High
Red LED (Overheat) on Potterton Kingfisher MF RSL

Your boiler has switched itself off because it became too hot, acting 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.

What the manual says

Manufacturer manual

The red LED will be illuminated if an overheat condition occurs. The overheat thermostat will require manual re-setting.

From this model's manual
Verified against the Potterton Boiler Kingfisher Mf Rs 40 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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