56
5784 568 - 03
Vitodens 100-W, B1HA series & B1KA Combi Installation/Service
Diagnosis
(continued)
Diagnostics table: Faults with fault display on control unit
Fault code in
display window
System
characteristics
*
1
Cause
Corrective measures
0A
Burner blocked
CO limiter (if installed) has
responded. CO concentration
too high.
Check the heating system. Remove
the cause of escaping CO.
Gas pressure switch (if installed)
has responded.
Gas pressure too low.
Check the gas supply.
0b
Burner blocked
Low water, pump or flow switch
defective
Check water pressure, circulation pump,
flow switch
0C
Burner blocked
Mains voltage too low
Check the power supply.
10
Constant mode
Outdoor temperature sensor
shorted out
Check the optional outdoor temperature
sensor and wiring (see page 59).
18
Constant mode
Outdoor temperature sensor
wire broken
Check the outdoor temperature sensor and
wiring (see page 59).
30
Burner blocked
Boiler water temperature sensor
shorted out
Check the boiler water temperature sensor
(see page 58).
38
Burner blocked
Boiler water temperature sensor
wire broken
Check the boiler water temperature sensor
(see page 58).
50
No DHW heating
Tank temperature sensor
shorted out
Check sensor
(see page 62)
51
No DHW heating
Outlet temperature sensor
shorted out
Check sensor
(see page 62).
52
Burner blocked
Flow sensor shorted out
Check connections and wire;
replace sensor if required.
58
No DHW heating
Tank temperature sensor
wire broken
Check sensor. (see page 62)
59
No DHW heating
Outlet temperature sensor wire
broken
Check the sensor (see page 62).
5a
Burner blocked
Flow sensor wire broken
Check connections and wire; replace sensor
if required.
aA3
Burner blocked
Flue gas temperature sensor
incorrectly positioned.
Position flue gas temperature sensor
correctly.
a9
Regulated operation
without OpenTherm
device
Communication fault
OpenTherm device
Check connections and wire; replace
OpenTherm device if required.
b0
Burner blocked
Flue gas temperature sensor
shorted out
Check sensor
(see page 61).
b7
Emergency mode
Burner control unit fault
Reset boiler control
b8
Burner blocked
Flue gas temperature sensor
wire broken
Check sensor
(see page 61)
Troubleshooting
