BoilerFaultCodesTechnical description
Ion base value is outside the factory limits or saved incorrectly – try resetting the boiler
What causes this fault?
This fault occurs when the boiler's internal computer loses the reference point for the flame signal, meaning it can no longer accurately monitor if the gas is burning safely. The most common reason is a build-up of carbon or wear on the sensor probe, but it can also be caused by a software glitch or an inconsistent signal from the main control board.
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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