High
Red LED on Chaffoteaux 80/100

Your boiler has stopped working because it failed to start or got too hot, and it now needs to be manually restarted to begin operating 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.

Technical description

Ignition failure or overheat lock out (requires reset)

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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