High
E.04.18 on Baxi 400 Combi 2

Your boiler has stopped working because it cannot detect a high enough water temperature or it has lost its connection to one of the internal 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.

What the manual says

Manufacturer manual

Flow temperature below minimum or flow sensor not connected

From this model's manual
Verified against the Baxi 400 Combi 2 installation & service manual, page 72.
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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E.04.14View →E110View →E131View →

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