Emergency
Case temperature on Potterton Envoy 30

Your boiler has detected that it is becoming dangerously hot inside its outer shell and has switched itself off to prevent damage or fire risk.

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

Temperature within boiler casing too high See chart

From this model's manual
Verified against the Potterton Envoy 30 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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