High
0 (Flashing) on Potterton Envoy 30

Your boiler has stopped working because it failed to ignite or got too hot, and it now needs a manual reset to try and start again.

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

Boiler at Lock-Out. Indicates burner failing to light during a start sequence or a high temperature being recorded.

From this model's manual
Verified against the Potterton Boiler Envoy 60 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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