BoilerFaultCodesYour boiler is stuck in a service mode where it runs at maximum power constantly, which is usually triggered during maintenance or testing.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: The display shows alternatively the CH flow temperature and P2. The appliance works continuously at the maximum power (see service function 2.F).
What causes this fault?
This code appears when the boiler has been manually put into a high-power testing mode, usually by a heating engineer during a service. It happens when the internal settings are adjusted to force the burner to run at maximum output to check emissions or performance. Because this is a manual override, the boiler will not return to normal heating routines until the service setting is deactivated.
DIY fix possible
Press and hold the 'Reset' button for about 5 seconds to exit service modeSwitch the boiler off at the main electrical fused spur, leave it for 30 seconds, and switch it back onCheck that the 'Service' button has not been accidentally pressed or left on by a visiting engineer
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