E17
''RETURN WATER
TEMPERATURE SENSOR
FAULT
''
Check whether return
water temperature sensor
is
mounted
and
sensor
works properly.
Replace
CH
return
water temperature
sensor.
Main board may be
broken.Replace main board.
YES
NO
E18
''TEMPERATURE
SENSORS
FAULT
''
Temperature change
on
temperature sensor is too much
(>30
°
C).
Check
whether
the
temperature sensor cables
are
working properly.
Replace the cables in
case of any problem.
Replace
CH
return water
temperature sensor.
YES
NO
Replace CH supply water
temperature sensor.
Replace main board.
NO
NO
30
