BoilerFaultCodesYour boiler has entered a safety lockout mode and stopped working because it has detected a recurring mechanical or ignition internal fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: FLASHING. Boiler at lock-out
What causes this fault?
This fault occurs when the boiler's internal computer detects a major failure that prevents it from firing up safely, such as a lack of spark or a failure to detect a flame. The most common reasons are worn-out ignition parts that can no longer create a spark or a faulty control board that is unable to process safety signals correctly.
DIY fix possible
Locate the reset button on the control panelPress and hold the reset button for several secondsWait for the boiler to attempt to reignite; if it fails again, call a Gas Safe engineer
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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