BoilerFaultCodesYour boiler's internal pump has been left in a manual testing mode, meaning it isn't responding correctly to your heating demands.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump (SP) in manual mode.
What causes this fault?
This fault occurs when the boiler's internal pump has been manually set to a constant test speed, preventing it from automatically adjusting based on your heating needs. It is usually caused by an engineer accidentally leaving the pump in diagnostic mode after a service or a temporary software glitch in the control board.
DIY fix possible
Locate the central heating control dial on the front of the boiler.Turn the dial to the 'Reset' position and hold for three seconds.Release the dial and wait for the boiler to restart into its normal automatic operation mode.
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