Operating instructions

34
Fault code
on the dis-
play
System characteris-
tics
Cause Measures
51 No DHW heating Outlet temperature
sensor shorted out
Check the sensor (see
page 43).
52 Burner blocked Short circuit, flow
sensor
Check connections and
lead; replace sensor if
required.
58 No DHW heating Cylinder tempera-
ture sensor lead
broken
Check the sensor (see
page 40).
59 No DHW heating Outlet temperature
sensor lead broken
Check the sensor (see
page 43).
5A Burner blocked Break, flow sensor Check connections and
lead; replace sensor if
required.
A9 Regulated operation
without Open Therm
device
Communication
fault Open Therm
device
Check connections and
lead; replace Open Therm
device if required.
b0 Burner blocked Short circuit, flue
gas temperature
sensor
Check the sensor (see
page 44).
b8 Burner blocked Break, flue gas
temperature sen-
sor
Check the sensor (see
page 44).
E5 Burner blocked Internal fault Check the ionisation elec-
trode and cables.
Press "Reset" (see
page 36).
F0 Burner blocked. Internal fault Replace the control unit.
F1 Burner in a fault
state
Max. flue gas tem-
perature exceeded
Check the heating system
fill level. Check the circu-
lation pump. Vent the sys-
tem.
Press "Reset" (see
page 36).
Troubleshooting
Fault messages on the display
(cont.)
5366 836 GB