BoilerFaultCodesYour boiler has stopped working because the internal fan, which safely exhausts fumes, isn't starting up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Check if there is 230V~ between motor connections on fan. If yes, replace fan. If no, isolate electrical supply test fan harness continuity; if satisfactory replace printed circuit board.
What causes this fault?
This fault occurs when the boiler's control system attempts to start the fan but detects no movement or electrical response. The most common reasons are a seized fan motor due to age-related wear or a failure on the main circuit board which prevents power from reaching the motor.
This issue is more frequent in autumn when boilers are turned back on after a summer of inactivity, as the fan motor can seize up during long periods of disuse.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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