BoilerFaultCodesIdeal F01 Fault Code
The Ideal F01 fault code means: your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.. It appears on 1 Ideal model in our database.
Technical description: Low Water Pressure
What causes the Ideal F01 fault?
This fault occurs when the water pressure inside your heating system drops below a safe operating level, causing the boiler to shut down to prevent damage. The most common reasons for this are a leak somewhere in your radiator network or the pressure naturally dropping over time, especially after you have bled your radiators.
This fault is more common in autumn and winter when homeowners turn their heating back on after a long break and notice leaks from valves or joints.
DIY fix possible
Locate the external filling loop, which is a silver braided hose connected to your boiler pipes.Open the small tap or valve on the filling loop to allow water to enter the system.Watch the pressure gauge on the front of the boiler until the needle reaches the green zone (typically 1.0 to 1.5 bar).Close the tap firmly to stop the flow of water.
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Ideal models that show the F01 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal F01 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 7 July 2026