BoilerFaultCodesTechnical description
PILOT WILL NOT LIGHT
What causes this fault?
This fault occurs when the boiler's small pilot flame fails to stay lit, which is necessary to safely ignite the main heating burners. The most common reasons are a buildup of soot blocking the tiny gas nozzle or a worn-out sensor that can no longer detect the heat from the flame.
This issue often surfaces in autumn when the boiler is switched back on after being idle all summer, as dust or debris can settle in the pilot assembly during the warmer months.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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