BoilerFaultCodesIdeal F01 Fault Code
The Ideal F01 fault code means: your boiler has lost water pressure, which prevents it from firing up to provide heating or hot water.. It appears on 3 Ideal models in our database.
Technical description: Boiler has a fault for a specific error.
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 filling loop (braided flexible hose) underneath the boiler.Slowly open the one or two blue-handled valves until you hear water flowing.Close the valves tightly once the pressure gauge needle reaches between 1 and 1.5 bar.
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Gas Safe Register →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 27 April 2026