BoilerFaultCodesYour boiler's fan, which safely clears exhaust gases from the unit, has stopped spinning correctly and prevented the 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: 325 Vdc supply fault, continuity issues in PCB to fan wiring, or Fan failure.
What causes this fault?
This fault occurs when the boiler's control board tries to start the fan but doesn't receive the correct signal that it is spinning at the right speed. The most common reasons are a build-up of debris causing the fan to seize or an electrical failure within the fan's motor or the main circuit board. Without the fan running correctly, the boiler cannot safely remove exhaust gases, so it shut downs for safety.
This fault is more common in winter, as the fan has to work much harder and for longer periods during cold spells, which can cause older motors to fail.
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 FAN LOCKOUT — no call-out fees, no surprises.
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