BoilerFaultCodesIdeal E01 Fault Code
The Ideal E01 fault code means: your heat pump has stopped working because the internal safety system has detected a communication error or a power supply issue.. It appears on 7 Ideal models in our database.
Technical description: Fault code displayed on Heat Pump Controller/Control Box interface (technical description not provided in the snippet).
What causes the Ideal E01 fault?
This fault occurs when the main control system loses its connection with the internal components, essentially meaning the different parts of the heat pump are no longer 'talking' to each other. The most common reason is a loose or damaged communication cable, or a failure in the circuit board that processes these signals. Without this constant flow of data, the system shuts down as a safety precaution.
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 E01 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal E01 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