BoilerFaultCodesTechnical description
Condition for fan operation on the PCB.
What causes this fault?
This fault occurs when the boiler's control board sends a signal for the fan to start, but it fails to detect the correct electrical response to confirm it is spinning safely. The most common reason is an internal electronic failure on the main circuit board or a mechanical breakdown within the fan motor itself. Without the fan running to clear exhaust gases, the boiler will stay in a safe shutdown mode.
This fault is slightly more common in winter when the fan has to work harder and run for longer periods to meet higher heating demands.
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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