system cools down; burner control unit locked out

Short circuit – Boiler water temperature sensor, burner control unit

Fault Code 88, 89, and E6

Listed below are the possible faults for the fault code 88, 89, and E6.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300

Burner control unit in a fault state

Lead break, Boiler water temperature sensor, burner control unit

Fault Code 8C, 8D, 8E and 8F

Listed below are the possible faults for the fault code 8C, 8D, 8E and 8F.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 300-K with Vitotronic 100 / 200

Control mode

Communication fault, Vitotronic 100 of boiler 1-4

Fault Code 90, 91, 92, 93, 94, 98, 99, 9A, 9B , 9C, 9E, 9F and AB

Listed below are the possible faults for the fault code 90, 91, 92, 93, 94, 98, 99, 9A, 9B , 9C 9E, 9F and AB.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Short circuit – Temperature sensor [5] / [6] / [7] / [10]

Fault Code A0, A1, A2, AA, and AC

Listed below are the possible faults for the fault code A0, A1, A2, AA, and AC.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300 / Vitotronic 300-K with Vitotronic 300

Boiler cools down

Fault, safety equipment at " X2 / X3 / X7″ of plug-in adaptor 2 for external safety equipment

Vitodens 200

Boiler operates in emergency mode (after approx. 30 min. BUS fault)

OR

Boiler cools down

Internal BUS fault

OR

Open circuit – Internal BUS connection

Fault Code A3, B0, F1, F-E1 and F-E2

Listed below are the possible faults for the fault code A3, B0, F1, F-E1 and F-E2.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner blocked

Flue gas temperature sensor not properly positioned / Check Sensor

External pump fitted on the system(100-w) A-3 fault.

Fault Code A4

Listed below are the possible faults for the fault code A4.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Pump runs at maximum speed

Open circuit – BUS connection with variable speed heating circuit pump

Fault Code A7

Listed below are the possible faults for the fault code A7.

Boiler Model

System Behaviour

Diagnosis

Vitocrossal 300 / Vitodens 200-W / 222-F / 300

Control mode (stays in factory default setting)

Faulty Programming unit

Fault Code A8

Listed below are the possible faults for the fault code A8.

Boiler Model

System Behaviour

Diagnosis

Vitodens 222-F

Burner blocked. The venting program is started automatically

Air lock in the Internal circulation pump or minimum flow rate not achieved

Fault Code A9, BA, BB, BC and F-E0

Listed below are the possible faults for the fault code A9, BA, BB, BC and F-E0.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control Mode

Communication fault

Fault Code AD

Listed below are the possible faults for the fault code AD.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 100 / Vitotronic 300-K with Vitotronic 300

Control mode

Isolation valve configuration fault: Coding OC:2, OC:3 or OC:4 set, and coding 4E:1 not set

Fault Code B1

Listed below are the possible faults for the fault code B1.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Communication fault, Programming unit

Fault Code B2

Listed below are the possible faults for the fault code B1.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Boiler cools down

Sensor inputs are not read correctly

Fault Code B3 and E5

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Setting via service level not possible

Data points are not stored; internal fault VR20

Fault Code B4

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 100 / 200 / 300 / Vitotronic 300-K with Vitotronic 100

Emissions test mode

Internal electronics fault

Vitocontrol-S with Vitotronic 100 / Vitodens 200-W

Regulates as if the outside temperature was 32°F (0°C)

Internal fault

Vitotronic 050/200-H

Undefined control characteristics

Internal electronics fault

Fault Code B5

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Internal electronics fault

Fault Code B6

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Constant mode

Invalid hardware recognised

Fault Code B9, ED, F0, FE, FD and FF

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Normal operation / fault around burner control unit

Internal fault (PCB)

Fault Code C1

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control Mode

External safety equipment

Fault Code C2-C8, CD-CF, D2-D8, DA-DF, and E0

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Open circuit – KM BUS to solar control unit / Extension AM1 / DE1-DE3 M1 / communication fault

Fault Code C9, CA and CB

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 100 / 300 / Vitotronic 300-K with Vitotronic 300

Boiler cools down

fault: Maximum pressure limiter 1 2

Fault Code CC and F0

Listed below are the possible faults for the fault code CC and F0.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Burner control unit switches to lockout (due to large line voltage fluctuations)

Differential air pressure sensor / open circuit

Fault Code D4

Listed below are the possible faults for the fault code D4.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Boiler cools down

Fixed high limit has responded or fuse F2 has blown.

