BoilerFaultCodesPotterton E164 Fault Code
The Potterton E164 fault code means: your boiler is having trouble detecting when you turn on your hot water taps, which may result in your water staying cold.. It appears on 5 Potterton models in our database.
Technical description: DHW flow sensor fault
What causes the Potterton E164 fault?
This fault occurs when the boiler's internal computer can no longer detect the signal from the sensor that monitors water moving through the system. The most common reason is that the sensor has developed an electrical failure or the internal turbine has become stuck, meaning the boiler doesn't 'know' you have turned a tap on. In some cases, it can also be caused by loose or damaged wiring connecting the sensor to the main control board.
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 E164 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Potterton E164 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