High Lockout
E01 on Ideal HP290

Your heat pump has stopped working because the internal safety system has detected a communication error or a power supply issue.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Fault code displayed on Heat Pump Controller/Control Box interface (technical description not provided in the snippet).

What causes this 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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