Fault Code D5

Listed below are the possible faults for the fault code D5.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Boiler drives up to electronic maximum limit

Boiler does not log in at the cascade control unit

Fault Code E1, E7, E8, E9, EA, EB, EC and F2

Listed below are the possible faults for the fault code E1, E7, E8, E9, EA, EB, EC and F2.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner in fault mode

Ionisation current too high during calibration

Boiler temperature limiter responded(F2) air or blockage in system/pump failure

Fault Code E2 and E3

Boiler Model

System Behaviour

Diagnosis

Vitodens 200-W / 222-F / Vitotronic 300

Burner in fault mode

Heating water flow rate too low during calibration; flow switch caused shutdown

Fault Code E4

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner blocked

Fault, supply voltage 24V

Fault Code EE and EF

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitocrossal 300 / Vitodens 200-W / 222-F / Vitotronic 300

Burner in fault mode

At burner start, flame signal is missing or too weak

     

Fault Code F5

Boiler Model

System Behaviour

Diagnosis

Vitodens 100-W / 200 / 0 / Vitotronic 300

Burner blocked

Faulty Air pressure switch.

Air damper(flap)stuck

     

Fault Code F6, 58, F9, F-E1, F-E2 and F-F6

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Gas pressure switch shows no gas pressure / Electrical connection fault

Gas shut-off valve closed; gas pressure switch faulty; multiple problems with gas supply

Fault Code FA and FB

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner in fault mode / Emergency operation

Fan not at standstill / plug-in connection

Fault Code F-B7, F-F4, F-F2, F-F7, F-F8 and F-F9

Boiler Model

System Behaviour

Diagnosis

Vitocrossal 200

Case A: Burner control unit in a fault state; system cools down; burner control unit locked out.

Case B: Type of coding card

Case A: Coding card not inserted in the burner control unit; incorrect or faulty coding card.

Case B: Coding card does not match burner control unit.

Fault Code FC

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner in fault mode

Gas valve faulty or faulty modulation valve control; or vent system blocked.

Check fan, fan cable, PCB

Fault Code FE

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner blocked or in fault mode

Strong interference (EMC) field nearby, or Faulty main PCB

Fault Code F-E4

Boiler Model

System Behaviour

Diagnosis

Vitocrossal 200

Burner shuts down

Multiple detection of undervoltage

Fault Code F-FA, F-FB and FR

Boiler Model

System Behaviour

Diagnosis

Vitocrossal 200 / 400-620 / 186-311

Fan runs without demand; Burner control unit in a fault state

Fan has not stopped; cable [100A] faulty; fan faulty; burner control unit faulty

Fault Code 0B

Listed below are the possible faults for the fault code 0B.

   


Boiler Model


System Behaviour


Diagnosis

Vitodens 200

The burner control switches to lockout. The fan does not idle after auto reset (incorrect fan rpm).

Severe wind conditions in the vent system

Vitodens 100-W

Burner blocked

Insufficient water flow. Incorrect flow direction. Defective flow switch.

Fault Code 0C

Listed below are the possible faults for the fault code 0C.

Boiler Model

System Behaviour

Diagnosis

Vitodens 100-W

Burner blocked

Insufficient power supply

Vitodens 200

Burner control switches to lockout

Flame signal still present after switching off

Fault Code 0F

Listed below are the possible faults for the fault code 0F.

Boiler Model

System Behaviour

Diagnosis

Vitodens 222-F

Control mode

Code "0F" is only displayed in the fault history

Vitotronic 300 / Vitotronic 300-K, with Vitotronic 300 / Vitodens 200-W / Vitocontrol-S, with Vitotronic 100

Control mode / Controlled operation

Service required. "0F" is only displayed in the fault history.

