30 40 60 80 Medium

Chaffoteaux 30 40 60 80 Fault Code

Also written as 30406080 — same fault.

The Chaffoteaux 30 40 60 80 fault code means: your boiler has detected a faulty reading from the sensor that manages your hot water temperature.. It appears on 2 Chaffoteaux models in our database.

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.

Technical description: Thermistor sanitary bypassed.
Typical repair cost £120-200 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Chaffoteaux models that show the 30 40 60 80 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Chaffoteaux 30 40 60 80 fault code information on this page is sourced and cross-checked against the official Chaffoteaux service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026