BoilerFaultCodesYour boiler's small starter flame has become blocked by dust or debris, preventing the main heating system from firing up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: BLOCKED PILOT
What causes this fault?
This fault occurs when the tiny opening that fuels the starter flame becomes clogged with household dust, lint, or carbon build-up. Without a steady pilot flame to heat the internal safety sensor, the boiler will refuse to light the main burner as a security precaution. The most common reason is simply a lack of regular servicing, allowing debris to accumulate over time until the gas flow is restricted.
This issue often surfaces in autumn when the boiler is switched back on after being idle during the summer months, allowing dust to settle and harden in the pilot assembly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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