BoilerFaultCodesYour boiler has no power reaching it, which means it cannot operate and the display panel will remain completely blank.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No power at control board
What causes this fault?
This fault occurs when the electrical supply to the boiler is interrupted, either from an external source or a failure within the boiler's internal circuitry. The most common reason is a blown fuse at the wall spur or a failed component on the main control board that has caused a short circuit.
This issue is slightly more frequent during the autumn and winter months when power surges caused by electrical storms or grid instability are more prevalent.
DIY fix possible
Check if your home's main electrical consumer unit has a tripped circuit breakerEnsure the boiler's fused spur switch (usually located near the boiler) is turned onReplace the 3-amp fuse in the boiler's external fused spur switch
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 Blue light: Off, Lockout reset: Off — 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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