BoilerFaultCodesPotterton P1.0-2.9 Fault Code
Also written as P1029 — same fault.
The Potterton P1.0-2.9 fault code means: your boiler is operating normally and showing that the system pressure is at a healthy level while the water is warm.. It appears on 1 Potterton model in our database.
Technical description: Normal pressure, system warm/hot. O.K.
What causes the Potterton P1.0-2.9 fault?
This is not a fault, but rather a status reading showing the current water pressure within your central heating system. The numbers indicate that the internal pump is active and the water has expanded slightly as it heats up, which is exactly how the system is designed to function. As long as the display remains in this range while the heating is on, your boiler is operating perfectly.
You may notice these readings more frequently during winter when the heating is running constantly and the system water remains hot.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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Gas Safe Register →Potterton models that show the P1.0-2.9 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Potterton P1.0-2.9 fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026