BoilerFaultCodesYour boiler has entered a safety lockout mode and has stopped running to protect its internal components.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Indicates a lockout condition; momentarily interrupt the electrical supply to reset.
What causes this fault?
This fault occurs when the boiler fails to detect a flame after several attempts, causing it to shut down for safety. The most common reasons include a worn-out ignition spark that can no longer light the gas, or a faulty gas valve that isn't letting fuel into the burner. In some cases, the internal control board may be failing to send the correct electrical signals to start the sequence.
DIY fix possible
Locate the boiler's electrical power switch (fused spur) on the wall nearby.Switch the power off for approximately 10 seconds.Switch the power back on and wait to see if the red light clears and the boiler fires up.
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 Red light flashes — no call-out fees, no surprises.
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Glow-worm Swift Flow 100 is discontinued — time for a new one?
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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