Fault Messages - Viessmann B1KE Combi Series Installation And Service Instructions Manual

Troubleshooting

Fault Messages

Displayed System characteristics
fault code
F.5 System continues op-
erating in normal mode
with replacement value.
F.7 No DHW heating
F.8 No DHW heating
F.13 Regulates as if the out-
side temperature were
32°F (0°C).
F.14 Regulates as if the out-
side temperature were
32°F (0°C).
F.49 Burner in a fault state
F.50 Burner in a fault state
F.59 Burner locked out
72
Vitodens 100-W, B1HE/B1KE Combi Installation/Service
Note: For diagnostics and troubleshooting, see chapter
Cause Measures
Lead break or short Check plug 33/X6 and cable:
circuit

pin 1 and 2.

off and back on again.
Lead break, storage

tank temperature
sensor


Short circuit, storage Check storage tank temperature sensor (plug 5, wires
tank temperature 3 and 4).
sensor Replace faulty component if necessary.
Lead break, outside

temperature sensor


Replace faulty component if necessary.
Short circuit, out- Check outside temperature sensor and connection to
side temperature sensor (external plug, and contacts 1 and 2).
sensor Replace faulty components if necessary.
Flue gas temperature Check flue gas temperature sensor.
sensor disconnection Reset the boiler.
Short circuit, flue gas Check flue gas temperature sensor.
temperature sensor Reset the boiler.
Power supply, low Check mains voltage.
voltage If voltage is correct and the fault occurs repeatedly,
replace the fan unit.
"Repairs".
Fault messages dependent on boiler equipment
level
Check voltage level, to see if 5V present at plug 33,
Turn the gas condensing system boiler ON/OFF switch
Check DHW setting in the commissioning
assistant and correct if necessary.
Check storage tank temperature sensor (plug 5,
wires 3 and 4).
Measure voltage at sensor input on electronics
module. Target value: 3.3V– with sensor disconnected.
Replace faulty component if necessary.
Check the operating mode setting in the
commissioning assistant and correct if necessary.
Check outside temperature sensor and connection to
sensor (external plug, contacts 1 and 2).
Measure voltage at sensor input on electronics module.
Target value: 3.3V– with sensor disconnected.