BoilerFaultCodesYour boiler's pilot light is likely going out because a safety sensor has lost its connection, preventing the unit from staying lit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Loose thermocouple connection into control valve
What causes this fault?
This fault occurs when the safety sensor that detects the pilot light fails to send a clear signal back to the main gas valve. The most common reason is that the physical connection between the thermocouple and the control box has vibrated loose or become corroded over time. Because the boiler can no longer verify that a flame is present, it shuts off the gas supply as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like B(2) — 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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