BoilerFaultCodesYour boiler has detected an electrical supply issue, likely caused by a tripped switch, a blown fuse, or a temporary power failure.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Correct power supply problem.
What causes this fault?
This fault occurs when the boiler's control system detects an interruption or an irregularity in the electrical current reaching the unit. It is most commonly caused by a blown 3-amp fuse in the external spur switch or a failure within the boiler's internal circuit board which prevents it from processing power correctly.
DIY fix possible
Check your home's main fuse box (consumer unit) to see if any circuit breakers have tripped.Inspect the fused spur switch near the boiler and replace the 3-amp fuse if it has blown.Turn the boiler power switch off and back on to attempt a reset of the internal electronics.
Find a Gas Safe engineer
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