BoilerFaultCodesYour boiler’s internal flame sensor is dirty and can no longer see the fire, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Photocell filmed over (dirty)
What causes this fault?
This fault occurs when the photocell, which acts as the boiler's 'eye,' becomes coated in a thin layer of soot or oily film. Because the sensor can no longer detect the light from the flame, the boiler shuts down as a safety precaution to prevent unburnt fuel from building up. This is usually caused by natural wear over time or a slight change in the burner's combustion quality.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 75 — no call-out fees, no surprises.
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Worcester Bosch Greenstar Utility 18/25 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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