BoilerFaultCodesYour boiler has lost track of the basic flame sensor settings required to run safely and needs to be restarted to recalibrate itself.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical 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.
DIY fix possible
Locate the power or reset button on the front control panelPress and hold the reset button for 5 secondsWait for the boiler to complete its restart sequence to see if the error clears
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A boiler cover plan would cover faults like E1-68 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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