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

Your boiler has detected that it is running too hot and has automatically shut itself down 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

It will require manual re-setting if an overheat condition occurs (the Red LED will be illuminated). The re-set button is located on the controls assembly.

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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