BoilerFaultCodesWhat the manual says
Manufacturer manualInterruption: Flow sensor - Flow temperature sensor defective or not connected
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This fault occurs when the boiler's control board can no longer detect a signal from the sensor that monitors the temperature of the water leaving the unit. The most common cause is a failure of the internal thermistor itself, though it can also be triggered by loose or corroded electrical connections within the boiler's internal wiring.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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