High Lockout
LC6 on Ideal HP290

Your heat pump has stopped working because its internal computer board is having trouble communicating with or powering 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 main control system loses the ability to properly manage the compressor, which is the 'heart' of the machine. The most common reason is an electrical failure within the inverter circuit board or a breakdown in the wiring that provides power and instructions to the compressor.

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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Related fault codes

LC1View →LC3View →H6View →

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