BoilerFaultCodesPotterton E385 Fault Code
The Potterton E385 fault code means: your boiler is not receiving enough electrical power from the mains supply to operate safely.. It appears on 2 Potterton models in our database.
Technical description: Under voltage
What causes the Potterton E385 fault?
This fault occurs when the electrical voltage being supplied to the boiler drops below the minimum level required for the internal components to function. Typically, this is caused by a problem with the mains electricity coming into the property or a loose connection within the boiler's internal wiring. In some cases, it can also be triggered by a failing printed circuit board that can no longer process the incoming power 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 E385 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Potterton E385 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