High
E.04 – .08 on Baxi Suprima 50

Your boiler has switched itself off because it has detected it is getting too hot or there is a problem with the internal safety sensors.

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

Permanent fault. Maximum safe temperature value reached, safety thermostat open-circuited, no circulation, sensor not or badly connected, bad connection or sensor fault.

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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