BoilerFaultCodesIdeal P1 Fault Code
The Ideal P1 fault code means: your boiler is displaying a service setting notification to run the pump at maximum speed, which usually indicates an installation or maintenance mode rather than a dangerous mechanical failure.. It appears on 5 Ideal models in our database.
Technical description: To set the minimum CH pump speed to 100%
What causes the Ideal P1 fault?
This code appears when the boiler has been manually adjusted to run its internal pump at maximum speed, typically during the initial setup or a system cleanse. It essentially means the energy-saving variable speed feature has been overridden to help flush air or debris out of the system. While not a mechanical breakdown, the boiler will stay in this high-performance mode until the setting is changed back to automatic.
DIY fix possible
Press the 'Mode' button to return the boiler to its normal operating screen.Turn the mains power to the boiler off and back on again to reset the display.If the code persists, check if the installer left the boiler in service mode.
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Gas Safe Register →Ideal models that show the P1 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal P1 fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026