Emergency
E83 485 on Potterton Promax 15 & 24

Your boiler has detected that it has become too hot and has automatically shut itself down to prevent any damage or safety hazards.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Overheat Thermostat

From this model's manual
Verified against the Potterton Promax 15 24 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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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