Medium
CP780 on Baxi 400 Combi 2

Your boiler's internal settings for managing different heating zones are currently confused or misconfigured.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Zone control strategy selection

From this model's manual
Verified against the Baxi 400 Combi 2 installation & service manual, page 53.
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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