BoilerFaultCodesYour boiler's pilot light has gone out and will not stay lit, meaning the system cannot fire up 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: Failure of thermocouple, power unit or latching mechanism
What causes this fault?
This fault occurs when the boiler's safety system can no longer detect the small permanent flame used to light the main burner. The most common reason is that the heat-sensing probe has worn out over time or the internal magnetic switch within the gas valve has failed, causing the gas supply to shut off for safety. Without this pilot light being confirmed as active, the boiler is prevented from firing up entirely.
This issue is frequently noticed during the first cold spell of autumn when the boiler is worked harder after being mostly idle during the summer months.
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.
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A boiler cover plan would cover faults like B(5) — no call-out fees, no surprises.
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Potterton Flamingo RS40 RS50 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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