BoilerFaultCodesYour boiler has lost power or has a serious internal electronic failure, meaning it cannot start the ignition process to provide 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: No green light (Red lights function)
What causes this fault?
This fault occurs when the boiler's control system loses its vital electrical feed, preventing it from managing the heating process. The most common reason is a blown internal fuse or a failure within the Printed Circuit Board (PCB) which acts as the boiler's brain. In some cases, a faulty transformer is unable to convert power correctly, leading to a total loss of the green operation light.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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 FAIL POINT B — no call-out fees, no surprises.
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Worcester Bosch 24/28CDi II RSF 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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