High Lockout
J5E on Ideal HP290

Your heat pump’s main engine has encountered a problem and has stopped running to protect the system.

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

Compressor Error

What causes this fault?

This fault occurs when the heat pump's compressor, which is responsible for moving heat into your home, fails to start or shuts down unexpectedly. It is typically caused by a communication failure between the internal electronics or an electrical fault within the compressor unit itself. When this happens, the system stops running to prevent further electrical damage to the expensive internal components.

This fault is more frequent during extreme cold snaps when the compressor has to work at its maximum capacity for extended periods.

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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