BoilerFaultCodesYour boiler has stopped working because its internal fan is unable to communicate with the main control board, preventing the boiler from safely clearing waste gases.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan problem – tachometer signal interrupted for 1 hour or longer – check the wiring and the fan
What causes this fault?
This fault occurs when the boiler's computer loses track of how fast the internal fan is spinning, which is a vital safety check. It is usually caused by a mechanical failure within the fan motor or a loose electrical connection that prevents signals from reaching the main control board. Without this confirmation, the boiler shuts down to ensure that dangerous exhaust gases are not trapped inside the unit.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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