BoilerFaultCodes 0b
Flow of water too low, air in heat exchanger, or flow switch faulty
Viessmann Vitodens 100 Compact Fault codes & diagnostics
19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Gas Discontinued
GC Number 41-819-10
Download the Viessmann Vitodens 100 Compact manual
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The fault code is already on your display
Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →
Severity at a glance
Each cell = one fault code. Hover to identify. 19 Unrated
Just want the most common Viessmann Vitodens 100 Compact faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes
All 19 documented codes
Tap any card for details
30
Boiler temperature sensor shorted out
38
Boiler temperature sensor lead break
60
Return temperature sensor shorted out
68
Return temperature sensor lead break
b1
Communication fault – programming unit (internal)
b5
Internal fault
E4
Fault – supply voltage
E5
Internal fault
F0
Internal fault
F2
Temperature limiter has responded
F3
The flame signal is already present at burner start
F4
No flame signal is present
F5
Air pressure switch faulty / Sticking mixture damper
F8
Fuel valve closes too late
F9
Fan speed too low at burner start
FA
Fan not at standstill
Fd
Burner control unit fault
FE
Faulty main PCB