BoilerFaultCodesTechnical description
Fan speed deviation
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is spinning too slowly or not at all, preventing the safe movement of air. The most common reasons include a buildup of dust and debris inside the fan motor, a loose electrical connection, or a component failure on the main control board. Without the fan functioning at the precise speed required, the boiler cannot safely ignite or exhaust waste gases.
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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