BoilerFaultCodesYour boiler appears to have no power and the display is completely dead, meaning it cannot provide any heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Permanent mains supply to boiler; Boiler mains switch on; Fuse F1; Transformer (both coils below 100Ω); Otherwise replace control board (if boiler does not operate correctly).
What causes this fault?
This fault occurs when the electrical circuit inside the boiler is interrupted, preventing power from reaching the internal components. The most common reason is a blown internal fuse or a failure within the transformer, which acts as the heart of the boiler's electrical system. In some cases, a power surge or a short circuit on the main control board can cause the unit to shut down completely to prevent further damage.
DIY fix possible
Check if the main electricity switch for the boiler is turned onCheck your home's consumer unit (fuse box) to see if a circuit breaker has trippedReplace the fuse in the external boiler spur switch with a new 3-amp fuse
Find a Gas Safe engineer
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Worcester Bosch Greenstar 12Ri 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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