Viessmann B1KE Combi Series Installation And Service Instructions Manual page 70

Troubleshooting
Fault Display on the Programming Unit
Further messages
Service messages
Message on the display
P.1
P.4
P.8
Status messages
Message on the display
S.60
S.74
S.75
S154-1
Warning messages
Messages on the display
A.12
A.18
A.19
A.20
Information
Messages on the display
I.56
I.57
I.59
70
(continued)
Meaning
Interval until the next service.
Top up heating water.
Service due after burner hours run.
Meaning
Summer mode active (outside temperature economy function)
Heating suppression, heating
DHW recirculation pump active
Boiler internal flowswitch is in the open position
Meaning
Real time clock battery flat.
Possible condensate backup in the
heat cell
Temperature limiter has responded
Service interval could not be activated.
Meaning
External demand active
External blocking active
Parameters were restored (parameter set was flashed to BCU electronics module).
Vitodens 100-W, B1HE/B1KE Combi Installation/Service
Measure
Replace the battery (type CR2032) in
the HMU heat management unit.
Check combustion chamber and
condensate drain.
Condensate may escape when removing
the burner door. Take appropriate
precautions to protect the electronic
components.
If condensate is backed up into the
combustion chamber, replace the
insulating ring, insulating block, flame
body, insulating mats and ionization
electrode. If the condensate has reached
the flame body assembly, also replace
the gasket of the flame body assembly.
Check the time and date settings.