WATER OVERHEAT THERMOSTAT High

Ideal WATER OVERHEAT THERMOSTAT Fault Code

Also written as WATEROVERHEATTHERMOSTAT — same fault.

The Ideal WATER OVERHEAT THERMOSTAT fault code means: your boiler has switched itself off because it got too hot and needs a chance to cool down before it can restart safely.. It appears on 1 Ideal model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Safety device that triggers if water temperature exceeds limits
Typical repair cost £90-250 (including labour)

DIY fix possible

Check that all radiator valves are fully openAllow the boiler to cool down for at least 20 minutesPress the reset button on the front of the control panel

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Ideal models that show the WATER OVERHEAT THERMOSTAT fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ideal WATER OVERHEAT THERMOSTAT 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