3
Failures / Errors
GB012 - 25K
14
4Y
is flashing.
Central heating flow temperature sensor failure (pump is running).
Control Step
Action
1.
Check if CH flow temperature sensor
(NTC) is damaged or not ?
B
Switch off the appliance.
B
Pull cables out.
B
Measure the electrical resistance
of the NTC sensor.
Are the measured values OK ?
(resistance table)
yes:
B
Check the connection terminal on NTC.
4Y failure still exist ? -->2.
no:
B
Change NTC.
B
Connect the cable.
B
Switch on the appliance.
4Y failure still exist ? -->2.
2.
Check if the cables are damaged or
not?.
B
Switch off the appliance.
B
·If NTC changed :
- disassemble the NTC cable from
NTC.
- measure the sensor resistance.
- assemble the NTC to NTC cable
again.
B
Pull out the 20 poled (main socket)
connector from the electronic
card.
B
Measure the electrical resistance
of NTC on socket. Are the meas-
ured resistance values at at NTC
and socket connection same?
yes:
B
Chance the cable harness.
B
Switch on the appliance.
4Y failure still exist ? -->3.
no:
-->3.
3.
Electronic card is defect.
B
Switch off the appliance.
B
Cut mains supply.
B
Change the electronic card.
B
Connect to main supply.
B
Switch on the appliance.
