High Lockout
LC3 on Ideal HP290

Your heat pump has stopped working because of an internal electrical communication issue within its power control 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

Inverter Error

What causes this fault?

This fault occurs when the heat pump's internal computer loses the ability to communicate with the system that manages the power sent to the compressor. The most common reason is a failure of the inverter circuit board or a loose connection in the internal wiring, which prevents the unit from regulating its energy output.

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 →LC2View →P0View →

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