40 - 50 - 60 - 70 - 80 Low

Chaffoteaux 40 - 50 - 60 - 70 - 80 Fault Code

Also written as 4050607080 — same fault.

The Chaffoteaux 40 - 50 - 60 - 70 - 80 fault code means: your boiler has detected very cold temperatures and is running the pump and burner automatically to prevent the internal pipes from freezing.. It appears on 1 Chaffoteaux model in our database.

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.

Technical description: Antifrost mode on (burner and pump in operation).

DIY fix possible

Check that your electricity and gas supply are turned onEnsure your thermostat is set to a normal temperatureWait for the boiler to finish its warming cycle; the lights should stop flashing once it reaches a safe temperature

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Chaffoteaux models that show the 40 - 50 - 60 - 70 - 80 fault code

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

Source

Chaffoteaux 40 - 50 - 60 - 70 - 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