8
Fault
Possible cause
Remedy
tion phase is acceptable)
•
Pump switches on after
prolonged standstill without
any noticeable cause
•
Legionella protection
feature has become
activated, or self-
calibration feature has
tripped
•
System operates properly
- no changes required
•
Pump does not start although
hot water is withdrawn from
system
•
There is already hot water
in the circuit
•
Water in hot-water
storage tank is not or only
slightly heated
•
Controller operates
properly. In this situation,
no cause for starting the
pump exists
•
Pump switches on only after
greater quantities have been
withdrawn or does not switch
on at all
•
Pump switches on frequently
without any noticeable cause
•
Flow sensor not properly
attached on flow pipe
•
Insufficient heat contact
between flow sensor and
pipe
•
Draught on sensor
•
Sensor has not been fitted
to pipe but to large fittings
which heat up only slowly
•
Sensor located too far
away from hot-water
•
Properly and very
carefully position and
fasten flow sensor (see
installation instructions)
•
Provide sensor together
with pipe with heat
insulation
•
Select small wall
diameters for fastening
