BoilerFaultCodesIdeal Ed Fault Code
Also written as ED — same fault.
The Ideal Ed fault code means: your heat pump has stopped working because a sensor that monitors the temperature of the water returning to the outdoor unit has failed or detected an error.. It appears on 1 Ideal model in our database.
Technical description: Outdoor Unit, Return Thermistor (Tw_in) Error
What causes the Ideal Ed fault?
This fault occurs when the heat pump's control system loses a reliable signal from the sensor that measures water temperature coming back from your radiators. This is usually caused by a physical failure of the internal sensor probe or a loose connection in the wiring that carries the data. Without this information, the unit shuts down to prevent itself from overheating or running inefficiently.
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 Ed fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal Ed 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