BoilerFaultCodesYour boiler is having trouble managing its flame correctly and has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Digitised ionisation potential error
What causes this fault?
This fault occurs when the boiler's internal computer is unable to correctly measure or verify the electrical signal sent back by the flame. It usually happens because the sensing electrode has become worn or carbon-coated, or because the gas valve is not delivering the precise mixture needed to sustain a steady burner signal. Without this confirmation that the flame is safe and stable, the boiler enters a safety shutdown.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like D.44 — 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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