Vitotronic 200 / 300

Normal operation

Service required

Vitocontrol-S, MW1 with Vitotronic 100 / Vitotronic 300-K, MW1S with Vitotronic 100

Control mode

Maintenance "0F" is only displayed in the fault history

Fault Code 10

Listed below are the possible faults for the fault code 10.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200-W / 222-F / Vitotronic 300 / 200/ 200-H / 050/200-H / 300-K / vitocontrol-S

Boiler operates based on outdoor temperature of 32°F / 0°C

Short circuit – Outdoor temperature sensor

Vitotronic 300-K, MW2S with Vitotronic 100 / Vitodens 100-W (combiPLUS) / 200-w / Vitocontrol-S, WB2B with Vitotronic 100

Controls as if the outdoor temperature / Constant Mode

Outdoor temperature sensor shorted out


Fault Code 10, 14, F3, and F4

Listed below are the possible faults for the fault code 10, 14, F3 and F4.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Burner control switches to lockout

No flame signal is present


Fault Code 18 and D1

Listed below are the possible faults for the fault code 80, 81, 82, 83 and F.

Boiler Model

System Behaviour

Diagnosis

Vitodens 100 / 200-W / 222-F / Vitotronic 300-K With 100 / Vitocontrol-S

Boiler operates based on outdoor temperature of 32°F / 0°C / Constant Mode

Outdoor temperature sensor cable broken

Vitotronic / 100 / 200 / 300 / 050/200-H /300-K / Vitocontrol-S, MW1 with Vitotronic 100

Operates on basis of 32°F / 0°C outdoor temperature

Open circuit – Outdoor temperature sensor

Vitotronic 200-H / Vitotronic 300-K, MW1B with Vitotronic 300 / Vitotronic 300-K, MW2B with Vitotronic 200

Controls as if the outdoor temperature

Lead break, Outdoor temperature sensor

Vitotronic 050/200-H

Activates after 0°C / 32°F outdoor temperature

Cable break – Outdoor temperature sensor

Vitodens 100-W

Burner in fault mode

DIP switch S2 is set to "ON"


Fault Code 19

Listed below are the possible faults for the fault code 19.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300

Activates after 0°C / 32°F outdoor temperature

Communication fault, Wireless Outdoor temperature sensor


Fault Code 20

Listed below are the possible faults for the fault code 20.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 300 / 300-K / 200 / 100

Stand-alone control unit without supply temperature sensor (possibly supply temperature not high enough)

short circuit – Common supply temperature sensor

Vitocontrol-S with Vitotronic 100 / Vitotronic 300-K, with Vitotronic 200

Vitocontrol-S, controls in a stand-alone manner w/o supply temperature sensor (supply temperature may not be high enough)

Common supply temperature sensor shorted out

Vitocrossal 300

Regulates without supply temperature sensor (low-loss header)

Short circuit – System Flow temperature sensor

Vitodens 200-W / 222-F

Regulates without supply temperature sensor (low-loss header)

Short circuit – System supply temperature sensor

Vitotronic 050/200-H< / 200 / 200-H / 300

Mixing valve closes/ closed

Short circuit – Supply temperature sensor / mixing valve circuit M1

Vitotronic 300-K, with Vitotronic 100

Vitotronic 300-K, MW1S controls in a stand-alone manner w/o strap-on sensor (supply temperature may not be high enough)

Short circuit – Strap-on temperature sensor

Vitodens 200-W

Regulates without supply temperature sensor (low-loss header)

System supply temperature sensor shorted out


Fault Code 21

Listed below are the possible faults for the fault code 21.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 200 / 300

operation without influence of return water temperature

Short circuit – Return water temperature sensor


Fault Code 28

Listed below are the possible faults for the fault code 28.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100

Vitocontrol-S, VD2/CT3/CM2 controls in a stand-alone manner w/o supply temperature sensor (supply temperature may not be high enough)

