Troubleshooting
Operating and installation instructions 0020248967_00
37
8
8.2 Fault
messages
If a fault occurs, a fault code
Fx
. is shown
in the display instead of the temperature
display.
Fault
Possible
cause
Remedy
F1
Valve drive
stiff
Check whether the
tappet for the heat-
ing valve is jammed.
F2
Setting range
too big
Check the fastening
for the radiator
thermostat.
F3
Setting range
too small
Check whether the
tappet for the heat-
ing valve is jammed.
Battery volt-
age low
Replace the unit’s
batteries; see sec-
tion “Changing the
batteries”.
