Low
AM018 on Baxi 400 Combi 2

Your boiler is currently reading the temperature of the water returning to it, which is a normal part of its internal monitoring process rather than a breakdown.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Return temperature °C

From this model's manual
Verified against the Baxi 400 Combi 2 installation & service manual, page 56.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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