BoilerFaultCodesIdeal E02 Fault Code
The Ideal E02 fault code means: your boiler has got too hot and has shut itself down as a safety precaution to prevent damage.. It appears on 6 Ideal models in our database.
Technical description: Safety thermostat (overheat)
What causes the Ideal E02 fault?
This fault occurs when the water inside the boiler exceeds a safe temperature, triggering a safety switch to cut power. The most common reasons are a pump failure preventing heat from moving away from the boiler, or a blockage such as 'sludge' in the pipework obstructing flow.
This fault often appears during the first few cold days of autumn when a heating system is turned back on after being idle all summer, which can cause the pump to seize.
DIY fix possible
Check that your radiator valves are open and not turned to offEnsure there is enough water pressure in the system (check the gauge reads between 1 and 1.5 bar)Press and hold the reset button for a few seconds to see if the boiler restarts
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Gas Safe Register →Ideal models that show the E02 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal E02 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