High
E 34 on Chaffoteaux Minima HE

Your boiler has identified a broken connection or faulty sensor in the vent system meant to carry waste gases away, so it has safely shut down to prevent unsafe operation.

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

Flue pipe sensor open circuit

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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Related fault codes

E 33View →E 35View →

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