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 status code appears when you turn on a hot tap and the boiler begins its startup sequence to heat your water. It occurs as the internal fan begins to spin up to the correct speed to safely vent exhaust gases, which is a vital part of the ignition process. This is not a fault, but rather a brief progress update showing that the boiler is responding correctly to your request for hot water.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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