BoilerFaultCodesIdeal E6 Fault Code
The Ideal E6 fault code means: your heat pump's external temperature sensor is giving a faulty reading, which means the system cannot accurately adjust the heating based on the weather outside.. It appears on 1 Ideal model in our database.
Technical description: Outdoor Sensor within Outdoor Unit (T4) Error
What causes the Ideal E6 fault?
This fault occurs when the heat pump loses communication with the sensor that monitors the temperature of the air outside. The most common reason is that the sensor itself has developed an electrical fault or the wiring has become corroded or loose due to exposure to the elements. Without this data, the system cannot calculate how hard it needs to work to keep your home warm.
This issue is more frequent during autumn and winter when moisture and frost can accelerate corrosion in the sensor's electrical connections.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Ideal models that show the E6 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal E6 fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026