High
Red LED (Overheat) on Potterton Kingfisher MF 40-100

Your boiler has become too hot and has automatically switched itself off to prevent damage, meaning you currently have no heating or hot water.

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 overheat thermostat has operated and will require manual re-setting. Repeated shutdown should be investigated.

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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