How much does it cost to fix Chaffoteaux error code 30-80 (L, M, M, L, M, M)?

Typical repair cost for the Chaffoteaux 30-80 (L, M, M, L, M, M) fault is £120-220 including labour.

30-80 (L, M, M, L, M, M) Medium

Chaffoteaux 30-80 (L, M, M, L, M, M) Fault Code

Q: What does the Chaffoteaux 30-80 (L, M, M, L, M, M) fault code mean?

Your boiler has lost the ability to detect the temperature of the water used for your taps and shower, so it has stopped providing hot water to ensure safety.

Also written as 3080LMMLMM — same fault.

The Chaffoteaux 30-80 (L, M, M, L, M, M) fault code means: your boiler has lost the ability to detect the temperature of the water used for your taps and shower, so it has stopped providing hot water to ensure safety.. It appears on 2 Chaffoteaux models in our database.

Technical description: Thermistor sanitary open

Typical repair cost £120-220 (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 30-80 (L, M, M, L, M, M) fault code

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

Source

Chaffoteaux 30-80 (L, M, M, L, M, M) 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