High
OVERHEAT THERMOSTAT on Halstead Ace High

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

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 appliance is fitted with an overheat thermostat. If the boiler overheats, the 'lockout' (red LED) will illuminate. This requires manual resetting of the thermostat button located behind the front casing.

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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