BoilerFaultCodesPotterton E30 Fault Code
The Potterton E30 fault code means: your boiler has detected a problem with the sensor that monitors the temperature of the water leaving the unit, usually resulting in the system shutting down for safety.. It appears on 1 Potterton model in our database.
Technical description: Flow thermistor error
What causes the Potterton E30 fault?
This fault occurs when the control board loses communication with the sensor that monitors the temperature of the water as it leaves the boiler. The most common reason is that the sensor has physically failed or 'drifted' out of its correct electrical range, but it can also be caused by loose or damaged wiring. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution to prevent overheating.
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 E30 fault code
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Source
Potterton E30 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