BoilerFaultCodesYour boiler has encountered an internal error and needs a simple restart to try and clear the fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: General fault; requires momentary interruption of the electrical supply to reset.
What causes this fault?
This fault occurs when the boiler's internal electronics detect a communication error or a safety interruption that prevents the system from starting. The most common reason is a temporary glitch in the control board or a sensor that has tripped due to minor overheating or a failed ignition attempt. It acts as a safety barrier to ensure the boiler does not operate until a qualified person or a manual reset has cleared the issue.
DIY fix possible
Locate the electrical spur switch or plug for the boilerTurn the power off for approximately 30 secondsTurn the power back on to see if the flashing light stops and the boiler restarts
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like Red light (flashing) — 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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