Boiler fault codes

Viessmann boiler faults: fault codes, causes and parts (page 2 of 2)

Codes 151 to 285 of the 285 fault codes for Viessmann. Looking for a specific code? Use the search on the first page.

Viessmann boiler fault codes 151 to 285 of 285

The code list is split over 2 pages. Looking for a specific code? Use the search on the first page: it searches all 285 codes in one go.

Code	Cause
95	CO limit value exceeded
95	OpenTherm remote control not connected
96	CO monitor sensor error
98	Open circuit of temperature sensor /
99	Open circuit of temperature sensor aÖ
9A	Open circuit of collector temperature sensor
9B	Open circuit of collector return temperature sensor
9C	Open circuit of cylinder temperature sensor
9E	Too little or no flow in the solar circuit or tem- perature monitor has been activated.
9F	Solar control module or Vitosolic error
A	Dynamic gas pressure too low, gas pressure monitor switches system off
A2	System pressure too low
A3	Flue gas temperature sensor not positioned correctly
A4	Max. system pressure exceeded
A7	Control section defective
A8	Air in the internal circulation pump or minimum flow rate not reached
A9	Internal circulation pump blocked
A9	OpenTherm appliance communication error
B0	Short circuit of flue gas temperature sensor
B1	Control unit communication error
B5	Internal fault
B7	Boiler coding plug error
B8	Open circuit of flue gas temperature sensor
BA	Communication error with expansion kit for heating circuit 2 (with mixing valve)
BB	Communication error with expansion kit for heating circuit 3 (with mixing valve)
BC	Communication error with Vitotrol remote control, heating circuit 1 (without mixing valve)
BD	Communication error with Vitotrol remote control, heating circuit 2 (with mixing valve)
BE	Communication error with Vitotrol remote control, heating circuit 3 (with mixing valve)
BF	Incorrect LON communication module
C1	Communication error with EA1 expansion
C2	Communication error with solar control module or Vitosolic
C3	Communication error with AM1 expansion
C4	Communication error with Open Therm expansion
C5	Communication error with speed-controlled internal pump
C6	Communication error with speed-controlled external heating pump, heating circuit 2 (with mixing valve).
C7	Communication error with speed-controlled external heating pump, heating circuit 1 (without mixing valve).
C8	Communication error with speed-controlled external heating pump, heating circuit 3 (with mixing valve).
CD	communication error
CF	Communication error with communication module
D3	Communication error with fan unit
D4	Air mass flow in fan unit not detected.
D5	Fan blocked
D6	Input DE1 on EA1 expansion reports a fault.
D7	Input DE2 on EA1 expansion reports a fault.
D8	Input DE3 on EA1 expansion reports a fault.
DA	Short circuit in room temperature sensor, heating circuit 1 (without mixing valve)
DB	Short circuit in room temperature sensor, heating circuit 2 (with mixing valve)
DC	Short circuit in room temperature sensor, heating circuit 3 (with mixing valve)
DD	Open circuit in room temperature sensor, heating circuit 1 (without mixing valve)
DE	Open circuit in room temperature sensor, heating circuit 2 (with mixing valve)
DF	Open circuit in room temperature sensor, heating circuit 3 (with mixing valve)
E0	Fault in external LON nodes
E1	Ionisation current too high during calibration
E2	No calibration due to insufficient flow rate
E3	Heat draw-off too low during calibration. Temperature monitor has been switched off.
E3	Fault in the safety circuit
E4	24 V supply voltage fault
E5	Flame amplifier fault
E5	Internal fault
E6	System pressure too low
E7	Ionisation current too low during calibration
E8	Ionisation current not in the valid range
E9	Repeated flame loss during calibration
EA	Ionisation current too low during calibration. Difference from the previous value not plausible.
EB	Process fault, shutdown during calibration.
EC	Parameter error during calibration
EE	Flame signal is not present or too low at burner start.
EF	Flame loss immediately after flame formation (during the safety time).
Ed	Internal fault in the control unit
F	See fault code
F 04	Burner control unit has been reset more than 5 times in the last 15 min
F 11	Undervoltage detection
F 12	Power failure, loss of voltage detected
F 13	Safety circuit not de-energised
F 16	EMC fault
F 40	Incorrect setting of fan setpoint in parameter set
F 41	Fan defective, cable "100A" defective or open circuit, fan not suitable for the required speed
F 42	Fan defective, external power supply to the fan not connected or defective, cable "100A" defective or open circuit, fan blocked (possibly by foreign object)
F 43	Internal fault in the burner control unit and during test of the ionisation input
F 4F	Stick does not match the burner control unit
F 4b	Parameter set activated but stick not inserted in burner control unit; stick defective
F 4c	Parameters could not be transferred from the stick
F 4d	Password entered for the stick is not valid
F 50	Internal fault in the actuator feedback signal, output relay does not switch
F 53 (9)	Gas valve does not open, gas valve leaks
F 54	EEPROM of the stick changed or erased; stick defective
F 55	Stick defective
F A0 and F A1	Internal fault, fan cannot reach the setpoint
F A2	Open circuit, safety circuit was opened (jumper plug fJ)
F A3	Values in the burner control unit and the parameter memory stick differ; time-out because the password was not entered
F A4 and F A5	Internal fault in the feedback signal of the gas safety valves, output relay does not switch
F A6	Gas multiblock leaks; gas escapes and burns
F A7	Ionisation electrode incorrectly set, plug of the ionisation cable not connected Ignition electrodes incorrectly set Insulation sheath of the ignition electrodes cracked Incorrect gas type set Combination gas valve does not open Connections "L 1" and "N" of the mains connection of the controller or of the burner control unit swapped Combustion values not optimal
F A8	Incorrect gas type set Flame cup faulty Wrong parameter memory stick inserted Combustion values not optimal
F A9	Incorrect gas type Flame cup faulty Wrong parameter memory stick inserted Combustion values not optimal
F AA	Wind influence on fan
F AA	Air pressure switch defective
F AE	Valve 1 leaks
F AF	Valve 2 leaks
F Ab	Air pressure switch defective, incorrectly connected or incorrectly set
F Ab	Flue gas blockage, condensate blockage
F Ab	Fan defective, cables defective or open circuit
F Ad	Gas valve closed, gas pressure switch defective
F0	Internal fault
F1	Flue gas temperature limiter has been activated.
F1	Maximum flue gas temperature exceeded
F1 (flashing)	Parameter memory stick not inserted correctly or defective
F2	Temperature limiter has been activated
F2	Temperature limiter has been activated.
F2 (flashing)	Connected indication is invalid
F3	Flame signal already present at burner start.
F3	Flame signal already present at burner start
F4	No flame signal.
F7	Short circuit or open circuit in water pressure sensor.
F8	Fuel valve or modulation valve does not close.
F8	Fuel valve closes with a delay.
F8	Fuel valve closes too late
F9	Fan speed too low at burner start
F9	Fan speed too low
FA	Standstill or required fan speed not reached
FA	Fan standstill not reached
FB	Flame loss in the stabilisation or operating phase
FC	Gas multiblock defective or incorrect control of modulation valve or flue gas path blocked
FC	Electrical control of fan (control unit) defective
FE	EEPROM error on PCB
FE	Boiler coding plug missing.
FF	Internal fault or reset button R is blocked
FF	Automatic burner control fault
FF	Burner control unit fault
Fd	Burner control unit fault
Fd	Automatic burner control fault
b0	Short circuit of flue gas temperature sensor
b7	Burner control unit fault
b8	Open circuit of flue gas temperature sensor
c00	Data from the new parameter memory stick transferred by password

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