BoilerFaultCodesYour boiler has detected an internal communication or unexpected component fault and has stopped working 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: Miscellaneous error.
What causes this fault?
This fault occurs when the boiler's internal computer is unable to communicate with its electrical components or receives an unexpected signal that doesn't match normal operation. It is often caused by a malfunctioning main circuit board or a loose connection in the internal wiring harness that prevents instructions from being sent correctly. In some cases, a failing gas valve can also trigger this 'miscellaneous' error by sending unrecognised feedback to the control system.
DIY fix possible
Turn the selector switch to the 'Reset' position and hold for 5 seconds.Release the switch and wait for the boiler to attempt to restart.Ensure your gas supply is active and your credit meter (if applicable) has funds.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 6 red flashes — 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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