A7 and fault indicator LED are flashing.
(Boiler still produces hot water but at a lesser degree of accuracy over the temperature.)

Water NTC sensor defective.

StepCheck Action
1.▶ Check if the water NTC connector corroded, damaged or dirty.yes:▶ Change relative parts. A7? go to step 2
no:go to step 2
2.▶ Switch OFF the appliance.
▶ Disconnect the boiler power
connection.
▶ Un-plug 20-pin connector from PCB.
▶ Check resistance from
connections 3 to 4 on the cable side. Does the value match the ones described in table 39, page 36?
yes:▶ Connect the boiler electrical connection.
▶ Switch ON the appliance.
▶ Make a note of the altered service function
settings (see table 4 on page 6) in order to keep the altered values.
▶ Switch OFF the appliance.
▶ Disconnect the boiler power connection.
▶ Change PCB control board.
▶ Reconnect the appliance power connection.
▶ Switch ON the appliance.
▶ Restore service settings previously noted.
no:go to step 3
3.▶ Un-plug NTC sensor from cable.
▶ Check resistance of NTC sensor. Does the
value match the ones described in table 39, page 36?
yes:▶ Change the 20-pin connector lead assembly.
▶ Reconnect the boiler electrical connection.
▶ Switch ON the appliance.
no:▶ Change NTC sensor.
▶ Reconnect the boiler electrical connection.
▶ Switch ON the appliance.

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