High Lockout
E131 on Baxi Duo-tec/Megaflo

Your boiler has shut down because it detected that the exhaust gases have become too hot, which is a safety feature to prevent damage to the internal components.

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 overheat lockout error

What causes this fault?

This fault occurs when the internal temperature sensors detect that the exhaust gases leaving your boiler have reached a dangerously high level. The most common reasons are a significant buildup of debris or limescale inside the heat exchanger, or damaged internal insulation panels that are no longer protecting the components from the burner's intense heat.

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

E110View →E130View →

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