BoilerFaultCodesRavenheat E04 Fault Code
The Ravenheat E04 fault code means: your boiler has detected a problem with the sensor that monitors hot water temperature, meaning you will likely have no hot water or inconsistent temperatures.. It appears on 9 Ravenheat models in our database.
Technical description: Domestic hot water (DHW) sensor damaged
What causes the Ravenheat E04 fault?
This fault occurs when the internal sensor responsible for measuring the temperature of your hot water fails or sends an incorrect signal to the boiler’s control board. The most common reason is that the sensor has either burnt out over time or developed a lime-scale build-up that prevents it from reading the water temperature accurately.
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 E04 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ravenheat E04 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