BoilerFaultCodesTechnical description
No flame signal with low output
What causes this fault?
This fault occurs when the boiler's internal sensor can no longer detect a steady flame while the unit is operating at its quietest, most efficient setting. The most common reason is that the sensing probe has become dirty or worn out, though it can also be caused by the gas valve failing to deliver a consistent flow of fuel at low pressures.
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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