High
Overheat LED illuminated on Halstead Netaheat 10/16E

Your boiler has detected that it is running much hotter than it should be and has shut itself down as a safety precaution 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.

Technical description

Investigate the cause of the overheat situation and rectify. Possible causes: Lack of water; Lack of water flow; Faulty overheat thermostat; Faulty thermistor; Faulty aquastat

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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