Open circuit – Common supply temperature sensor

Vitocontrol-S with Vitotronic 100 / Vitotronic 300-K,with Vitotronic 100

Vitocontrol-S, WB2B controls in a stand-alone manner w/o supply temperature sensor (supply temperature may not be high enough)

Common supply temperature sensor cable broken

Vitocrossal 300 / Vitodens 200-W / 22-F

Regulates without supply temperature sensor (low-loss header)

System supply temperature sensor cable broken

Vitotronic 050/200-H

Mixing valve closes

Cable break – Supply temperature sensor

Vitotronic 050/200-H

Mixing valve is closed

Open circuit – Supply temperature sensor of mixing valve circuit M1

Vitotronic 200-H / Vitotronic 200 / 300

Mixing valve is being closed

Lead break, Supply temperature sensor, heating circuit with mixing valve M1 (heating circuit 1)

Vitotronic 300 Vitotronic / 300-K with Vitotronic 300 / 200

Stand-alone control unit without supply temperature sensor (possibly supply temperature not high enough)

Lead break, Common supply temperature sensor

Vitotronic 300-K with Vitotronic 100

Vitotronic 300-K, MW1S controls in a stand-alone manner w/o strap-on sensor (supply temperature may not be high enough)

Open circuit – Strap-on temperature sensor

 

Fault Code 29, 41, 49, F80, F81, F83, F88 and F89

Listed below are the possible faults for the fault code 29, 41, 49, F80, F81, F83, F88 and F89.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 200 / 300

Normal operation without influence of return water temperature

Open circuit 1 or 2 – Return water temperature sensor (of mixing valve circuit 1)

Fault Code 30

Listed below are the possible faults for the fault code 30.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S, with Vitotronic 100 / Vitocrossal 300 / Vitodens 200-W / 222-F / Vitotronic 100 / 200 / 300

Burner is started and stopped via an adjustable high limit

Short circuit – Boiler water temperature sensor

Vitocontrol-S with Vitotronic 100 / Vitodens 100-W (CombiPLUS)/ 200-1

Burner blocked

Boiler water temperature sensor shorted out

Fault Code 38

Listed below are the possible faults for the fault code 38.

Boiler Model

System Behaviour

Diagnosis

Vitodens – 200-W / 222-F / COMBIPLUS

Burner blocked

Boiler water temperature sensor cable broken

Vitotronic 100 / 200 / 300 / Vitocontrol-S with Vitotronic 100

Burner is switched on and off by the adjustable high limit

Open circuit – Boiler temperature sensor

Vitotronic 300-K with Vitotronic 300 / Vitotronic 300-K with Vitotronic 300

The burner is started and stopped via a temperature controller

Lead break, Boiler water temperature sensor

Vitodens 100-W

Burner blocked

Boiler water temperature sensor lead broken


Fault Code 40 And 44

Listed below are the possible faults for the fault code 40 and 44.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Mixing valve closes

Heating circuit 2 with mixing valve supply short circuit on temperature sensor


Fault Code 41

Listed below are the possible faults for the fault code 41.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300

Operation without accounting for return water temperature

Short circuit – Return water temperature sensor of mixing valve circuit 2


Fault Code 48 and 4C

Listed below are the possible faults for the fault code 48 and 4C.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Mixing valve closes / Closed

Heating circuit 2 with mixing valve supply temperature sensor cable broken / open circuit


Fault Code 50, 51, 58 and 59

Listed below are the possible faults for the fault code 50, 51, 58 and 59.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200-W / 222-F

No DHW heating/ Fault with DHW

Short circuit/open circuit – DHW tank temperature sensor or lead break

Fault Code 52

Listed below are the possible faults for the fault code 52.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300

Control mode

Short circuit – Supply temperature sensor low-loss header

Vitodens 100-W CombiPLUS

Burner blocked (with CombiPLUS only)

Flow sensor shorted out (in CombiPLUS)


Fault Code 55, 56 and 57

Listed below are the possible faults for the fault code 55, 56 and 57.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300-K, with Vitotronic 200

