BoilerFaultCodesYour boiler is simply showing that it is going through its normal starting process and trying to fire up.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Boiler indicates start-up sequence
What causes this fault?
This occurs when the boiler's internal control board begins the ignition sequence to provide heating or hot water. It isn't a failure, but rather a status update showing that the fan is spinning and the electrodes are preparing to spark. You will typically see this for a few seconds every time the boiler starts a new cycle.
DIY fix possible
Wait for the boiler to complete its start-up sequenceCheck that your thermostat is calling for heatEnsure the gas supply is turned on if the code persists
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A boiler cover plan would cover faults like P3 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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