High
Overheat thermostat lockout on Ideal Classic FF 330

Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent damage or danger.

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.

Technical description

The boiler is fitted with a safety 'cutout' thermostat. This thermostat will extinguish the pilot and shut down the boiler in the event of overheating.

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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