BoilerFaultCodesYour boiler is simply running a routine internal check as it starts up and there is no actual fault with the appliance.
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: Part of the self-test sequence sequence when switching on the appliance
What causes this fault?
This code appears because the boiler is performing a routine electronic check of its internal sensors and components at the moment it is switched on. It is a programmed safety sequence designed to ensure everything is working correctly before the burner fires up. It is not triggered by a mechanical failure or a broken part.
DIY fix possible
Wait for approximately 30 to 60 seconds for the code to disappear naturallyEnsure the power supply to the boiler remains switched on during this processIf the code stays on the screen for several minutes, try pressing the reset button once
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A boiler cover plan would cover faults like P5 — no call-out fees, no surprises.
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