High Lockout
L3E on Ideal HP290

Your heat pump's internal control board is experiencing an electrical communication problem and cannot operate the compressor.

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

Inverter Error

What causes this fault?

This fault occurs when the heat pump’s brain is unable to send signals to the motor that drives the heating process. It is usually caused by a physical failure of the internal electrical circuits or a loose connection that prevents the system from regulating the power needed to run. In some cases, it can be triggered by a sudden electrical surge or moisture getting into the control casing.

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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