Control mode

Maintenance or fault on Vitotronic 100 of boiler 5-8


Fault Code 5A, B7, and B8

Listed below are the possible faults for the fault code 5A, B7 and B8.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Lead break, low-loss header Supply temperature sensor

All Viessmann boilers

Burner blocked / control mode

sensor cable broken



Fault Code 5C, 5D, 5E and 5F

Listed below are the possible faults for the fault code 5C, 5D, 5E and 5F.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300-K with Vitotronic 200

Control mode

Communication fault, Vitotronic 100 of boiler 5-8

Fault Code 60, 68, 70, 78, BD, BE and BF

Listed below are the possible faults for the fault code 60, 68, 70, 78, BD, BE and BF.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

– No output reduction

– Return control open

– Boiler with maximum temperature

Short/open circuit – Temperature sensor [17A]

Fault Code 80, 81, 82, 83 and F

Listed below are the possible faults for the fault code 80, 81, 82, 83 and F.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner control unit in a fault state; system cools down; burner control unit locked out

Short circuit – Boiler water temperature sensor, burner control unit

Fault Code 88, 89, and E6

Listed below are the possible faults for the fault code 88, 89, and E6.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300

Burner control unit in a fault state

Lead break, Boiler water temperature sensor, burner control unit

Fault Code 8C, 8D, 8E and 8F

Listed below are the possible faults for the fault code 8C, 8D, 8E and 8F.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 300-K with Vitotronic 100 / 200

Control mode

Communication fault, Vitotronic 100 of boiler 1-4

Fault Code 90, 91, 92, 93, 94, 98, 99, 9A, 9B , 9C, 9E, 9F and AB

Listed below are the possible faults for the fault code 90, 91, 92, 93, 94, 98, 99, 9A, 9B , 9C 9E, 9F and AB.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Short circuit – Temperature sensor [5] / [6] / [7] / [10]

Fault Code A0, A1, A2, AA, and AC

Listed below are the possible faults for the fault code A0, A1, A2, AA, and AC.

Boiler Model

System Behaviour

Diagnosis

Vitotronic 300 / Vitotronic 300-K with Vitotronic 300

Boiler cools down

Fault, safety equipment at " X2 / X3 / X7″ of plug-in adaptor 2 for external safety equipment

Vitodens 200

Boiler operates in emergency mode (after approx. 30 min. BUS fault)

OR

Boiler cools down

Internal BUS fault

OR

Open circuit – Internal BUS connection

Fault Code A3, B0, F1, FE1 and FE2

Listed below are the possible faults for the fault code A3, B0, F1, FE1 and FE2.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner blocked

Flue gas temperature sensor not properly positioned / Check Sensor

Fault Code A4

Listed below are the possible faults for the fault code A4.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Pump runs at maximum speed

Open circuit – BUS connection with variable speed heating circuit pump

Fault Code A7

Listed below are the possible faults for the fault code A7.

Boiler Model

System Behaviour

Diagnosis

Vitocrossal 300 / Vitodens 200-W / 222-F / 300

Control mode (stays in factory default setting)

Faulty Programming unit

Fault Code A8

Listed below are the possible faults for the fault code A8.

Boiler Model

System Behaviour

Diagnosis

Vitodens 222-F

Burner blocked. The venting program is started automatically

Air lock in the Internal circulation pump or minimum flow rate not achieved

Fault Code A9, BA, BB, BC and FE0

Listed below are the possible faults for the fault code A9, BA, BB, BC and FE0.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control Mode

Communication fault

Fault Code AD

Listed below are the possible faults for the fault code AD.

