High
Safety thermostat activated on Potterton Performa 24

Your boiler has switched itself off because it got too hot, which is a built-in safety feature to prevent damage or dangerous overheating.

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

Press reset button on safety thermostat. If regular resetting is required, or appliance still does not operate, investigation is necessary. Check for continuity (more than 1.5 ohm).

From this model's manual
Verified against the Potterton Performa 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 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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