BoilerFaultCodesRavenheat 03E Fault Code
The Ravenheat 03E fault code means: the boiler's internal sensor that monitors water temperature or flow has failed, meaning the system cannot safely regulate heat.. It appears on 7 Ravenheat models in our database.
Technical description: Flow sensor damaged
What causes the Ravenheat 03E fault?
This fault occurs when the boiler's internal thermometer, which monitors the temperature of the water leaving the unit, stops sending a reliable signal to the main control board. The most common reason is that the sensor has physically failed due to age or heat stress, though it can also be caused by loose or corroded electrical connections between the sensor and the boiler's computer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Ravenheat models that show the 03E fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ravenheat 03E fault code information on this page is sourced and cross-checked against the official Ravenheat service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026