BoilerFaultCodesChaffoteaux 08 Fault Code
The Chaffoteaux 08 fault code means: your boiler has stopped because the water pressure inside the system has dropped too low to operate safely.. It appears on 6 Chaffoteaux models in our database.
Technical description: No water in the primary circuit
DIY fix possible
Locate the filling loop (usually a silver braided hose with one or two valves underneath the boiler).Slowly open the valve(s) to allow mains water into the system until the pressure gauge on the front reads between 1.0 and 1.5 bar.Close the valve(s) tightly and restart the boiler.
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Gas Safe Register →Chaffoteaux models that show the 08 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Chaffoteaux 08 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