BoilerFaultCodesYour boiler is in preheat mode, which is a normal setting that keeps a small amount of water warm so it reaches your taps faster.
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: Domestic hot water preheat
What causes this fault?
This code appears when the preheat function is active, which periodically fire the boiler to warm the internal heat exchanger. It is not a fault, but rather a status indicator showing the boiler is maintaining a small reservoir of hot water to reduce waiting times at the tap. If you see this frequently, it simply means the boiler is keeping itself ready for your next shower or hand wash.
DIY fix possible
Locate the DHW preheat knob or button on the control panel.Turn the knob to the 'off' position if you wish to disable this feature and save energy.Observe the display to see if the 'P' disappears, indicating the mode is deactivated.
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