BoilerFaultCodesYour boiler has shut down completely for safety reasons because it has detected a serious internal error that requires a professional inspection.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Safety lockout
What causes this fault?
This fault occurs when the boiler's internal computer detects a critical failure in the electrical signals that manage the ignition and combustion process. It physically triggers a total shutdown because the unit can no longer verify that it is burning gas safely. The most common reasons are a malfunctioning main control board or a failure in the hardware that controls the gas flow.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 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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