Operating instructions

37
Fault finding
6 720 610 598 GB (03.11) TD
5Fault finding
Problem Cause Remedy
Desired room
temperature is not
reached
Thermostatic
valve(s) set too
low
Increase thermo-
static valve set-
ting(s)
Temperature con-
trol for CH flow
set too low
Increase CH flow
temperature con-
trol setting
Air trapped in
heating system
Bleed radiators
and heating sys-
tem
Desired room
temperature
exceeded by large
amount
Radiators are too
hot
Turn down ther-
mostatic valves
Temperature rises
instead
of falling
Clock is incor-
rectly set
Check setting
Room tempera-
ture too high in
Economy mode
Building retains
heat well
Start Economy
mode sooner
No display or dis-
play unit does not
respond
Momentary power
failure
Switch off appli-
ance at master
switch, wait a few
seconds and
switch on again
Storage Tank
doesn’t warm up
Temperature con-
trol is too low
Turn the tempera-
ture control to the
desired tempera-
ture