BoilerFaultCodesWhat the manual says
Manufacturer manualOccurs once per second. Can only be cleared by using the facia reset button (press for at least one second).
What causes this fault?
This fault occurs when the boiler fails to detect a stable flame after several attempts to light. The most common reasons include a lack of gas supply, worn-out ignition parts that can no longer create a spark, or a sensor that is too dirty to 'see' the flame even when it is present.
This fault is more common in winter, as severe cold can cause external gas regulators to freeze or pipes to become blocked, disrupting the fuel flow required for ignition.
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.
Avoid the next call-out bill
A cover plan would handle faults like Slow flash: no call-out fees, no surprise bills.
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