BoilerFaultCodesPotterton E128 Fault Code
The Potterton E128 fault code means: your boiler has lost its flame multiple times during operation and has safely shut down to prevent a malfunction.. It appears on 5 Potterton models in our database.
Technical description: Flame failure (12 times)
What causes the Potterton E128 fault?
This fault occurs when the boiler's internal sensors lose track of the flame too many times while the heating is running. It is usually caused by a worn-out component failing to detect the heat, or an inconsistent supply of gas and air preventing a steady flame from staying lit. The boiler eventually stops for safety because it cannot guarantee the fuel is burning correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Potterton models that show the E128 fault code
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Source
Potterton E128 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