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.

What the manual says

Manufacturer manual

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.

From this model's manual
Verified against the Potterton Boilerkingfisher Mfrsl Cfl40 100 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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