BoilerFaultCodesWhat the manual says
Manufacturer manualDHW mode: Fan start-up. The fan start-up for domestic hot water mode is activated.
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This code appears when you turn on a hot tap and the boiler begins its safety checks before igniting the burner. It happens because the control board is verifying that the fan is spinning at the correct speed to safely expel exhaust gases. As long as the code disappears and hot water follows, it indicates the boiler is functioning exactly as it should.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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