BoilerFaultCodesTechnical description
Replace printed circuit board.
What causes this fault?
This fault occurs when the boiler's control centre is no longer able to send a consistent voltage to the fan, causing it to speed up and slow down erratically. The most common reason is that the electrical components on the main circuit board have aged and degraded, losing their ability to regulate the startup sequence correctly.
This issue often becomes apparent during the first cold spell of autumn, when the circuit board is suddenly tasked with constant operation after being idle over the summer.
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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