High
BOILER OVERHEAT THERMOSTAT on Ideal Classic RS

Your boiler has switched itself off completely because it has gotten too hot, which is a safety feature designed to prevent damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

This will interrupt the gas supply to the boiler and shut it down in the event of overheating

From this model's manual
Verified against the Ideal Classic Rs installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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