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 100 / Vitotronic 300-K with Vitotronic 300

Control mode

Isolation valve configuration fault: Coding OC:2, OC:3 or OC:4 set, and coding 4E:1 not set

Fault Code B1

Listed below are the possible faults for the fault code B1.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Communication fault, Programming unit

Fault Code B2

Listed below are the possible faults for the fault code B1.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Boiler cools down

Sensor inputs are not read correctly

Fault Code B3 and E5

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Setting via service level not possible

Data points are not stored; internal fault VR20

Fault Code B4

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 100 / 200 / 300 / Vitotronic 300-K with Vitotronic 100

Emissions test mode

Internal electronics fault

Vitocontrol-S with Vitotronic 100 / Vitodens 200-W

Regulates as if the outside temperature was 32°F (0°C)

Internal fault

Vitotronic 050/200-H

Undefined control characteristics

Internal electronics fault

Fault Code B5

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Internal electronics fault

Fault Code B6

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Constant mode

Invalid hardware recognised

Fault Code B9, ED, F0, FE5, FEC, FED, FEE, FEF, FFD and FFF

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Normal operation / fault around burner control unit

Internal fault

Fault Code C1

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control Mode

External safety equipment

Fault Code C2-C8, CD-CF, D2-D8, DA-DF, and E0

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Control mode

Open circuit – KM BUS to solar control unit / Extension AM1 / DE1-DE3 M1 / communication fault

Fault Code C9, CA and CB

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitotronic 100 / 300 / Vitotronic 300-K with Vitotronic 300

Boiler cools down

fault: Maximum pressure limiter 1 2

Fault Code CC and F0

Listed below are the possible faults for the fault code CC and F0.

Boiler Model

System Behaviour

Diagnosis

Vitodens 200

Burner control unit switches to lockout (due to large line voltage fluctuations)

Differential air pressure sensor / open circuit

Fault Code D4

Listed below are the possible faults for the fault code D4.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Boiler cools down

Fixed high limit has responded or fuse F2 has blown.

Fault Code D5

Listed below are the possible faults for the fault code D5.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Boiler drives up to electronic maximum limit

Boiler does not log in at the cascade control unit

Fault Code E1, E7, E8, E9, EA, EB, EC and FF2

Listed below are the possible faults for the fault code E1, E7, E8, E9, EA, EB, EC and FF2.

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner in fault mode

Ionisation current too high during calibration

Fault Code E2 and E3

Boiler Model

System Behaviour

Diagnosis

Vitodens 200-W / 222-F / Vitotronic 300

Burner in fault mode

Heating water flow rate too low during calibration; flow switch caused shutdown

Fault Code E4

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner blocked

Fault, supply voltage 24V

Fault Code EE and EF

Boiler Model

System Behaviour

Diagnosis

Vitocontrol-S with Vitotronic 100 / Vitocrossal 300 / Vitodens 200-W / 222-F / Vitotronic 300

Burner in fault mode

At burner start, flame signal is missing or too weak

     

Fault Code F5

Boiler Model

System Behaviour

Diagnosis

Vitodens 0-W / 200 / 0 / Vitotronic 300

Burner blocked

Faulty Air pressure switch

     

Fault Code F6, 58, F9, FE1, FE2 and FF6

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Gas pressure switch shows no gas pressure / Electrical connection fault

Gas shut-off valve closed; gas pressure switch faulty; multiple problems with gas supply

Fault Code FA and FB

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner in fault mode / Emergency operation

Fan not at standstill / plug-in connection

Fault Code FB7, FF4, FF2, FF7, FF8 and FF9

Boiler Model

System Behaviour

Diagnosis

Vitocrossal 200

Case A: Burner control unit in a fault state; system cools down; burner control unit locked out.

Case B: Type of coding card

Case A: Coding card not inserted in the burner control unit; incorrect or faulty coding card.

Case B: Coding card does not match burner control unit.

Fault Code FC

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner in fault mode

Gas valve faulty or faulty modulation valve control; or vent system blocked

Fault Code FE

Boiler Model

System Behaviour

Diagnosis

All Viessmann boilers

Burner blocked or in fault mode

Strong interference (EMC) field nearby, or Faulty main PCB

Fault Code FE4

Boiler Model

System Behaviour

Diagnosis

Vitocrossal 200

Burner shuts down

Multiple detection of undervoltage

Fault Code FFA, FFB and FR

Boiler Model

System Behaviour

Diagnosis

Vitocrossal 200 / 400-620 / 186-311

Fan runs without demand; Burner control unit in a fault state

Fan has not stopped; cable [100A] faulty; fan faulty; burner control unit faulty