BoilerFaultCodesPotterton 8 (Flashing) Fault Code
Also written as 8FLASHING — same fault.
The Potterton 8 (Flashing) fault code means: your boiler has stopped working and locked itself out because it failed to light or stay lit correctly.. It appears on 2 Potterton models in our database.
Technical description: Boiler at lockout.
What causes the Potterton 8 (Flashing) fault?
This fault occurs when the boiler's control board fails to detect a stable flame after several attempts to ignite. The most common reasons are a worn-out ignition spark that can no longer light the gas or a dirty sensor that cannot 'see' the flame even if it is burning. In some cases, it may be caused by an inconsistent gas supply or a failing gas valve that isn't opening correctly.
DIY fix possible
Check if your gas supply is turned on (try another gas appliance like a hob).Press the reset button once to see if the boiler restarts.Ensure your condensate pipe has not frozen if it is a very cold day.
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Search the official register for a qualified engineer in your area.
Gas Safe Register →Potterton models that show the 8 (Flashing) fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Potterton 8 (Flashing) fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026